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دسترسی آزاد مقاله
1 - Photocatalytic degradation of Lidocaine HCl using CuO/ZnO nanoparticles
N. Badalpoor M. Giahi S. HabibiIn this paper, the photocatalytic degradation of Lidocaine HCl, an anesthetic was investigated inaqueous solution using CuO/ZnO as a photocatalyst. The degradation was studied under differentconditions including the amount of the photocatalyst, irradiation time, initial چکیده کاملIn this paper, the photocatalytic degradation of Lidocaine HCl, an anesthetic was investigated inaqueous solution using CuO/ZnO as a photocatalyst. The degradation was studied under differentconditions including the amount of the photocatalyst, irradiation time, initial concentration of drug,pH of the system, initial concentration, addition of oxidant on the reaction rate and anion presence.The results showed that the photocatalytic degradation of Lidocaine HCl was strongly influenced bythese parameters. The best conditions for the photocatalytic degradation of Lidocaine HCl wereobtained. The optimum amount of the photocatalyst used is 0.48 g/L. The photodegradationefficiency of Lidocaine HCl increases with the increase of the illumination time. It was found that thephotodegradation efficiency decreased with increasing the initial concentration of Lidocaine HCl.The photodegradation efficiency of Lidocaine HCl was accelerated by adding a small amount ofH2O2. The possible roles of the additives on the reactions and the possible mechanisms of effect werealso discussed. پرونده مقاله -
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2 - Photocatalytic degradation of methyl orange and Congo red using C,N,S-tridoped SnO2 nanoparticles
Azita Nouri Ali Fakhri Arezu NouriIn this study, the photocatalytic degradation of methyl orange and Congo red dye was investigated inaqueous solution using C,N,S-tridoped SnO2 nanoparticles as a nano photocatalyst. The degradationwas carried out under different conditions including the photocatalyst am چکیده کاملIn this study, the photocatalytic degradation of methyl orange and Congo red dye was investigated inaqueous solution using C,N,S-tridoped SnO2 nanoparticles as a nano photocatalyst. The degradationwas carried out under different conditions including the photocatalyst amount, initial concentrationand pH of the solution. The results indicated that the degradation of methyl orange and Congo redwas strongly influenced by these parameters. The best conditions for the degradation of methylorange and Congo red were obtained. The optimum value of photocatalyst amount used was 0.4 g/L.It was found that the photodegradation efficiency increase with increasing the initial concentration ofmethyl orange and Congo red. The optimum pH of the system used is 6.5. پرونده مقاله -
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3 - بررسی هم‌زمان فاکتورهای فرآیندی موثر در تخریب رنگ‌زای راکتیو آبی 19 از آب‌های آلوده با کمک نانو اکسیدهای فلزی (TiO2/Fe2O3) بر پایه کلینوپتیلولایت
آرسو اریمی مهرداد فرهادیان علیرضا سلیمانی‌نظر نیلا داوریزمینه و هدف: در این پژوهش با استفاده از زئولیت طبیعی و تثبیت هم زمان نانو ذرات اکسید آهن (III) و تیتانیم (IV) بر روی آن، نانوفتوکاتالیستی با قدرت تخریبی بیش تر، سنتز شد. عوامل مؤثر و نیز تداخلی در فرآیندی، تعیین شرایط بهینه عملیاتی بر بازده فرآیند تخریب رنگ زای راکتیو آ چکیده کاملزمینه و هدف: در این پژوهش با استفاده از زئولیت طبیعی و تثبیت هم زمان نانو ذرات اکسید آهن (III) و تیتانیم (IV) بر روی آن، نانوفتوکاتالیستی با قدرت تخریبی بیش تر، سنتز شد. عوامل مؤثر و نیز تداخلی در فرآیندی، تعیین شرایط بهینه عملیاتی بر بازده فرآیند تخریب رنگ زای راکتیو آبی 19 مورد بررسی قرار گرفت. روش بررسی: مشخصه یابی نانوفتوکاتالیست سنتز شده با آنالیزهای XRD، XRF، FT-IR، FE-SEM و EDX انجام گرفت. توانایی نانوفتوکاتالیست در تخریب رنگ زای راکتیو آبی 19 با کمک اشعه فرابنفش در طول‌موج 254 نانومتر و به روش طراحی آزمایش‌های تاگوچی مورد بررسی قرار گرفت و عوامل pH اولیه (7-2)، غلظت محلول رنگ زا (200-50 میلی‌گرم بر لیتر)، زمان پرتودهی (120-30 دقیقه) و غلظت نانوفتوکاتالیست (5/1-5/0 گرم بر لیتر) انتخاب شد. یافته‌ها: عوامل pH، غلظت محلول رنگ زا و زمان پرتودهی به ترتیب، بیش ترین اثر را بر بازده واکنش‌ها داشته‌اند.مقادیر بهینه عوامل در تخریب کامل آلاینده برابر با غلظت رنگ زا 50 میلی‌گرم بر لیتر، زمان پرتودهی 120 دقیقه، 2=pH و غلظت نانوفتوکاتالیست 5/1 گرم بر لیتر به دست آمد. بحث و نتیجه گیری: این پژوهش نشان داد که نانوفتوکاتالیست سنتزی بازده قابل قبولی در تخریب آلاینده زیست تخریب ناپذیر دارد. پرونده مقاله -
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4 - تعیین شرایط بهینه ی حذف متیل ارانژ از محلول های آبی توسط نانو ذره Ag, Co/TiO2 به روش طراحی آزمایش
نسیم ضیائی فر صابر خدایی آشان ژیلا طلعت مهر آباد فرزاد ارجمندی رادزمینه و هدف: در بررسی فعالیت فتو کاتالیزوری نانو ذره Ag, Co/TiO2 فاکتورهایی مانند مقدار غلظت آلاینده، مقدار فوتوکاتالیست،pH و دمای کلسیناسیون از عوامل موثر در فرایند حذف آلاینده در محلول های آبی است. با استفاده از طراحی آزمایش امکان حذف فاکتورهای غیر ضروری و تعیین شرایط چکیده کاملزمینه و هدف: در بررسی فعالیت فتو کاتالیزوری نانو ذره Ag, Co/TiO2 فاکتورهایی مانند مقدار غلظت آلاینده، مقدار فوتوکاتالیست،pH و دمای کلسیناسیون از عوامل موثر در فرایند حذف آلاینده در محلول های آبی است. با استفاده از طراحی آزمایش امکان حذف فاکتورهای غیر ضروری و تعیین شرایط بهینه صورت میگیرد. روش بررسی: نانو ذره Ag, Co/TiO2 سنتز شده جهت حذف متیل ارانژ استفاده گردید. و چهار متغیر مؤثر در فرآیند حذف متیل ارانژ، شامل غلظت اولیه ی آلاینده، مقدارفتو کاتالیست، pH و دمای کلسیناسیون به عنوان متغیرهای اصلی در نظر گرفته شد و آرایه ای با 4 فاکتور در 3 سطح در نظر گرفته شد. و جمعاً 9 آزمایش با در نظر گرفتن شرایط سطوح برای بهینه سازی و تعیین درجه ی تأثیر هریک از فاکتورها انجام گردید. یافته ها: تاثیر پارامترهای عملیاتی شامل غلظت اولیه ی آلاینده، مقدار فوتوکاتالیست، pH و دمای کلسیناسیون به عنوان متغیرهای اصلی به روش طراحی آزمایش بهینه‌سازی گردید. بحث و نتیجه گیری: نتایج آزمایشات بوسیله ی طراحی آزمایش, روش تاگوچی در تخریب فوتوشیمیایی متیل ارانژ نشان داد که مقدار غلظت متیل ارانژ و سپس مقدار کاتالیست بیش ترین تأثیر را در میان فاکتورهای انتخابی دارند. پرونده مقاله -
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5 - بررسی تخریب فتوکاتالیتیکی نفتالین توسط نانوکاتالیست های دی اکسید تیتانیوم داپ شده با N-S وP تحت نور مرئی
بهمن بنائی فرهنگ تیرگیر امیرحسام حسنی عبدالمجید فدایی سید مهدی برقعیزمینه و هدف: نفتالین یکی از هیدروکربن‌های آروماتیک چند حلقه‌ای سمی و خطرناک برای انسان و محیط زیست می باشد و حذف آن از محیط زیست ضروری است. هدف از این تحقیق بررسی تخریب فتوکاتالیتیکی نفتالین از محیط‌های آبی با استفاده از نانوکاتالیست‌های TiO2-P/SPA و TiO2-N,S/SiO2تحت نو چکیده کاملزمینه و هدف: نفتالین یکی از هیدروکربن‌های آروماتیک چند حلقه‌ای سمی و خطرناک برای انسان و محیط زیست می باشد و حذف آن از محیط زیست ضروری است. هدف از این تحقیق بررسی تخریب فتوکاتالیتیکی نفتالین از محیط‌های آبی با استفاده از نانوکاتالیست‌های TiO2-P/SPA و TiO2-N,S/SiO2تحت نور مرئی در حضور اکسیژن است. روش بررسی: این تحقیق در سال 1399 انجام گرفت. دو فتوکاتالیست TiO2-P/SPA و TiO2-N,S/SiO2به روش سل-ژل سنتز و از آنها برای حذف نفتالین از محیط آبی تحت نور مرئی در حضور اکسیژن، استفاده شد. اثر پارامترهای مختلف از جمله غلظت اولیه نفتالین،pH، مدت زمان تماس بررسی شدند و ساختار این نانو ذرات با استفاده از تصویر EDAX,SEM و آنالیز DRS بررسی گردید. یافته ها: تصاویر میکروسکوپ الکترونی اندازه ذرات فتوکاتالیست های سنتزی را 10 تا20 نانومتر نشان داد و ضخامت لایه نازک فتوکاتالیست TiO2-N,S/SiO2 و TiO2-P/SPA روی میکروگلوله‌ها به ترتیب برابر 68/698 نانومتر و 73/1 میکرومتر بود. آنالیزDRS نشان داد شکاف انرژی هر دو فتوکاتالیست باریک تر از TiO2 شده و فعالیت فتوکاتالیستی آنها به ناحیه نور مرئی انتقال یافته است. در شرایط بهینه حذف نفتالین مقادیر pH، زمان, غلظت نفتالین، و راندمان حذف به ترتیب برای فتوکاتالیست TiO2-N-S ، معادل 5، 50، 25، 23/94 و برای TiO2-P برابر 5، 40، 25، 39/97 به دست آمد (Pv<0.05). بحث و نتیجه گیری: این فتوکاتالیست ها می توانند به عنوان یک روش نوین، موثر و کاربردی در تصفیه آب و پساب‌های صنایع حاوی نفتالین، تحت نور خورشید و نور مریی استفاده شوند. پرونده مقاله -
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6 - Production of Nano TiO2 Coatedon Polypyrole Film for Degradation of Organic Dye
Razieh Razav Sayed Mohammad Ali HosseiniPolypyrol film was deposited on SS304by employing CPCvoltametery method, then coated with nano TiO2 (PPy/TiO2 )and used as a photocatalysis for degradation of somedyesacid fushin, methylenblue, methyl orange and methyl red. The SEM and XRD analysis indicated nano size o چکیده کاملPolypyrol film was deposited on SS304by employing CPCvoltametery method, then coated with nano TiO2 (PPy/TiO2 )and used as a photocatalysis for degradation of somedyesacid fushin, methylenblue, methyl orange and methyl red. The SEM and XRD analysis indicated nano size of TiO2 deposits as 20nm on the polypyrol film. The UV result of absorption revealed that this film increased the rate of degradation of dyes comparing with TiO2 powder. پرونده مقاله -
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7 - Synthesis, Characterization and Application of Zinc Oxide with Micro Polyhedral and Nano Plate Morphologies for Simultaneous Decolorization of Two- dye Mixture in Wastewater
Maryam MovahediIn this work, growth and assembly of the micro polyhedral zinc oxide was performed using airbubble assisted Triton X100, as a templating agent. In absence of air bubbling in the reactionsystem the nano plate zinc oxide was synthesized. The prepared samples were characte چکیده کاملIn this work, growth and assembly of the micro polyhedral zinc oxide was performed using airbubble assisted Triton X100, as a templating agent. In absence of air bubbling in the reactionsystem the nano plate zinc oxide was synthesized. The prepared samples were characterized by Xraydiffraction (XRD), field emission scanning electron microscopy (FE-SEM) and UV-Visspectrophotometer. The optical properties of the samples were evaluated by UV-Vis spectrum.Photocatalytic application of the samples for simultaneous decolorization of methylene blue (MB)and methyl orange (MO) dyes mixture in aqueous solution was examined. The Langmuir-Hinshelwood model for decolorization kinetic data was investigated. The reusability of the samplesafter five consecutive uses was examined. The photocatalytic results indicated that the micropolyhedral zinc oxide is a promising candidate for simultaneous decolorization of the MO and MBdyes (>90%). پرونده مقاله -
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8 - Preparation and Characterization of Nano ZnFe2O4 Supported on Copper Slag and its Effects on the Degradation of p-Xylene Aqueous Solution
Hossein Malekhosseini Morteza Khosravi Kazem Mahanpoor Fereshteh MotieeOne of the problems in removing pollutants from water by photocatalytic methodsistheseparationof thecatalystfrom thesolution. In this study, the catalyst stabilization method was used to solve this problem. Nano ZnFe2O4 supported on Copper Slag (CS) produced in this res چکیده کاملOne of the problems in removing pollutants from water by photocatalytic methodsistheseparationof thecatalystfrom thesolution. In this study, the catalyst stabilization method was used to solve this problem. Nano ZnFe2O4 supported on Copper Slag (CS) produced in this research is an environment-friendly, simple and cost-effective catalyst. ZnFe2O4 was prepared for co-precipitation methods and supported on CS by the thermal process. Its characterization was done by scanning electron microscopy (SEM) images, energy-dispersive X-ray spectroscopy (EDX), BET surface area and X-Ray diffraction patterns (XRD). The degradation of p-Xylene as a pollutant in water was performed by the UV + H2O2 process using ZnFe2O4/CS as a photocatalyst. Circulate Packed Bed Reactor (CPBR) was used. For photocatalytic degradation of the p-Xylene, full factorial experimental design with three factors containing pH, the initial concentration of p-Xylene and H2O2 in three levels was used. The best conditions were determined as pH= 9, the concentration of p-Xylene= 70 ppm and concentration of H2O2= 20 ppm. Degradation efficiency in the best condition was 95.40 %. This new catalyst can also be used in processes for organic pollutant degradation. پرونده مقاله -
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9 - Application of Semiconductor Photocatalysis for Effective Elimination of Organic Contaminants from Sewage
Soodabe GharibeThe ZnO/SiO2 semiconductor nanophotocatalysis was synthesized via sol-gel method. Also, theplatinum particles were loaded on the ZnO/SiO2 nanoparticles by photoreductive method. Thestructure of catalyst was confirmed by X-ray diffraction (XRD), scanning electron microsc چکیده کاملThe ZnO/SiO2 semiconductor nanophotocatalysis was synthesized via sol-gel method. Also, theplatinum particles were loaded on the ZnO/SiO2 nanoparticles by photoreductive method. Thestructure of catalyst was confirmed by X-ray diffraction (XRD), scanning electron microscopy(SEM) andfourier transform infrared spectroscopy (FT-IR). The XRD patterns of ZnO particlesdisplayed the nanoparticles have a wurtzite structure (hexagonal phase). The crystallite sizes werecalculated using Scheerer’s equation and were around 32nm. For photocatalytic test, decompositionof Malachite Green oxalate (MG), as an organic pollutant was carried out by synthesized catalyst. Acomparison of degradation between bare catalyst and platinum loaded ZnO/SiO2nanoparticle underUV-Vis light irradiation shows that the Pt-ZnO/SiO2 photocatalyst is more efficient than ZnO/SiO2nanoparticles. Also, the activity of ZnO/SiO2nanoparticles in the visible light are minimal, whileloading of Pt in zinc oxide network displaced the band gap toward longer wavelengths (visiblelight) and increased the photocatalysis activity of ZnO/SiO2 in the range of visible light. پرونده مقاله -
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10 - A Comparative Photocatalytic Activity of ZnO/SiO2 and V2O5-ZnO/SiO2 by Investigating the Degradation of Rhodamine B
Soodabe Gharibe Leila Vafayi Shahrara AfsharZnO/SiO2was prepared using sol-gel method, and vanadium particles were loaded on this nano-photocatalyst by wet incipient method. They characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive (EDX) analysis andFouriertransform i چکیده کاملZnO/SiO2was prepared using sol-gel method, and vanadium particles were loaded on this nano-photocatalyst by wet incipient method. They characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive (EDX) analysis andFouriertransform infrared spectroscopy (FT-IR). The XRD patterns showed that the zinc oxide samples have a wurtzite structure and vanadium doped is in V2O5crystalline structure. The particle sizes werearound 32 nmcalculated using Scherrer’s equation. For photocatalytic test, decomposition of Rhodamine B(RB), as an organic pollutant, was carried out. The photocatalyst V2O5- ZnO/SiO2was found to be more efficient as compared with ZnO/SiO2. پرونده مقاله -
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11 - Sonosynthesis and Characterization of TiO2/ZrO2 Nanocomposite and Photocatalytic degradation of Congo red Dye under UV Light
Khatere Jalili Shokufeh Aghabeygi Behroz MirzaNanoTiO2 , nanoZrO2 and TiO2 /ZrO2 nanocomposite were prepared via sol gel method by using ultrasonic irradiation. The precursor sol of zirconium was prepared from an aqueous solution of ZrCl4 and titanium tetra 2-propoxide was diluted by 2-propanol and deionized water چکیده کاملNanoTiO2 , nanoZrO2 and TiO2 /ZrO2 nanocomposite were prepared via sol gel method by using ultrasonic irradiation. The precursor sol of zirconium was prepared from an aqueous solution of ZrCl4 and titanium tetra 2-propoxide was diluted by 2-propanol and deionized water The TiO2 /ZrO2 nanocomposite was synthesized from directly mixing Titanium dried gel into Zirconium gel. The reaction mixture was placed under ultrasonic irradiation probe for 2 hours. The filtrated composite gel was washed and calcinated at 500 °C for 3h in furnace. The FT-IR spectroscopy and the XRD study were exhibited that the crystal structure and purity of the TiO2 /ZrO2 nano composite FESEM images were indicated the morphology and the average size of the NPs. The mean crystallite size of the NanoTiO2 , nanoZrO2 and TiO2 /ZrO2 nanocomposite were determined 57, 19 and 23 nm respectively. The photocatalytic performance was highly increased when nano-composite of TiO2 /ZrO2 was used to degradation of Congo red (CR) solution. The TiO2 /ZrO2 nano composite was shown higher photo-degradation efficiency than the pure nanoTiO2 and nanoZrO2 . پرونده مقاله -
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12 - Synthesis of Lead Titanate Nanostructure by Mechanical Activation Method and Evaluating of its Photocatalytic Decolorization of Methyl orange
E Khosravipanah S, A ManafiIn this study, lead titanate nanopowder was synthesized using mechanical activation. Raw materials including titanium oxide powder (anatase) and Lead oxide (ІІ) with a ball to powder weight ratio of 1: 10 and the powder ratio of 1:1 were milled in a planetary ball mill چکیده کاملIn this study, lead titanate nanopowder was synthesized using mechanical activation. Raw materials including titanium oxide powder (anatase) and Lead oxide (ІІ) with a ball to powder weight ratio of 1: 10 and the powder ratio of 1:1 were milled in a planetary ball mill for 30 hours. Then, they were heated at 800, 900 and 1000 °C. The volatility of lead and the formation of secondary phases were prevented using this method. The obtained nanopowder was investigated by field emission scanning electron microscope (FESEM), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR). The UV absorption spectroscopy was used to calculate the energy gap. Photocatalytic activity of nanopowder by dye degradation of methyl orange under UV light was evaluated. The effects of various influential parameters including initial dye concentration, photocatalyst dose and pH on the dye decolorization were also investigated. The optimum value for initial dye concentration and photocatalyst dose, obtained 10 ppm and 0.042 g, respectively. Also, the best rate of decolorization observed at pH=4. The results suggested that photocatalytic process is a beneficial method for decolorizing methyl orange dye. پرونده مقاله -
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13 - عملکرد نانوکامپوزیت GO- Fe3O4-ZnO به عنوان نانوفتوکاتالیزور برای حذف متیلن بلو و متیل اورانژ در حضور نور مرئی
حسن ملانژاد فرزانه ابراهیم زادهدر این مقاله، اکسید گرافن با اکسید آهن مغناطیسی ترکیب می‌شود و پس از افزوده شدن نانو ذرات اکسید روی، نانوکامپوزیت فتوکاتالیزوری مغناطیسی بر پایه اکسید گرافن حاصل می شود که به راحتی قابل جداسازی در حضور میدان مغناطیسی است. خواص نانوکامپوزیت توسط مطالعات مغناطیس سنج نمونه چکیده کاملدر این مقاله، اکسید گرافن با اکسید آهن مغناطیسی ترکیب می‌شود و پس از افزوده شدن نانو ذرات اکسید روی، نانوکامپوزیت فتوکاتالیزوری مغناطیسی بر پایه اکسید گرافن حاصل می شود که به راحتی قابل جداسازی در حضور میدان مغناطیسی است. خواص نانوکامپوزیت توسط مطالعات مغناطیس سنج نمونه ارتعاشی و میکروسکوپ الکترونی روبشی گسیل میدانی بررسی شد. از این نانوکامپوزیت به عنوان فتوکاتالیزور برای حذف آلودگی رنگی از جمله متیلن بلو و متیل اورانژ در حضور نور مرئی استفاده شد. نتایج مطالعات حذف آلودگی رنگ ها با طیف سنج مرئی نشان داد که حذف رنگ متیلن بلو به صورت کامل در زمان کوتاه و در مجاورت نور خورشید انجام می شود. از مزایای نانوکامپوزیت فوق می توان به سنتز بسیار ارزان، راحت و مقرون به صرفه بودن آن اشاره کرد. پرونده مقاله -
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14 - بررسی تصفیه پساب‌های حاوی آنتی‌بیوتیک توسط روش نانوفتوکاتالیزوری
عالیه محمدی شقایق لاله محمدرضا دوستیامروزه همگام با پیشرفت صنعت، آلودگی آب نیز رو به افزایش است. آلاینده ها از مسیرهای گوناگون به منابع زیرزمینی و روان آب های سطحی وارد می شوند و به عنوان تهدیدی بالقوه برای سلامت انسان و سایر جانداران در چرخه حیات قرار می گیرند. با اینکه تاکنون روش های مختلفی برای تصفیه چکیده کاملامروزه همگام با پیشرفت صنعت، آلودگی آب نیز رو به افزایش است. آلاینده ها از مسیرهای گوناگون به منابع زیرزمینی و روان آب های سطحی وارد می شوند و به عنوان تهدیدی بالقوه برای سلامت انسان و سایر جانداران در چرخه حیات قرار می گیرند. با اینکه تاکنون روش های مختلفی برای تصفیه آب و فاضلاب بکار رفته است اما اغلب این روش ها برای حذف بسیاری از آلاینده های آلی پایدار از جمله رنگ ها، داروها، حلال ها، آفت کش ها و غیره کارایی لازم را ندارند. آنتی بیوتیک ها از جمله آلاینده های آلی پایدار هستند که پس از مصرف به ندرت در بدن به طور کامل متابولیزه می شوند و 30 تا 90 درصد آن ها پس از دفع به صورت آلاینده های فعال در محیط زیست باقی می مانند. از این رو استفاده از روش های نوین نظیر فرایندهای فتوکاتالیزوری برای تصفیه آنتی بیوتیک ها مورد توجه پژوهشگران قرار گرفته است. با توجه به زمان کوتاه تولید نانوفتوکاتالیزور ها، قابلیت بازیافت و امکان استفاده مجدد از آن، تشکیل محصولات بی ضرر در طی واکنش، صرفه اقتصادی و سازگاری با محیط زیست، استفاده از نانو فتوکاتالیزور های نیمه هادی ناهمگن به عنوان یکی از فرایندهای اکسیداسیون پیشرفته، می تواند روشی موثر و کارآمد برای مقابله با آلودگی های زیست محیطی ناشی از آنتی بیوتیک ها باشد. در این مطالعه، ضمن معرفی روش اکسیداسیون پیشرفته، به نحوه به کارگیری نانو فتوکاتالیزور های ناهمگن، بررسی تأثیر عوامل عملیاتی مختلف واکنش فتوکاتالیزوری در تصفیه آب و فاضلاب حاوی آنتی بیوتیک ها و مطالعات مختلف و تحقیقات پبشین انجام شده در این زمینه پرداخته شده است. پرونده مقاله -
دسترسی آزاد مقاله
15 - سنتز نانوذرات اکسید نیکل با استفاده از عصاره گیاه کما و بررسی فعالیت فوتوکاتالیستی آن در تخریب بروموتیمول بلو
مونس هنرمند احمد آریافر مجید مهجورهدر این گزارش، برای اولین بار، سنتز نانوذرات اکسید نیکل (NiO) بواسطه عصاره گیاه کما انجام شد. برای ساخت نانوذرات اکسید نیکل از هیچ ماده احیاکننده شیمیایی، پایدار کننده سمی و حلال خطرناکی استفاده نشد و تمام مراحل ساخت در یک شرایط سبز و ملایم صورت پذیرفت. برای تعیین نوع فا چکیده کاملدر این گزارش، برای اولین بار، سنتز نانوذرات اکسید نیکل (NiO) بواسطه عصاره گیاه کما انجام شد. برای ساخت نانوذرات اکسید نیکل از هیچ ماده احیاکننده شیمیایی، پایدار کننده سمی و حلال خطرناکی استفاده نشد و تمام مراحل ساخت در یک شرایط سبز و ملایم صورت پذیرفت. برای تعیین نوع فاز و مورفولوژی نانوذرات اکسید نیکل بیوسنتز شده از آنالیز پراش اشعه ایکس (XRD) و میکروسکوپ الکترونی روبشی نشر میدانی (FE-SEM) استفاده شد. پس از بررسی نتایج شناسایی ها، به منظور برداشتن گامی جهت حفظ محیط زیست، نانوذرات اکسید نیکل بیوسنتز شده به عنوان فوتوکاتالیست موثر برای تخریب رنگ آلی بروموتیمول بلو مورد استفاده قرار گرفت. در این تحقیق، برای فعال کردن فوتوکاتالیست اکسید نیکل از لامپ UV استفاده شد. درصد تخریب رنگ بروموتیمول بلو در مدت زمان 3 ساعت به 08/77 رسید. برای ارزیابی امکان سنجی استفاده از نانوفوتوکاتالیست اکسید نیکل در صنعت، تخریب بروموتیمول بلو بر روی فاضلاب واقعی انجام و نتایج موفقیت آمیز حاصل شد. پرونده مقاله -
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16 - Hydrogen solar fuel generation from photocatalytic decomposition of H2S-containing media via nanostructured solid-solution semiconductor
M Ghanimati Sh Afshari M LashgariHydrogen sulfide is a flammable, malodorous, highly toxic and corrosive compound which is produced in large quantities as a by-product in many industrial processes. However, it will be economically and environmentally advantageous if it is photodecomposed to generate hy چکیده کاملHydrogen sulfide is a flammable, malodorous, highly toxic and corrosive compound which is produced in large quantities as a by-product in many industrial processes. However, it will be economically and environmentally advantageous if it is photodecomposed to generate hydrogen, which is a clean and renewable energy carrier. In this paper, a nanostructured solid-solution semiconductor material from the family of cadmium-zinc-sulfide was synthesized through a facile hydrothermal method and was applied as alloy photocatalyst to generate hydrogen fuel via a H2S photodecomposition process. Morphological and optical properties of the sample have been characterized by XRD, FE-SEM, EDS and UV-vis DRS techniques. Solid-solution semiconductor exhibited a good photocatalytic performance. پرونده مقاله -
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17 - A Review of Synthesis of an Efficient Photocatalyst for Photocatalytic Degradation of Organic Pollutants in Effluents
Paymaneh Taghizadeh-Lendeh Amir Hossein Mohsen Sarrafi Afshar Alihosseini Naeimeh Bahri-LalehIn recent years, with the increase in the growing speed of industries and population, water pollution and environmental pollution is a major challenge for the scientific community, which needs a serious and real solution in the world. Because the discharge of wastewater چکیده کاملIn recent years, with the increase in the growing speed of industries and population, water pollution and environmental pollution is a major challenge for the scientific community, which needs a serious and real solution in the world. Because the discharge of wastewater containing toxic substances, solid waste or flue gases from factories is known as a serious problem for the sustainable development of human society. Therefore, in this paper, which is a review of recent studies on this subject, first, an introduction to the catalytic degradation of pollutants is provided, and then the researcher's studies are reviewed, and finally, a conclusion is provided. In conclusion, it is found that in photocatalytic processes, the catalyst dosage is very effective on the rate of pollutant degradation. As the catalyst dosage increases, the number of active sites absorbing the pollutant at the catalyst surface also increases. The increasing trend of dye removal with catalyst dosage can be attributed to the increase in surface area and the availability of more absorption sites. This process continues until it increases light absorption and the production of hydroxyl radicals. However, it is also noteworthy that at values above the optimum, the reaction rate decreases. In other words, if the catalyst dosage is too high, not only it is not effective on the dye removal process, but also causes more turbidity of the solution, which in turn prevents the penetration of light and the effectiveness of the photocatalytic process. پرونده مقاله -
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18 - مطالعه سینتیکی حذف فوتوکاتالیستی رنگزا متیلن بلو با استفاده از ناتو ذرات نقره
پروین غربانی ارزو قادی امیر Amir علی مهری زادمتیلن بلو رایج ترین ماده رنگی جهت رنگ آمیزی پنبه، پشم و ابریشم است .استنشاق این ماده می تواند سبب اختلال در تنفس شده و حال آنکه مواجهه مستقیم با آن نیز می تواند سبب آسیب های دائمی چشم، احساس سوزش در نقاط در معرض تماس، تهوع و استفراغ، تعریق زیاد و اختلالات ذهنی گردد. در چکیده کاملمتیلن بلو رایج ترین ماده رنگی جهت رنگ آمیزی پنبه، پشم و ابریشم است .استنشاق این ماده می تواند سبب اختلال در تنفس شده و حال آنکه مواجهه مستقیم با آن نیز می تواند سبب آسیب های دائمی چشم، احساس سوزش در نقاط در معرض تماس، تهوع و استفراغ، تعریق زیاد و اختلالات ذهنی گردد. در این مقاله از یک روش ساده برای سنتز نقره استفاده شد. روش‌های شناسایی مختلفی مثل FESEM, TEM, FTIR, XRD, BET, UV-Vis DRS برای شناسایی مورفولوژی، ترکیب ساختاری و خواص نوری نانو نقره بکار رفت. نتایج UV-Vis DRS نشان داد که ساختار نانو نقره تهیه‌شده به‌طور مؤثری کارایی پاسخ نور مریی در فرایند تخریب فوتوکاتالیتیکی رنگ متیلن بلو را بهبود بخشید. نتایج سینتیک شبه مرتبه اول خطی نشان داد که مقدار k با افزایش غلظت رنگ از 0.0264 به0.0614 min-1 افزایش یافت.در کل، سنتز نانو نقره پتانسیل بالایی در حذف رنگ MB از محلول‌های آبی نشان داد. پرونده مقاله -
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19 - Photocatalytic removal of ceftriaxone from aqueous solutions using g-C3N4
Parvin GharbaniCeftriaxone is a one of Pharmaceutical compounds that cause pollution of water. In this research, g-C3N4 photocatalyst was synthesized and its efficiency in removal of ceftriaxone was studied. The synthesized g-C3N4 was analyzed using XRD, FTIR, FESEM,EDS and dot mappin چکیده کاملCeftriaxone is a one of Pharmaceutical compounds that cause pollution of water. In this research, g-C3N4 photocatalyst was synthesized and its efficiency in removal of ceftriaxone was studied. The synthesized g-C3N4 was analyzed using XRD, FTIR, FESEM,EDS and dot mapping. The effect of initial concentration of ceftriaxone, dosage of photocatalyst, irradiation time and pH was studied and based on these results, the highest removal efficiency of ceftriaxone from water was obtained about 83.4% at the concentration of 20 mg/L, pH=2 , 0.25 g/500 mL of g-C3N4 photocatalyst at 50 min of irradiation time. This study confirmed that g-C3N4 photocatalyst can be efficiently removed of ceftriaxone from water. پرونده مقاله -
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20 - Polyacrylamide synthesis of nanostructured copper aluminate for photocatalytic application
reza pournajaf Sayed Ali Hassanzadeh-TabriziThis paper reports the synthesis of nanostructured copper aluminate powders and their efficient application as a potential photocatalysts for photodegradation of organic dyes. The synthesized nanocomposites powders were characterized by XRD, TEM, DTA-TG analysis and UV- چکیده کاملThis paper reports the synthesis of nanostructured copper aluminate powders and their efficient application as a potential photocatalysts for photodegradation of organic dyes. The synthesized nanocomposites powders were characterized by XRD, TEM, DTA-TG analysis and UV-Vis spectroscopy. XRD results showed that pure and single phase copper aluminate was obtained after calcination at 700 °C. The obtained powders had a layered structure and each layer was composed of many nanoparticles which were inter connect to each other. The average particle size of samples calcined at 700 °C was about 26 nm. The photocatalytic activity of the prepared nanocatalysts was investigated via photodegradation of methyl orange under UV light. The band gap energy values of CuAl2O4 calcined at 700 and 900 °C are 1.79 and 1.72 eV, respectively. The results showed that the samples calcined at 700 °C showed the highest activity with 95 % photodegradation efficiency for degradation of methyl orange dye. پرونده مقاله -
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21 - Fabrication of Na-W Co-Doped Exfoliated G-C3N4 Nanoparticles for Methylene Blue Removal
Mohammad Javad Hakimi-Tehrani Seyed Ali Hassanzadeh Tabrizi Narjes Koupaei Ali Saffar Mahdi RafieiBulk g-C3N4 has very poor photocatalytic activity. Many methods have been utilized to increase the photocatalytic performance of this semiconductor. Here, a simple preparation was used to create exfoliated g-C3N4 that was co-doped with sodium and tungsten. The produced چکیده کاملBulk g-C3N4 has very poor photocatalytic activity. Many methods have been utilized to increase the photocatalytic performance of this semiconductor. Here, a simple preparation was used to create exfoliated g-C3N4 that was co-doped with sodium and tungsten. The produced Na-W co-doped exfoliated g-C3N4 was characterized using X-ray diffraction (XRD), transmission electron microscopy (TEM), UV-vis spectroscopy, and Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS). The doping samples with Na and W changed the band structure of the g-C3N4 lattice, which increased light absorption and caused a reduction in the band gap. The samples had layered morphology. After exfoliation and sodium and tungsten co-doping of the samples, the methylene blue photodegradation was greatly enhanced. The doping of the samples also had an impact on the dye adsorption capacity. The dye removal activity of the Na-W co-doped exfoliated g-C3N4 sample is higher than those of pure bulk g-C3N4 and pure exfoliated g-C3N4. The rate reaction constant (k) of the Na-W co-doped exfoliated g-C3N4 is up to 3.3 times greater than that of bulk g-C3N4. The produced photocatalyst may be utilized for the treatment of wastewater comprising methylene blue as the pollutant agent. پرونده مقاله -
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22 - MXene-based Nanostructures for Water Splitting Process Using the Density Functional Theory
Alireza Rastkar Ebrahimzadeh Sima Rastegar Jaber Jahanbin SardroodiSolar energy reserving and conversion into usable chemical energy with semiconductor photocatalysts help a promising method to solve both energy and environmental issues. Green and efficient energy technologies are crucial where nanoscience could change the paradigm shi چکیده کاملSolar energy reserving and conversion into usable chemical energy with semiconductor photocatalysts help a promising method to solve both energy and environmental issues. Green and efficient energy technologies are crucial where nanoscience could change the paradigm shift from fossil fuels to renewable sources. One of the most attractive cases is solar energy utilization to earn electricity or chemical fuel based on semiconductor nanomaterials ability to function as photocatalysts promoting various oxidation and reduction reactions under sunlight. Recently, two-dimensional (2D) materials have attracted particular focus because of their charming properties. We report on a novel class of two-dimensional photocatalysts for hydrogen generation via water splitting. In this paper, by Density Functional Theory (DFT) calculations, we investigated Hf2CO2 as two-dimensional transition metal carbides, referred to as MXene, to understand its photocatalytic properties. Using this method, we theoretically investigated the structural, electronic, and optical properties of MXene-based nanostructures such as Hf2CO2 that calculated using GGA-PBE and HSE06 functionals. The lattice constant for GGA-PBE functional for Hf2CO2 is 3.3592A°. The calculated band gaps for GGA-PBE and HSE06 functionals for two-dimensional Hf2CO2 MXene were 0.92 and 1.75 eV, respectively. This MXene-based nanostructure also exhibits excellent optical absorption performance. Hence, Hf2CO2 is a promising photocatalytic material. پرونده مقاله -
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23 - Response surface methodology analysis of the photocatalytic removal of Methylene Blue using a new Cu(II)-MOF
Zahra Mohseni nik Majid Ramezani Saeed Jamehbozorgi Tahere Momeni EsfahaniA novel metal–organic framework (MOF), with the formula [Cu(II)L]n (L= 4, 4′-diamino diphenyl sulfone), has been synthesized conventionally and hydrothermally methods and characterized by FT-IR, PXRD, EDX, and SEM techniques. The results MOFs were applied for photodegra چکیده کاملA novel metal–organic framework (MOF), with the formula [Cu(II)L]n (L= 4, 4′-diamino diphenyl sulfone), has been synthesized conventionally and hydrothermally methods and characterized by FT-IR, PXRD, EDX, and SEM techniques. The results MOFs were applied for photodegradation of Methylene Blue (MB). The influence of affecting variables, such as initial MB dye concentration (2–8mg L−1), Cu(II)-MOF mass (0.01–0.03 mg), pH (3.0–9.0), and time of irradiation (30–90 min). The photocatalytic degradation efficiency was investigated by the central composite design (CCD) methodology. The results of CCD analysis for optimum values of variables revealed that Cu(II)-MOF mass was 0.025g, the initial concentration of MB was 3.51 mg L−1, pH was 4.50 and irradiation time was 75 min.Under the optimum conditions, the photocatalytic MB degradation percentage at the desirability function value of 1.0 was found to be 70%. In addition, the obtained R2 value of 0.97 in the regression analysis showed a high photocatalytic efficiency of the proposed method for MB degradation. پرونده مقاله -
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24 - Employing α-Fe2O3 /Mn2P2O7 as a nano photocatalyst for degradation of toluene in aqueous environment
Sajjad Mafi Kazem MahanpoorThe existence of different resistant organic pollutants especially toxic organic aromatics such as Toluene in aquatic environments has become a significant environmental matter in recent years. In this paper, α-Fe2O3 Nano-spheres are immobilized on the surface of Mangan چکیده کاملThe existence of different resistant organic pollutants especially toxic organic aromatics such as Toluene in aquatic environments has become a significant environmental matter in recent years. In this paper, α-Fe2O3 Nano-spheres are immobilized on the surface of Manganese Pyrophosphate (Mn2P2O7) support using Forced Hydrolysis and Reflux Condensation (FHRC) method. Products were characterized by FTIR, SEM, BET EDX, and XRD. The photocatalytic activity of α-Fe2O3/Mn2P2O7 was investigated for the removal of Toluene in aqueous solution by UV/H2O2 system. The chemical oxygen demand (COD) measurements were used to determine the amount of Toluene removal. The experiments were designed based on four affecting variables including pH, catalyst content, initial Toluene concentration and H2O2 at three levels using Box-Behnken experimental design. The results of this study showed that α-Fe2O3/Mn2P2O7 as a new photo catalyst has a higher photocatalytic activity than α-Fe2O3 nanoparticles. Based on the achieved results, the maximum degradation efficiency was 97.14% in optimal conditions. پرونده مقاله -
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25 - Nanophotocatalytic Desulfurization of Hydrophane 10 Base Oil of Tehran Refinery
Reza FazaeliSulfur-containing compounds are one of the most important oil pollutants. Environmental pollutions, because of hazards on human health, corrosion in pipelines, and other refinery and installments necessitate sulfur removal. In this research, Ni(8%)/TiO2/Zeolite NaX nano چکیده کاملSulfur-containing compounds are one of the most important oil pollutants. Environmental pollutions, because of hazards on human health, corrosion in pipelines, and other refinery and installments necessitate sulfur removal. In this research, Ni(8%)/TiO2/Zeolite NaX nanophotocatalyst was synthesized and evaluated as a desulfurizer catalyst from hydrophane 10 base oil. Various tests including X-ray diffraction (XRD), Scanning Electron Microscopy (SEM), Energy-Dispersive X-ray Analysis (EDXA), Transmission Electron Microscopy (TEM), Atomic Force Microscopy (AFM), and BET/BJH were used to evaluate the photocatalyst synthesis process. Initially, using Design of Experiment (DOE) technique, optimum influential parameters were predicted, and 2D plus 3D diagrams were plotted. Then, 50 ml of oil containing 3782 ppm total sulfur, 0.6 g catalyst, 0.8 g adsorbent, and 3 h contact time were able to remove 20% of sulfur when exposed to the visible light. Sulfur was measured at all steps using inductively coupled plasma (ICP) technique. The final results suggested that the nanophotocatalytic process is a feasible way when compared to difficult and complicated steps with harder conditions. پرونده مقاله -
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26 - The removal of Hexavalent chromium; (Cr (VI)) by ZnO/LECA as a nano photocatalyst using full factorial experimental design
Aref Shokri Safoora KarimiIn this research, a synthesized nano photocatalyst was prepared by supporting ZnO nanoparticle on Lightweight expanded clay aggregate (LECA). The catalyst was synthesized by co-precipitation method. The SEM, FT-IR and XRD tests were used to characterize ZnO/LECA, which چکیده کاملIn this research, a synthesized nano photocatalyst was prepared by supporting ZnO nanoparticle on Lightweight expanded clay aggregate (LECA). The catalyst was synthesized by co-precipitation method. The SEM, FT-IR and XRD tests were used to characterize ZnO/LECA, which was employed for photocatalytic removal of Cr (VI) from aqueous solution in batch photoreactor. The full factorial experimental design (FFD) was used for the statistical analysis of data. The influence of catalyst amounts, pH, and initial concentration of Cr (VI) was investigated on the reduction of Cr (VI) to Cr (III). The number of active site was increased with increase in the concentration of catalyst to some extent. Also, the selection of other factors in optimized amount was important. The optimal conditions were obtained at 0.75 g/l of photocatalyst, pH at 5 and 20 mg/l of Cr(VI). The experimental and predicted reduction efficiency by FFD at optimal conditions were 97.6 and 96.18%, respectively. The comparison of experimental and predicted data showed a good agreement between them. پرونده مقاله -
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27 - The photo degradation of methyl red in aqueous solutions by α-Fe2O3/SiO2 nano photocatalyst
Majid Saghi Aref Shokri Ali Arastehnodeh Mohammad Khazaeinejad Atena NozariThe Photocatalytic degradation of chemical pollutants such as dyes, especially by Nano catalysts is an effective method to protect the environment and water resources. In this study, through Forced Hydrolysis and Reflux Condensation (FHRC) method the nanospherical α-Fe2 چکیده کاملThe Photocatalytic degradation of chemical pollutants such as dyes, especially by Nano catalysts is an effective method to protect the environment and water resources. In this study, through Forced Hydrolysis and Reflux Condensation (FHRC) method the nanospherical α-Fe2O3 particles were synthesized and supported on the surface of silica sand by Solid-State Dispersion (SSD) method with the average crystallite size of 27.5 nm. The characterization of catalyst and catalyst support was done using FTIR spectroscopy, SEM images, XRD patterns and BET surface area. In this paper, α-Fe2O3/SiO2 nanophotocatalyst was used for the removal of methyl red (MR) under ultraviolet (UV) light. After running different tests, the effective parameters such as the concentration of MR, pH, and mass of catalyst on pollutant degradation were optimized by single-variable method. The results showed that the optimum conditions for achieving 98.46 % of degradation were pH at 5, initial concentration of MR at 10 mg/l, and 2.0 g of α-Fe2O3/SiO2 nano photo catalyst. پرونده مقاله -
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28 - Modelling the degradation of Sunset Yellow FCF azo dye by Fe2O3/Bentonite catalyst using artificial neural networks
Reza Moradi Mohammad Ehsan Mosayebian Kazem MahanpoorIn this paper, the precipitation method has been used to stabilize Fe2O3 particles on Bentonite zeolite (BEN). Fe2O3/BEN catalysts have been characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD) and Brunauer-Emmett-Teller (BET) surface area analys چکیده کاملIn this paper, the precipitation method has been used to stabilize Fe2O3 particles on Bentonite zeolite (BEN). Fe2O3/BEN catalysts have been characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD) and Brunauer-Emmett-Teller (BET) surface area analysis. Artificial neural network (ANN) was used for modelling the photocatalytic degradation of Sunset Yellow FCF (SYF) azo dye in aqueous solution under irradiation in the batch photoreactor. The parameters including pH, catalyst amount, dye concentration and H2O2 concentration were applied as input; the output of the network was degradation percentage. Modelling the results the photocatalytic degradation of dye using a feed forward back propagation three-layer network, topology (4:7:1) with four neurons in the input layer, seven neurons in the hidden layer and one neuron in the output layer were used. Comparison between data obtained from ANN and experimental data indicated that the proposed ANN model provides reasonable predictive performance. The optimum conditions were as follow: pH= 4, catalyst amount=60 mg/L, dye concentration =50 ppm and H2O2 concentration =32 ppm. The chemical oxygen demand (COD) analysis of the dye under optimum conditions showed 91% reduction in 80 min period. پرونده مقاله -
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29 - Fabrication and photocatalytic degradation of reactive blue 19 by CuWO4, Ag3PO4 and CuWO4-Ag3PO4 composites under visible light irradiation
Mohammad javad Asadollahzadeh Aliakbar Arabameri Hamed Rashidi Javad seyfiCuWO4 nano-powder was synthesized via a hydrothermal reaction using CuCl2.2H2O and Na2WO4.2H2O in the stoichiometric 1:1 Cu:W molar ratio and sodium citrate as raw materials. Also, Ag3PO4 was synthesized by a precipitation method using Na2HPO4 and AgNO3. Finally, CuWO4- چکیده کاملCuWO4 nano-powder was synthesized via a hydrothermal reaction using CuCl2.2H2O and Na2WO4.2H2O in the stoichiometric 1:1 Cu:W molar ratio and sodium citrate as raw materials. Also, Ag3PO4 was synthesized by a precipitation method using Na2HPO4 and AgNO3. Finally, CuWO4-Ag3PO4 nanocomposite was synthesized in a precipitation route using the as-synthesized CuWO4 and Ag3PO4 as raw materials. The synthesized materials were characterized by the powder X-ray diffraction (PXRD) technique. In order to investigate the effect of concentration of the Basic solutions on the obtained materials morphology, the synthesized materials' morphologies were studied by field emission scanning electron microscopy (FESEM) technique. As shown by the FESEM images, the CuWO4 material morphology was spherical particles. Besides, the photocatalytic performance of the as-synthesized nanocomposites was studied for the degradation of Reactive Blue 19 (RB19) under direct visible light irradiation. For this purpose, several reaction parameters that affect the degradation yield, such as catalyst amount, pH value, and absence/presence of light, were investigated. The results indicate the higher photocatalytic yield at the presence of light irradiation when the solution's pH value was in the acidic range and the weight percent of silver phosphate in the composite mixture and the catalyst amount was more. The information revealed that a 0.05 g nanocomposite containing 0.24 mmole of Ag3PO4, with an initial pH of 3 and 100 mL of RB 19 with 30 mg/L concentration, approximately after 30 min, could remove completely under visible light illumination. پرونده مقاله -
دسترسی آزاد مقاله
30 - ZnO/WO3 nanocomposites: Pechini sol-gel synthesis, characterization, and photocatalytic performance for desulfurization of thiophene
Mehdi Mousavi-Kamazani Nahid Kalhori Mohammad GhodratiIn recent decades, considerable research about the destruction of hazardous pollutants sulfur from petroleum products was conducted. However, reforms in this area have not been satisfactory and efforts are ongoing. The aim of this study was to investigate and overcome t چکیده کاملIn recent decades, considerable research about the destruction of hazardous pollutants sulfur from petroleum products was conducted. However, reforms in this area have not been satisfactory and efforts are ongoing. The aim of this study was to investigate and overcome thiophene sulfur contaminants using high purity synthesized ZnO/WO3 nanocomposite and homogeneous composition by Pechini sol-gel method at low temperature. Zinc oxide is one of the most dynamic elements known in this field, its presence together with tungsten oxide prevents the crystallization of tungsten nanoparticles. Fuzzy structure, percentage of elements, surface morphology, penetration reflection spectrum, and photocatalytic degradation of thiophene were determined by XRD, EDS, SEM, and DRS analyzes, respectively. DRS results indicate high light absorption, reduced bandgap due to the presence of WO3 after combination with ZnO, and increased efficiency. Finally, the nanocomposite with more than 84% efficiency resulted in the degradation of oxidative desulfurization of thiophene after 150 min under visible light. پرونده مقاله -
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31 - Fabrication of Bi14W2O27/Bi2WO6 photocatalyst for improved desulfurization of thiophene under simulated sunlight irradiation
Mohammad Ebadi Majid Asri Farshad BeshkarIn this work, novel Bi14W2O27/Bi2WO6 nanocomposite was prepared by a modified Pechini sol-gel approach. The effect of the gelling agent, chelating agent and mole ratio of chelating agent to total metals was controlled to produce ultrafine Bi14W2O27/Bi2WO6 nanoparticles. چکیده کاملIn this work, novel Bi14W2O27/Bi2WO6 nanocomposite was prepared by a modified Pechini sol-gel approach. The effect of the gelling agent, chelating agent and mole ratio of chelating agent to total metals was controlled to produce ultrafine Bi14W2O27/Bi2WO6 nanoparticles. The as-prepared Bi14W2O27/Bi2WO6 nanocomposite was characterized by XRD, FESEM, FT-IR, EDS and UV–Vis analysis. The Bi14W2O27/Bi2WO6 nanostructures exhibited excellent photocatalytic desulfurization of thiophene (~90%) after 120 min of simulated sunlight irradiation. The high-efficiency photocatalytic desulfurization of the as-prepared Bi14W2O27/Bi2WO6 can be attributed to the improved visible-light absorption, ultrafine nanoparticles, and high separation and low recombination rates of charge carriers. In addition, a reliable photocatalytic desulfurization mechanism was explained using radical trapping experiment, which indicated that the photogenerated •O2− and •OH species had a significant contribution in the photocatalytic desulfurization reactions of Bi14W2O27/Bi2WO6 nanocomposite. The excellent photocatalytic desulfurization efficiency, good recyclability, solar-driven, and simple synthesis of Bi14W2O27/Bi2WO6 nanocomposite are promising for photocatalytic applications. پرونده مقاله -
دسترسی آزاد مقاله
32 - Application of TiO2/ZnS as a nano photocatalyst for degradation of Acid Red 18 in aqueous media using a central composite design
Aref Shokri Mahdi Sanavi FardIn this study, through the application of TiO2/ZnS as a novel nano photocatalyst, the degradation of AR18 in synthetic wastewater was explored. The nano photocatalyst was synthesized by the co-precipitation method and characterized by Scanning electron microscopy (SEM), چکیده کاملIn this study, through the application of TiO2/ZnS as a novel nano photocatalyst, the degradation of AR18 in synthetic wastewater was explored. The nano photocatalyst was synthesized by the co-precipitation method and characterized by Scanning electron microscopy (SEM), Fourier transfer infrared (FTIR), and X-ray powder diffraction (XRD) techniques. The average size of ZnS/TiO2 nano photocatalyst was 79nm. For experimental design and statistical analysis of each factor including AR18 concentration, pH, catalyst dosage, and treatment time on the degradation rate of AR18 (response) by Central Composite Design (CCD) was used. The analysis of variance (ANOVA) demonstrates a second-order regression model with R2 = 0.9995, adjusted R2=0.9991, and predicted R2=0.9982) for the removal of AR18. The optimum conditions for each operating factor were as the following: AR18 concentration at 30 mg.L-1, catalyst dosage at 1.2 g.L-1, pH at 5, and treatment time at 120 min. In this condition, the actual and predicted AR18 removal was 94% and, 93.07%, respectively. پرونده مقاله -
دسترسی آزاد مقاله
33 - Preparation of Ag Loaded WO3 Nano Rod and Its Highly Efficient Degradation of Flumequine under Sunlight Irradiation
Somayeh Saleh Fekr Mehdi Ardjmand Reza Fazaeli Mehdi RafizadehThe aim of this study was to evaluate the efficiency of Ag/WO3 photocatalytic process for degradation of Flumequine (FL) antibiotic from aqueous solutions. In this study, WO3 and Ag/WO3 particles were synthesized and characterized using X-ray diffraction (XRD), Fourier- چکیده کاملThe aim of this study was to evaluate the efficiency of Ag/WO3 photocatalytic process for degradation of Flumequine (FL) antibiotic from aqueous solutions. In this study, WO3 and Ag/WO3 particles were synthesized and characterized using X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), scanning electron microscope (SEM), energy dispersive X-ray spectrometry (EDS)/Map, Brunauer, Emmett, Teller (BET)/Barrett, Joyner, Halenda (BJH) and UV–vis diffuse reflectance spectroscopy (DRS) techniques. The photocatalytic degradation of FL from aqueous solutions was studied by Ag/WO3 photocatalyst under sunlight irradiation. The response surface methodology (RSM) with Central Composite Design (CCD) with 4 variables was used to investigate the relationship between the obtained responses and process variables and optimize with Design Expert software. In this study, the effect of pH, time (min), photocatalyst mass (g) and FL concentration (mg/L) were evaluated at 5 levels. Finally, the software is the best point to achieve the highest degradation efficiency of FL 99.54%, in optimal conditions at pH 3.07, time 101.14 (min), photocatalyst mass 0.13 (g) and FL concentration 41.3 (mg/L). پرونده مقاله -
دسترسی آزاد مقاله
34 - Pechini Sol-Gel Synthesis and Characterization of NiWO4/W5O14/WO3 Nanocomposite for Photocatalytic Desulfurization of Thiophene
Mehdi Mousavi-Kamazani Mahvash Siahmansouri Mohammad GhodratiOne of the most important problems in the oil industry is the presence of sulfur and sulfur compounds in crude oil. Sulfur compounds in crude oil can have detrimental effects on the environment, equipment, catalysts, and end products. One of the most important goals of چکیده کاملOne of the most important problems in the oil industry is the presence of sulfur and sulfur compounds in crude oil. Sulfur compounds in crude oil can have detrimental effects on the environment, equipment, catalysts, and end products. One of the most important goals of researchers in recent years is to sweeten petroleum products from these compounds. This study aims to use NiWO4/W5O14/WO3 composite nanostructure to solve this problem using the photocatalytic oxidative desulfurization method. This composite nanostructure has been synthesized by Pechini sol-gel method with high purity at low temperature and examined by XRD, EDS, FESEM, and FT-IR analysis. Due to the presence of WO3 in the composition, the bandgap was greatly reduced and the efficiency was increased. As a result, the nanostructure could degrade more than 73% of the sulfur in thiophene in 180 min under visible light. By optimizing the amount of photocatalyst and irradiation time, the efficiency can be improved. پرونده مقاله -
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35 - Degradation of Chloridazon in an aqueous environment using TiO2/Ag as a synthesized nano photocatalyst using central composite design
Maysam Abdolkarimi Fariba Soleimani Aref ShokriIn this study, TiO2/Ag nano photocatalyst was synthesized by sol-gel method and used for degradation of Chloridazon (CLZ) in aqueous media. The prepared catalyst was characterized using powder X-ray diffractometry (XRD), Fourier transform infra-red (FTIR), and field emi چکیده کاملIn this study, TiO2/Ag nano photocatalyst was synthesized by sol-gel method and used for degradation of Chloridazon (CLZ) in aqueous media. The prepared catalyst was characterized using powder X-ray diffractometry (XRD), Fourier transform infra-red (FTIR), and field emission scanning electron microscopy (FESEM) techniques. The Crystallite size of pure TiO2 and Ag/TiO2 nanoparticles was 20 and 60 nm, respectively. The Central Composite Design (CCD) was employed for experimental design and statistical analysis of independent operational parameters. According to the results of Response Surface Methodology (RSM) plots of Design-Expert software, the optimal conditions for each critical variable were as the follows: time at 113 min, pH at 6.8, initial concentration of CLZ at 40 mg/l, and catalyst concentration at 0.83gr/l. The maximum effectiveness in the experimental and predicted CLZ removal was 94.2 and 93.5%, respectively. The outcomes of Analysis of variance (ANOVA) demonstrated high determination coefficient quantities (R2 = 0.9997, Predicted R2=0.9989, and Adjusted R2=0.9994) which validated the reliability of the second-order regression model. پرونده مقاله -
دسترسی آزاد مقاله
36 - Nanophotocatalytic Desulfurization of Hydrophane 10 Base Oil of Tehran Refinery
Mojgan Jalali Farahani Reza Fazaeli Ensieh GhasemiIn this research, Ni(8%)/TiO2/Zeolite NaX nanophotocatalyst was synthesized andevaluated as a desulfurizer catalyst from hydrophane 10 base oil. Various tests,including X-ray diffraction (XRD), Scanning Electron Microscopy (SEM), Energy-Dispersive X-ray Analysis (EDXA), چکیده کاملIn this research, Ni(8%)/TiO2/Zeolite NaX nanophotocatalyst was synthesized andevaluated as a desulfurizer catalyst from hydrophane 10 base oil. Various tests,including X-ray diffraction (XRD), Scanning Electron Microscopy (SEM), Energy-Dispersive X-ray Analysis (EDXA), Transmission Electron Microscopy (TEM), AtomicForce Microscopy (AFM), and BET/BJH were used to evaluate the photocatalystsynthesis process. Initially, using Design of Experiment (DOE) technique, optimuminfluential parameters were predicted, and 2D plus 3D diagrams were plotted.Then, 50 ml of oil containing 3782 ppm total sulfur, 0.6 g catalyst, 0.8 g adsorbent,and 3 h contact time were able to remove 20% of sulfur when exposed to thevisible light. Sulfur was measured at all steps using inductively coupled plasma(ICP) technique. The final results suggested that the nanophotocatalytic processis a feasible way when compared to difficult and complicated steps with harderconditions. پرونده مقاله -
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37 - Exfoliated graphite/Selenium-Zinc Oxide Nanocomposites for Photodegradation of Organic Dye in Water and Its Antibacterial Activity Against Aater Borne Pathogens
Olubori Idowu Sonde Moses Gbenga Peleyeju Fatai Oladipupo Oladoyinbo Adejare Rasaq Oloyede Tajudeen Adeniyi Afolabi Hameed Adekola Adesokan Omotayo Ademola Arotiba Enoch Olugbenga DareWe report the synthesis and application of a novel Exfoliated graphite/Selenium-Zinc oxide (EG/Se-ZnO) nanocomposite for photodegradation of methylene blue dye and its antibacterial activity. The composite was characterized using XRD, FTIR, SEM and TEM. Applicability of چکیده کاملWe report the synthesis and application of a novel Exfoliated graphite/Selenium-Zinc oxide (EG/Se-ZnO) nanocomposite for photodegradation of methylene blue dye and its antibacterial activity. The composite was characterized using XRD, FTIR, SEM and TEM. Applicability of EG/ Se-ZnO nanocomposite as photocatalyst was investigated by the photocatalytic degradation of methylene blue as a model for organic pollutant. The XRD has its highest peak at 101 which indicated that ion diffusion was free from solvent viscosity (peak at 002). FTIR spectra confirmed the formation of EG/Se-ZnO nanocomposite as band at 882 cm-1 and 612 cm-1, 727 cm-1, 1373 cm-1 were associated with vibrational frequency of ZnO lattice and Selenium respectively. The SEM revealed cloudy large particles of the synthesized EG/Se-ZnO composite. TEM image revealed mini-rodlike nanoparticles. 99.5% degradation of methylene blue dye was achieved within 90 minutes of irradiation. The reactions followed first order kinetics with the rate constant of 5.79x10 -2 min-1 and R2 value of 0.9. The enhanced photocatalytic activity of EG/Se-ZnO was ascribed to the capability of graphitic layers to accept and transport electrons from the excited ZnO promoting charge separation. The antibacterial activity was also evaluated for the ZnO (bulk) and EG/Se-ZnO nanocomposite against the control (ciprofloxacin) and zone of inhibition observed was on E. coli and E.cloacae respectively depicted that EG/Se-ZnO was more effective on E. coli relatively to bulk ZnO. Thus, EG/Se-ZnO nanocomposite can be used for photocatalytic organic pollutant degradation. پرونده مقاله -
دسترسی آزاد مقاله
38 - Photodegradation of methylene blue in aqueous solution by a new Cu(II)-MOF based on diamino diphenyl sulfone ligand through response surface methodology (RSM)
Zahra Moseni nik Saeed Jamehbozorgi Majid Ramezani Tahere Momeni EsfahaniA novel metal-organic framework (MOF), with the formula [Cu(II)L]n (L= 4, 4′-diamino diphenyl sulfone), has been synthesized conventionally and hydrothermally methods and characterized by FT-IR, PXRD, EDX, and SEM techniques. The results MOFs were applied for phot چکیده کاملA novel metal-organic framework (MOF), with the formula [Cu(II)L]n (L= 4, 4′-diamino diphenyl sulfone), has been synthesized conventionally and hydrothermally methods and characterized by FT-IR, PXRD, EDX, and SEM techniques. The results MOFs were applied for photodegradation of MethyleneBlue (MB). The influence of affecting variables, such as initial MB dye concentration (2–8mg L−1), Cu(II)-MOF mass (0.01–0.03 mg), pH (3.0–9.0), and time of irradiation (30–90 min). The photocatalytic degradation efficiency was investigated by the central composite design (CCD) methodology. The results of CCD analysis for optimum values of variables revealed that Cu(II)-MOF mass was 0.025g, theinitial concentration of MB was 3.51 mg L−1, pH was 4.50, and irradiation time was 75 min. Under the optimum conditions, the photocatalytic MB degradation percentage at the desirability function value of 1.0 was found to be 70%. In addition, the obtained R2 value of 0.97 in the regression analysis showed a high photocatalytic efficiency of the proposed method for MB degradation. پرونده مقاله -
دسترسی آزاد مقاله
39 - Photo Degradation of methylene blue in aqueous solution by a new Cu(II)-MOF based on diaminodiphenyl sulfone ligand through response surface methodology (RSM)
Zahra Moseni nik Saeed Jamehbozorgi Majid Ramezani Tahere Momeni EsfahaniA novel metal–organic framework (MOF), with the formula [Cu(II)L]n (L=4, 4′-diamino diphenyl sulfone), has been synthesized conventionally andhydrothermally methods and characterized by FT-IR, PXRD, EDX, and SEMtechniques. The results MOFs were applied for p چکیده کاملA novel metal–organic framework (MOF), with the formula [Cu(II)L]n (L=4, 4′-diamino diphenyl sulfone), has been synthesized conventionally andhydrothermally methods and characterized by FT-IR, PXRD, EDX, and SEMtechniques. The results MOFs were applied for photodegradation of MethyleneBlue (MB). The influence of affecting variables, such as initial MB dyeconcentration (2–8mg L−1), Cu(II)-MOF mass (0.01–0.03 mg), pH (3.0–9.0), andtime of irradiation (30–90 min). The photocatalytic degradation efficiency wasinvestigated by the central composite design (CCD) methodology. The resultsof CCD analysis for optimum values of variables revealed that Cu(II)-MOF masswas 0.025g, the initial concentration of MB was 3.51 mg L−1, pH was 4.50 andirradiation time was 75 min.Under the optimum conditions, the photocatalytic MBdegradation percentage at the desirability function value of 1.0 was found to be70%. In addition, the obtained R2 value of 0.97 in the regression analysis showeda high photocatalytic efficiency of the proposed method for MB degradation. پرونده مقاله -
دسترسی آزاد مقاله
40 - Fabrication and photocatalytic degradation of reactive blue 19 by CuWO4, Ag3PO4, and CuWO4-Ag3PO4 composites under visible light irradiation
Aliakbar Arabameri Mohammad javad Asadollahzadeh Hamed Rashidi Javad SeyfiCuWO4 nano-powder was synthesized via a hydrothermal reaction using CuCl2.2H2Oand Na2WO4.2H2O in the stoichiometric 1:1 Cu:W molar ratio and sodiumcitrate as raw materials. In addition, Ag3PO4 was synthesized by a precipitationmethod using Na2HPO4 and AgNO3. Finally, Cu چکیده کاملCuWO4 nano-powder was synthesized via a hydrothermal reaction using CuCl2.2H2Oand Na2WO4.2H2O in the stoichiometric 1:1 Cu:W molar ratio and sodiumcitrate as raw materials. In addition, Ag3PO4 was synthesized by a precipitationmethod using Na2HPO4 and AgNO3. Finally, CuWO4-Ag3PO4 nanocomposite wassynthesized in a precipitation route using the as-synthesized CuWO4 and Ag3PO4as raw materials. The synthesized materials were characterized by powder X-raydiffraction (PXRD) technique. To investigate the effect of concentration of the basicsolutions on the morphology of the obtained materials, the morphologies of thesynthesized materials were studied by field emission scanning electron microscopy(FESEM) technique. As shown by the FESEM images, the morphology of CuWO4the material was spherical particles. Besides, the photocatalytic performance of theas-synthesized nanocomposites was studied for the degradation of ReactiveBlue 19 (RB19) under directly visible light irradiation. For this purpose, severalreaction parameters affect the degradation yield, such as catalyst amount, pHvalue and absence/presence of light were investigated. The data showed thatthe photocatalytic yield at the presence of light irradiation was more when theThe pH value of the solution was in the acidic range, the weight percent of silverphosphate in the composite mixture was more, and the catalyst amount wasmore. The findings revealed that a 0.05 g nanocomposite containing 0.24 mmoleof Ag3PO4, with an initial pH of 3 and RB 19 volume and concentration of 100 mLand 30 mg/L, respectively, could achieve approximately complete removal after30 min under visible light illumination. پرونده مقاله -
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41 - The photo degradation of methyl red in aqueous solutions by α-Fe2O3/SiO2 nano photocatalyst
Majid Saghi Aref Shokri Ali Arastehnodeh Mohammad Khazaeinejad Atena NozariThe Photocatalytic degradation of chemical pollutants such as dyes, especially by Nano catalysts is an effective method to protect the environment and water resources. In this study, through Forced Hydrolysis and Reflux Condensation (FHRC) method the nanospherical &alph چکیده کاملThe Photocatalytic degradation of chemical pollutants such as dyes, especially by Nano catalysts is an effective method to protect the environment and water resources. In this study, through Forced Hydrolysis and Reflux Condensation (FHRC) method the nanospherical α-Fe2O3 particles were synthesized and supported on the surface of silica sand by Solid-State Dispersion (SSD) method with the average crystallite size of 27.5 nm. The characterization of catalyst and catalyst support was done using FTIR spectroscopy, SEM images, XRD patterns and BET surface area.In this paper, α-Fe2O3/SiO2 nano photocatalyst was used for the removal of methyl red (MR) under ultraviolet (UV) light. After running different tests, the effective parameters such as the concentration of MR, pH, and mass of catalyst on pollutant degradation were optimized by single-variable method. The results showed that the optimum conditions for achieving 98.46 % of degradation were pH at 5, initial concentration of MR at 10 mg/l, and 2.0 g of α-Fe2O3/SiO2 nano photo catalyst. پرونده مقاله -
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42 - The removal of Hexavalent chromium; (Cr (VI)) by ZnO/LECA as a nano photocatalyst using full factorial experimental design
Safoora Karimi Aref ShokriIn this research, a synthesized nano photocatalyst was prepared by supportingZnO nanoparticle on Lightweight expanded clay aggregate (LECA). The catalystwas synthesized by the co-precipitation method. The SEM, FT-IR, and XRD testswere used to characterize ZnO/LECA, whic چکیده کاملIn this research, a synthesized nano photocatalyst was prepared by supportingZnO nanoparticle on Lightweight expanded clay aggregate (LECA). The catalystwas synthesized by the co-precipitation method. The SEM, FT-IR, and XRD testswere used to characterize ZnO/LECA, which was employed for photocatalyticremoval of Cr (VI) from an aqueous solution in a batch photoreactor. The fullfactorial experimental design (FFD) was used for the statistical analysis of data.The influence of catalyst amounts, pH, and initial concentration of Cr (VI) wasinvestigated on the reduction of Cr (VI) to Cr (III). The number of active sites wasincreased with an increase in the concentration of catalyst to some extent. Also,the selection of other factors in the optimized amount was important. The optimalconditions were obtained at 0.75 g/l of photocatalyst, pH at 5 and 20 mg/l ofCr(VI). The experimental and predicted reduction efficiency by FFD at optimalconditions were 97.6 and 96.18%, respectively. The comparison of experimentaland predicted data showed a good agreement between them. پرونده مقاله -
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43 - Modeling the degradation of Sunset Yellow FCF azo dye by Fe2O3/Bentonite catalyst using artificial neural networks
Mohammad Ehsan Mosayebian Reza Moradi Kazem MahanpoorIn this paper, the precipitation method has been used to stabilize Fe2O3 particleson Bentonite zeolite (BEN). Fe2O3/BEN catalysts have been characterized byscanning electron microscopy (SEM), X-ray diffraction (XRD), and Brunauer-Emmett-Teller (BET) surface area analysi چکیده کاملIn this paper, the precipitation method has been used to stabilize Fe2O3 particleson Bentonite zeolite (BEN). Fe2O3/BEN catalysts have been characterized byscanning electron microscopy (SEM), X-ray diffraction (XRD), and Brunauer-Emmett-Teller (BET) surface area analysis. Artificial neural network (ANN)was used for modeling the photocatalytic degradation of Sunset Yellow FCF(SYF) azo dye in aqueous solution under irradiation in the batch photoreactor.The parameters including pH, catalyst amount, dye concentration and H2O2concentration was applied as input; the output of the network was degradationpercentage. Modeling the results of the photocatalytic degradation of dye using afeed-forward, backpropagation three-layer network, topology (4:7:1) with fourneurons in the input layer, seven neurons in the hidden layer, and one neuron inthe output layer was used. Comparison between data obtained from ANN andexperimental data indicated that the proposed ANN model provides reasonablepredictive performance. The optimum conditions were as follows: pH= 4, catalystamount=60 mg/L, dye concentration =50 ppm and H2O2 concentration =32ppm. The chemical oxygen demand (COD) analysis of the dye under optimumconditions showed a 91% reduction in 80 min period. پرونده مقاله -
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44 - Fabrication and photocatalytic degradation of reactive blue 19 by CuWO4, Ag3PO4, and CuWO4-Ag3PO4 composites under visible light irradiation
Aliakbar Arabameri Mohammad Javad Asadollahzadeh Hamed Rashidi Javad SeyfiCuWO4 nano-powder was synthesized via a hydrothermal reaction usingCuCl2.2H2O and Na2WO4.2H2O in the stoichiometric 1:1 Cu:W molar ratio andsodium citrate as raw materials. Also, Ag3PO4 was synthesized by a precipitationmethod using Na2HPO4 and AgNO3. Finally, CuWO4-Ag3 چکیده کاملCuWO4 nano-powder was synthesized via a hydrothermal reaction usingCuCl2.2H2O and Na2WO4.2H2O in the stoichiometric 1:1 Cu:W molar ratio andsodium citrate as raw materials. Also, Ag3PO4 was synthesized by a precipitationmethod using Na2HPO4 and AgNO3. Finally, CuWO4-Ag3PO4 nanocompositewas synthesized in a precipitation route using the as-synthesized CuWO4 andAg3PO4 as raw materials. The synthesized materials were characterized by thepowder X-ray diffraction (PXRD) technique. In order to investigate the effect ofconcentration of the Basic solutions on the obtained materials,morphology, thesynthesized materials’ morphologies were studied by field emission scanningelectron microscopy (FESEM) technique. As shown by the FESEM images, theCuWO4 material morphology was spherical particles. Besides, the photocatalyticperformance of the as-synthesized nanocomposites was studied for thedegradation of Reactive Blue 19 (RB19) under direct visible light irradiation. Forthis purpose, several reaction parameters that affect the degradation yield, suchas catalyst amount, pH value, and absence/presence of light, were investigated.The results indicate the higher photocatalytic yield at the presence of lightirradiation when the solution’s pH value was in the acidic range and the weightpercent of silver phosphate in the composite mixture and the catalyst amountwas more. The information revealed that a 0.05 g nanocomposite containing0.24 mmole of Ag3PO4, with an initial pH of 3 and 100 mL of RB 19 with 30 mg/Lconcentration, approximately after 30 min, could remove completely undervisible light illumination. پرونده مقاله -
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45 - MXene-based Nanostructures for Water Splitting Process Using the Density Functional Theory
Sima Rastegar Alireza Rastkar Ebrahimzadeh Jaber Jahanbin SardroodiSolar energy reserving and conversion into usable chemical energy withsemiconductor photocatalysts help a promising method to solve both energy andenvironmental issues. Green and efficient energy technologies are crucial wherenanoscience could change the paradigm shift چکیده کاملSolar energy reserving and conversion into usable chemical energy withsemiconductor photocatalysts help a promising method to solve both energy andenvironmental issues. Green and efficient energy technologies are crucial wherenanoscience could change the paradigm shift from fossil fuels to renewablesources. One of the most attractive cases is solar energy utilization to earnelectricity or chemical fuel based on semiconductor nanomaterials' ability tofunction as photocatalysts promoting various oxidation and reduction reactionsunder sunlight. Recently, two-dimensional (2D) materials have attracted particularfocus because of their charming properties. We report on a novel class of twodimensionalphotocatalysts for hydrogen generation via water splitting. In thispaper, by Density Functional Theory (DFT) calculations, we investigated Hf2CO2 astwo-dimensional transition metal carbides, referred to as MXene, to understandits photocatalytic properties. Using this method, we theoretically investigatedthe structural, electronic, and optical properties of MXene-based nanostructuressuch as Hf2CO2 that were calculated using GGA-PBE and HSE06 functionals. The latticeconstant for GGA-PBE functional for Hf2CO2 is 3.3592A°. The calculated band gapsfor GGA-PBE and HSE06 functionals for two-dimensional Hf2CO2 MXene were 0.92and 1.75 eV, respectively. This MXene-based nanostructure also exhibits excellentoptical absorption performance. Hence, Hf2CO2 is a promising photocatalyticmaterial. پرونده مقاله -
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46 - Employing α-Fe2O3 /Mn2P2O7 as a nano photocatalyst for degradation of toluene in aqueous environment
Sajjad Mafi Kazem MahanpoorIn this study, α-Fe2O3 nano-spheres are immobilized on the surface of manganese pyrophosphate(Mn2P2O7) support using forced hydrolysis and reflux condensation (FHRC) method. The synthesizedα-Fe2O3/Mn2P2O7 were characterized by FTIR, SEM, BET EDX, and XRD. Th چکیده کاملIn this study, α-Fe2O3 nano-spheres are immobilized on the surface of manganese pyrophosphate(Mn2P2O7) support using forced hydrolysis and reflux condensation (FHRC) method. The synthesizedα-Fe2O3/Mn2P2O7 were characterized by FTIR, SEM, BET EDX, and XRD. The photocatalytic activity fromα-Fe2O3/Mn2P2O7 was investigated for the removal of toluene in aqueous solution by UV/H2O2 system. Thechemical oxygen demand (COD) measurements were used to determine the amount of toluene removal.The experiments were designed based on four affecting variables, including pH, catalyst content, initialtoluene concentration and H2O2 at three levels using Box-Behnken experimental design. The results ofthis study showed that α-Fe2O3/Mn2P2O7 as a new photocatalyst has a higher photocatalytic activity thanα-Fe2O3 nanoparticles. Based on the achieved results, the maximum degradation efficiency was 97.14%in optimal conditions. پرونده مقاله -
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47 - ZnO/WO3 nanocomposites: Pechini sol-gel synthesis, characterization, and photocatalytic performance for desulfurization of thiophene
Nahid Kalhor Mohammad Ghodrati Mehdi Mousavi-KamazaniThe aim of this study was to investigate and overcome thiophene sulfurcontaminants using high purity synthesized ZnO/WO3 nanocomposite andhomogeneous composition by Pechini sol-gel method at low temperature.Zinc oxide is one of the most dynamic elements known in this fi چکیده کاملThe aim of this study was to investigate and overcome thiophene sulfurcontaminants using high purity synthesized ZnO/WO3 nanocomposite andhomogeneous composition by Pechini sol-gel method at low temperature.Zinc oxide is one of the most dynamic elements known in this field, itspresence together with tungsten oxide prevents the crystallization of tungstennanoparticles. Fuzzy structure, percentage of elements, surface morphology,penetration reflection spectrum, and photocatalytic degradation of thiophenewere determined by XRD, EDS, SEM, and DRS analyses, respectively. DRS resultsindicate high light absorption, reduced bandgap due to the presence of WO3 aftercombination with ZnO, and increased efficiency. Finally, the nanocomposite withmore than 84% efficiency resulted in the degradation of oxidative desulfurizationof thiophene after 150 min under visible light. پرونده مقاله -
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48 - Taguchi optimization of photodegradation of yellow water of trinitrotoluene production catalyzed by nanoparticles TiO2/N under visible light
Hamid Reza Pouretedal Mohammad Fallahgar Fahimeh Sotoudeh Pourhasan Mohammad NasiriTaguchi experimental design technique was used for optimization of photodegradation of yellow water sample of trinitrotoluene (TNT) production process. The nanoparticles of doped N-TiO2 were also used as photocatalysts in the photodegradation reaction under visible ligh چکیده کاملTaguchi experimental design technique was used for optimization of photodegradation of yellow water sample of trinitrotoluene (TNT) production process. The nanoparticles of doped N-TiO2 were also used as photocatalysts in the photodegradation reaction under visible light. The ranking of data based on signal to noise ratio values showed that the importance order of the factors affecting the degradation efficiency was: the nature of photocatalyst > time of photodegradation > amount of photocatalyst > initial concentration of pollutant. The optimized conditions were photocatalyst of TiO2/N0.1 photocatalyst dosage of 1.5 g L-1 and dilution times of 750 for real samples. The photocatalyst of TiO2/N0.1 was analyzed by BET surface analysis, X-ray diffraction pattern, field emission scanning electron microscopy (FE-SEM), energy-dispersive X-ray spectroscopy (EDS) and diffuse reflectance spectra (DTS). Relatively high surface area of 150 m2×g-1, anatase/rutile structure, approximately uniform distribution of nanoparticles size and band-gap energy of 2.92 eV were measured for TiO2/N0.1 nanophotocatalyst. A linear model with the regression coefficient (R2) of 0.887 was obtained by the multiple linear regression analysis. The proposed model was "Degradation efficiency (Y) = 20.492 +1.461X1 +6.330X2 + 0.014X3 +2.291X4". The obtained P-values in the confidence level of 95% were < 0.05, showing a meaningful addition in the model. Therefore, changes in the predictor’s value are due to changes in the response variable. پرونده مقاله -
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49 - Enhancement of photocatalytic activity of ZnO–SiO2 by nano-sized Pt for efficient removal of dyes from wastewater effluents
Leila Vafayi Soodabe GharibeIn this work, ZnO/SiO2 nanoparticles were prepared using sol-gel method, and platinum particles were loaded on ZnO/SiO2 nanoparticles by photoreductive method. Samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and Fourier transfor چکیده کاملIn this work, ZnO/SiO2 nanoparticles were prepared using sol-gel method, and platinum particles were loaded on ZnO/SiO2 nanoparticles by photoreductive method. Samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FT-IR). The XRD patterns showed that the zinc oxide samples have a wurtzite structure (hexagonal phase). The crystallite size calculated by Scheerer’s equation is ~ 32 nm. For photocatalytic test, decomposition of Rhodamine B (RB), as an organic pollutant, was carried out. A comparison of degradation between bare catalyst and platinum loaded ZnO/SiO2 nanoparticle under UV-Vis light irradiation shows that the Pt- ZnO/SiO2 photocatalyst is more efficient than ZnO/SiO2 nanoparticles. Also, the activity of ZnO/SiO2 nanoparticles in the visible light are minimal, while loading of Pt in zinc oxide network displaced the band gap toward longer wavelengths (visible light) and improved the photocatalysis activity of ZnO/SiO2 in the range of visible light. پرونده مقاله -
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50 - Sonosynthesis, characterization and photocatalytic degradation property of nanoZnO/zeoliteA
Shokufeh Aghabeygi Reza Kia Kojoori Hamideh Vakili AzadNano hexagonal wurtzite ZnO has been prepared on zeoliteA by the sono-chemical method. The zeoliteA was mixed into Zinc gel, after stirring for two days, the mixture was irradiated 30 min by ultrasonic probe. The filtrated composite gel was calcinated at 500°C for 3 چکیده کاملNano hexagonal wurtzite ZnO has been prepared on zeoliteA by the sono-chemical method. The zeoliteA was mixed into Zinc gel, after stirring for two days, the mixture was irradiated 30 min by ultrasonic probe. The filtrated composite gel was calcinated at 500°C for 3h in furnace. The produced composite was characterized using X-ray diffraction, FT-IR spectroscopy and field emission scanning electron microscopy. The average crystal size of the nanoZnO and nanoZnO on zeoliteA was determined 53 and 38 nm, respectively. The range of particles size of the nanoZnO on zeoliteA is 30-50 nm. The particles of nanoZnO on the surface of zeoliteA has been dispersed over the zeoliteA framework and the results have shown a higher rate of photodegradation of Congo red (an azo-dye) as compared with bare nanoZnO. پرونده مقاله -
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51 - Optimization and modeling of photocatalytic degradation of Direct Blue 71 from contaminated water by TiO2 nanoparticles: Response surface methodology approach (RSM)
Mohamadreza Massoudinejad Mohsen Sadani Zeinab Gholami Zeinab Rahmati Masoume Javaheri Hassan Keramati Mansour Sarafraz Moayed Avazpour Sabah ShiriIn the current survey, the removal of dye from contaminated water was studied by photocatalytic degradation using TiO2 nanoparticles with respect to pH, TiO2 dosage, reaction time, temperature and initial dye concentration. TiO2 nanoparticles were investigated by XRD, F چکیده کاملIn the current survey, the removal of dye from contaminated water was studied by photocatalytic degradation using TiO2 nanoparticles with respect to pH, TiO2 dosage, reaction time, temperature and initial dye concentration. TiO2 nanoparticles were investigated by XRD, FESEM and FT-IR.The RSM was chosen to study the composition effects of input independent factors and one dependent output response (removal efficiency). The P-value (2.2 × 10−16), F-value (1832), R2 (multiple R-squared: 0.9985, adjusted R-squared: 0.9972), and lack of fit (0.432) indicate that the reduced full second order model is highly significant for dye removal by TiO2 nanoparticles.The maximum percentage removal of dye, 90.2%, was achieved at optimum operating conditions including pH=6.5, TiO2 dose (1.2 g L-1), contact time (67.5 min), temperature ( ), and dye concentrations (55 mg L-1)), respectively.The maximum removal efficiency was calculated to be 100%, using regression coefficients derived from the model and the Solver “Add-ins”.The results indicated that the TiO2 photocatalyst was very proper for the removal dye from contaminated water, and it had good efficiency in eliminating textile dyes. پرونده مقاله -
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52 - Enhanced removal of methylene blue dye by bimetallic nano-sized MOF-5s
Mahshid Zebardast Abdollah Fallah Shojaei Khalil TabatabaeianMetal-organic framework 5 (MOF-5) and bimetallic MOF-5s (Co/Zn and Ni/Zn) were prepared via a simple solvothermal method. Samples were characterized by various techniques such as powder X-ray diffraction (XRD), Fourier transform infrared (FT-IR), scanning electron micro چکیده کاملMetal-organic framework 5 (MOF-5) and bimetallic MOF-5s (Co/Zn and Ni/Zn) were prepared via a simple solvothermal method. Samples were characterized by various techniques such as powder X-ray diffraction (XRD), Fourier transform infrared (FT-IR), scanning electron microscopy (SEM), UV-Vis diffuse reflectance spectroscopy (DRS), inductively coupled plasma (ICP) and elemental analysis (EA). Photocatalytic decolorization of methylene blue (MB) dye in the aqueous solutions was examined under UV and visible light irradiation. The degradation of MB solutions was calculated by changes in the UV–Vis absorbencies of the aqueous solutions at λmax = 664 nm. The influence of various parameters such as the catalyst loading, dye concentration, initial pH of the dye solution and adding electron acceptors (H2O2, tert-Butyl hydroperoxide (TBHP), KBrO3, KIO4 and (NH4)2S2O8) on the degradation reaction was studied. Moreover, metal doping can improve the photocatalytic activity of MOF-5 due to the synergistic effect, narrow band gap and so on. The results show that Co/Zn-MOF-5 photocatalyst exhibited better photocatalytic activitythan Ni/Zn-MOF-5 and raw MOF-5 for MB decolorization under UV and visible light irradiation. Furthermore, adding different electron acceptors, except TBHP, enhanced the photocatalytic performance of photocatalysts with a different rate. Also, kinetic studies revealed that the reactions follow pseudo-first-order. Additionally, bimetallic MOF-5s did not show obvious activity reduction in MB decolorization during five recycling usages. پرونده مقاله -
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53 - Optical and photocatalytic properties Undoped and Mn-doped ZnO nanoparticles synthesized by hydrothermal method: Effect of annealing temperature
Maryam Bordbar Seyed Mohammad Vasegh Somaye Jafari Ali Yeganeh FaalUndoped and Mn-doped ZnO nanoparticles were successfully prepared by the hydrothermal method with different annealing temperature conditions. Structural, chemical and optical properties of the samples were studied by X-ray diffraction (XRD), Field Emission scanning elec چکیده کاملUndoped and Mn-doped ZnO nanoparticles were successfully prepared by the hydrothermal method with different annealing temperature conditions. Structural, chemical and optical properties of the samples were studied by X-ray diffraction (XRD), Field Emission scanning electron microscopy (FESEM), UV-Vis spectrophotometry and Fourier transform infrared (FT-IR) spectroscopy. The phase purity was confirmed by X-ray powder diffraction (XRD) and XRD spectra showed that all the samples were hexagonal wurtzite structure and as the annealing temperature increases the material becomes less crystalline. In addition, the average crystal size was found to be 15-30 nm from SEM and XRD. It is seen that the optical band gap increases when the ZnO is doped with manganese and decreases when annealing temperature increases. The photoacatalytic activity of Undoped and Mn-doped ZnO nanoparticles was tested by the degradation of metyl orang (MO) under UV light and indicated that Mn-doped ZnO has higher photocatalytic activity relative to ZnO nanoparticles and photocatalytic activity decreases when annealing temperature increases. پرونده مقاله -
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54 - Investigation efficiency of nano photocatalytic compound of TiO2 and rice husk silica in removal of reactive red 198 dye from synthetic aqueous solutions
Abdollrahman Mahmoodi Seyed Mahmood Mehdinia Ayat Rahmani Hamidreza NassehiniaThis study was performed with the aim of investigating the efficiency of the Nano photocatalytic of ultraviolet and titanium dioxide compound and rice husk silica adsorbent (UV/TiO2/RHS) in removal reactive red 198 dye from synthetic aqueous solutions. The removal of re چکیده کاملThis study was performed with the aim of investigating the efficiency of the Nano photocatalytic of ultraviolet and titanium dioxide compound and rice husk silica adsorbent (UV/TiO2/RHS) in removal reactive red 198 dye from synthetic aqueous solutions. The removal of reactive red 198 dye was done in batch reactors with a volume of 250 ml using RHS deposited by titanium dioxide in the presence of a UV lamp. The effect of pH, immobilization of TiO2 on RHS adsorbent, contact time, nanoparticle mass and initial concentration of dye in removal efficiency were investigated. The results of this research showed that with an increase in pH and alkalinity of the solution, the removal efficiency declined. As the pH changed from 3 to 9, the removal efficiency in UV/TiO2/RHS, RHS adsorbent and UVC radiation declined from 75.25 to 27.87, 8.37 to 3.4, and 16.62 to 3.25%, respectively. The maximum dye removal efficiency obtained by UV/TiO2/RHS was as large as 87.5% under pH=3, contact time of 60 min, nanoparticle mass of 1 g/L, and 25 mg/L concentration of the reactive red 198 dye. Therefore, the rice husk silica as a natural adsorbent in combination with (TiO2/UV) can be used as an effective method for removal reactive red of aqueous solutions on a larger scale by optimizing the parameters affecting the removal efficiency. پرونده مقاله -
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55 - Inactivation of Fecal coliforms during solar and photocatalytic disinfection by zinc oxide (ZnO) nanoparticles in compound parabolic concentrators (CPCs)
Ahmadreza Yazdanbakhsh Kourosh Rahmani Hasan Rahmani Mansour Sarafraz Masoumeh Tahmasebizadeh Ayat RahmaniWater samples of 0, 50, and 100 nephelometric turbidity units (NTU) spiked with fecal coliforms (107 CFU/ml) were exposed to natural sunshine in 1l quartz glass tubes fitted with rectors’ compound parabolic concentrators CPCS at two forms CPC1 (whit nanoparticle z چکیده کاملWater samples of 0, 50, and 100 nephelometric turbidity units (NTU) spiked with fecal coliforms (107 CFU/ml) were exposed to natural sunshine in 1l quartz glass tubes fitted with rectors’ compound parabolic concentrators CPCS at two forms CPC1 (whit nanoparticle zinc oxide) and CPC2(without nanoparticle zinc oxide). The samples were characterized using the X-ray powder diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscope (TEM). On clear days, the complete inactivation times (more than 7-log unit reduction in bacterial population) in the systems with CPC1, and CPC2 were 15, and 30 min, respectively. The maximum temperatures obtained in the water samples were 80 for CPC1, and 82 for CPC2. The use of CPC1 with hydroxyl radicals (OH•) production significantly improved the efficiency of the old CPCS technique, since these systems (CPC1-2) shortened the exposure times to solar radiation and also minimized the negative effects of turbidity and also regrowth was zero in the disinfected samples. Due to two simultaneous effects of high temperatures and UV, regrowth in most ways of solar disinfection was not seen in these examples. Overall, this technology has been proved to be a good enhancement method to inactivate microorganisms under real conditions and represents a good alternative technique to drinking water treatment. پرونده مقاله -
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56 - Photo Catalysis Desulfurization at Copper Oxides /Titanium Oxide Nanotubes Under UV and Visible Light Irradiation
Hameed Hussein AlwanTitanium dioxide nanotubes TNTs were synthesized by anodization in a fluoride-based electrolyte, TNTs are commonly working as photocatalytic under ultraviolet UV irradiation via its wide bandgap, and it was expanded under visible light irradiation by doping with other m چکیده کاملTitanium dioxide nanotubes TNTs were synthesized by anodization in a fluoride-based electrolyte, TNTs are commonly working as photocatalytic under ultraviolet UV irradiation via its wide bandgap, and it was expanded under visible light irradiation by doping with other metals or metals oxides, herein TNTs were doped by copper oxides Cu2O and CuO to produce copper oxides /titanium oxide nanotubes CuOx /TNT. The prepared catalysts (TNTs and CuOx/TNT) were characterized by XRD, FTIR, SEM and, EDX, while catalysts activity was investigated for oxidization of Dibenzothiophene DBT under ultraviolet UV and visible light VL irradiations, the feedstock is model fuel (heptane contains DBT as a sulfur component) was oxidized by hydrogen peroxide H2O2. Results showed that TNT has a moderate catalysis effect under UV irradiation and a low catalysis effect under VL irradiation. CuOx/TNT catalyst exhibited good sensitivity for VL radiation. The study investigated the effect of initial DBT concentration, oxidant dosage, reaction temperature, contact time, and type of irradiation on oxidation desulfurization ODS reaction by using TNT and CuOx/TNT catalysts, the results showed that DBT removal efficiency was increasing with temperature (56.2, 80.4 and 91.2 at 40,50, and 60 °C respectively at 100 minutes) and oxidant amount ( 66.4, 80.4, and 86.1 by adding 5,10,15 ml of oxidant respectively at 100 minutes) while it decreases with the increasing initial BDT concentration (94.8, 80.4, and 86.1 when using 100,150, and 200 ppm as initial DBT concentration at 100 minutes). The kinetics calculations exhibited that ODS reaction under VL irradiation follows pseudo-first-order reaction at CuOx/TNT catalyst with reaction rate constants of 0.00076, 0.0108, and 0.0141 min-1 at 40,50, and 60°C respectively, the activation energy for the reaction is 26.8 kJ/mol, negative ΔS (-0.218 kJ/mol.K) and positive ΔH and ΔG for DBT oxidation under UV irradiation. پرونده مقاله -
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57 - Preparation of α-Fe2O3 Nano-photocatalyst supported on Cd(II)-Terephthalic MOF for photocatalytic removal of Cefazolin aqueous solution
Seyed Kamal Blourfrosh Kazem MahanpoorThe main purpose of this study was to investigate the photocatalytic decomposition of the antibiotic Cefazolin (CFZ) from aqueous solutions using a new effective catalyst. This catalyst was made of α-Fe2O3-supported nanoparticles on a metal-organic framework (MOF) چکیده کاملThe main purpose of this study was to investigate the photocatalytic decomposition of the antibiotic Cefazolin (CFZ) from aqueous solutions using a new effective catalyst. This catalyst was made of α-Fe2O3-supported nanoparticles on a metal-organic framework (MOF). The synthesis of Nano α-Fe2O3 photocatalyst was performed by the reflux condensation method. The MOF was synthesized using Cadmium nitrate and Terephthalic acid and Nano α-Fe2O3 supported on MOF using a solid-state distribution (SSD) method. FTIR, XRD, SEM, EDX, N2 adsorption-desorption and TGA technique were used for the identification of the catalyst. Analysis of these results revealed that α-Fe2O3 circular nanoparticles bonded together and occupy a large area on the MOF crystal surfaces. The BET surface area and the pore diameter of the catalyst obtained were 479 m2g-1 and 3.86 nm respectively. UV/H2O2 photocatalytic processes were applied for the decomposition of CFZ from aqueous solutions. This process was optimized and modeled using the full factorial method. Initial concentrations of CFZ, pH, α-Fe2O3/MOF amounts and initial concentration of H2O2 were the variables for the determination of optimal conditions and mathematical models. The highest degradation percentage of CFZ in the optimum condition (CFZ=30 ppm, pH=8, H2O2=5ppm, catalyst=150mg.l-1) was 85.88%. This photocatalyst reaction has pseudo-first-order kinetic with a constant rate of 0.0752 min-1 and it also matched the Langmuir–Hinshelwood model. پرونده مقاله -
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58 - A simple synthetic technique to produce ZnO/Fe2O3/Fe3O4 nanostructures and application as a photocatalyst
Nai-Feng Hsu Kuei-Ting HsuIn this study, a simple technique was used for synthesizing one-dimensional ZnO/Fe2O3/Fe3O4 nanostructures (NSs) through heat treatment under vacuum by using a magnetic field at a temperature of 200 °C for 1 h. The photocatalytic effect of the NSs were studied by de چکیده کاملIn this study, a simple technique was used for synthesizing one-dimensional ZnO/Fe2O3/Fe3O4 nanostructures (NSs) through heat treatment under vacuum by using a magnetic field at a temperature of 200 °C for 1 h. The photocatalytic effect of the NSs were studied by decomposing methyl orange (MO) dye (5 mg/L, pH = 8.1) under ultraviolet illumination. The experimental results indicated that a 33-mg/L ZnO/Fe2O3/Fe3O4 NS-containing film on glass could reduce the MO concentration by 37% in 100 min, and the synthesized ZnO/Fe2O3/Fe3O4 NS-containing films could be reused to degrade MO solution. Moreover, 0.1 g/L of ZnO/Fe2O3/Fe3O4 NS-containing powder exhibited an excellent photocatalytic effect and reduced the MO concentration by almost 90% in 100 min. پرونده مقاله -
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59 - Recent Progress in Visible-Light Active (VLA) TiO2 Nano-Structures for Enhanced Photocatalytic Activity (PCA) and Antibacterial Properties: A Review
Kasun Seneviratne Imalka Munaweera Sriyani Peiris Colin Peiris Nilwala KottegodaThe applications of photocatalytic nanomaterial technology received intense scientific focus with the advent of nanotechnology. Applications based on TiO2 nanoparticles have shown promise of photocatalytic efficiency among many semiconductor metal oxides. Titanium dioxi چکیده کاملThe applications of photocatalytic nanomaterial technology received intense scientific focus with the advent of nanotechnology. Applications based on TiO2 nanoparticles have shown promise of photocatalytic efficiency among many semiconductor metal oxides. Titanium dioxide is utilized in many practical applications such as water and air purification, self-cleaning of surfaces, and energy production. The major drawback with TiO2 based photocatalysts is the wide band gap, which requires UV light to produce the electron-hole pairs. This review article focus on techniques/methods to eliminate band gap which reduces photocatalytic efficiency. Application of semiconductor photocatalytic techniques to degrade organic pollutants and their antimicrobial activity is discussed here using model systems. Synthetic and natural nanohybrids are available today and have varying characteristics as options. Recently developed natural mineral based nanohybrids is the new trend in photocatalytic applications. It appears that the removal efficiency of existed photocatalysts is higher than that of synthetic products. Natural nanohybrids carry the advantages of low costs, avoiding extensive synthesizing conditions in future photocatalytic applications. پرونده مقاله -
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60 - Synthesis and Characterization ZnO-Fe2O3 Nanocomposite with Thermal Plasma Method
Mohamad Reza Alikhani Shahrooz Saviz Amir Hossein SariIn the present paper, a novel thermal plasma method is proposed to synthesize ZnO-Fe2O3 nanocomposite, with different percentages of iron, namely 3, 5, and 7%. This method is an efficient feasibility of the Zno-Fe2O3 nanocomposite synthesis. The nanocomposites are synth چکیده کاملIn the present paper, a novel thermal plasma method is proposed to synthesize ZnO-Fe2O3 nanocomposite, with different percentages of iron, namely 3, 5, and 7%. This method is an efficient feasibility of the Zno-Fe2O3 nanocomposite synthesis. The nanocomposites are synthesized by homemade direct current (DC) plasma torch. They are analyzed by different methods. The bandgap is determined by diffuse reflectance spectroscopy (DRS). The photocatalytic performance of Zno-Fe2O3 is evaluated. The results show that the structure of nanoparticles is spherical, which is more favored in the industry. Also, the particle size distribution is uniform. The average size of nanoparticle crystals increases with increasing iron content. Despite the formation of nanocomposites, due to the lack of support for nanoparticles, the results of photodegradation are not satisfactory. پرونده مقاله -
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61 - Highly Porous Bi(III) Modified Rice Husk Silica Photocatalyst for the Photocatalytic Removal of Cationic Methylene Blue
Normawati Jasni Anwar Iqbal N. H. H Abu Bakar Dede Heri Yuli Yanto Hor Jia Yi Noor Haida Mohd Kaus Mohd Norazmi Ahmad Sri MulijaniA series of bismuth-silicate photocatalysts were synthesized via the sol-gel method for photodegradation of methylene blue (MB) under sunlight irradiation, utilizing rice husk ash as a silica precursor. The scanning electron microscopy/energy dispersive X-ray (SEM/EDX) چکیده کاملA series of bismuth-silicate photocatalysts were synthesized via the sol-gel method for photodegradation of methylene blue (MB) under sunlight irradiation, utilizing rice husk ash as a silica precursor. The scanning electron microscopy/energy dispersive X-ray (SEM/EDX) analysis detected Bi content in 3-10 wt% range. Furthermore, it can be seen that the porosity decreased as the Bi concentration increased. The N2 adsorption-desorption analysis indicates the presence of mesopores with an average diameter of 297-554 Å with Brunauer–Emmett–Teller (BET) surface area of 5.6-30.5 m2/g. The photocatalyst with a Bi concentration of 4 wt% (RHSBi-A2) was the most active in the photodegradation of MB; the removal reached 90% within 4 h. The photodegradation is proposed to be driven by superoxide ( ), hydroxyl (•OH) radicals, and hole (h+) based on the valence band (VB) and conduction band (CB) potentials. The porous silica framework is proposed to act as an electron reservoir, allowing better MB adsorption and enhancing light absorption. پرونده مقاله -
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62 - Effectiveness of Ceria and Stania Nanoparticles in Photodegradation Tenoxicam Antibiotics Using UV-H2O2
Hussein Khalaf Randa El-BakiBoth metal oxides, ceria (CeO2) and stania (SnO2) are prepared by precipitation technique using ammonia solution (1:1) and characterized by thermogravimetric analysis (TGA), x-ray powder diffraction (XRD), transmission electron microscope (TEM), nitrogen adsorption-deso چکیده کاملBoth metal oxides, ceria (CeO2) and stania (SnO2) are prepared by precipitation technique using ammonia solution (1:1) and characterized by thermogravimetric analysis (TGA), x-ray powder diffraction (XRD), transmission electron microscope (TEM), nitrogen adsorption-desorption (for the specific surface area determination, SBET) and used in the photodegradation of Tenoxicam (TEN) antibiotics by using ultraviolet irradiation in presence of hydrogen peroxide. The obtained results showed that ceria and stania have a comparable surface area of 12 and 11 m2 g-1, respectively, and the crystallite size measured by XRD was found to be 44 and 18 nm for ceria and stania, respectively. Also, the results show that by increasing the exposure time, the amount of degraded antibiotic was increased. Data obtained show that both oxides, ceria, and stania can be used effectively as catalysts in the photodegrading process as photocatalysts. Stania is faster than ceria to degrade TEN antibiotics. Ceria needs more time than stania to degrade the drug at 100%, in which the TEN is fully degraded in the presence of stania and H2O2 at 40 minutes under certain conditions. پرونده مقاله -
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63 - Enhancing the Photocatalytic Performance of TiO2 Nanoflower Thin Films under Ultraviolet Irradiation
Marwah Kadhim Mazin Mahdi Jalal HassanChemical bath deposition (CBD) was used to prepare titanium dioxide (TiO2) nanocrystalline thin films on glass substrates. The TiO2 nanocrystalline thin films were created, and the Scanning Electron Microscope (SEM) images showed that they developed as nanoflowers and t چکیده کاملChemical bath deposition (CBD) was used to prepare titanium dioxide (TiO2) nanocrystalline thin films on glass substrates. The TiO2 nanocrystalline thin films were created, and the Scanning Electron Microscope (SEM) images showed that they developed as nanoflowers and tiny semi-nanoplate bundles that grew vertically onto the surface of the substrates with uniform distribution. The nanoplate ranges in length from 26 to 149 nm and the average thickness was between 13 and 228 nm. The prepared TiO2 nanoflower thin films have an energy band gap of 3.26 eV, according to optical characteristics. Using various pH values and UV light exposure durations, the photocatalytic activity of the produced TiO2 nanoflower thin films was examined against the methylene blue (MB) dye at room temperature. When irradiation duration and pH were increased, the photodegradation rate of MB dye also increased. After 240 minutes of exposure, the photodegradation rate of MB dye with pH values of 6, 8, 9, 10, and 11 was 51%, 64%, 79%, and 82%, respectively. The kinetic rate constant for photocatalytic degradation of MB dye was determined to be 0.0069, 0.0061, 0.0038, and 0.0028 min-1 for pH values of 11, 9, 8, and 6, respectively. پرونده مقاله -
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64 - Synthesis, characterization and photocatalytic activity of CeO2-SBA-15
Hamid Reza Pouretedal Sara BasatiMesoporous photocatalysts of CeO2/SBA-15 are prepared by two methods of direct synthesis as solvent-usage and solvent-free methods. In solvent-usage method, CeO2/SBA-15 is synthesized in acidic media. While, in solvent-free method, CeO2/SBA-15, has been prepared through چکیده کاملMesoporous photocatalysts of CeO2/SBA-15 are prepared by two methods of direct synthesis as solvent-usage and solvent-free methods. In solvent-usage method, CeO2/SBA-15 is synthesized in acidic media. While, in solvent-free method, CeO2/SBA-15, has been prepared through the novel path of directly grind cerium salt into the as-prepared samples of SBA-15 occluded with template. This method enables a large amount of cerium to be highly dispersed in the channels of mesoporous silica, also saves time and energy. The resulting composites exhibit photocatalytic activity, and the dispersed CeO2 in SBA-15 illustrates a photodegradation of Congo red (CR) in aqueous solution. X-ray powder diffraction, N2 adsorption-desorption and FT-IR spectroscopy are used to characterize the prepared materials. پرونده مقاله -
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65 - Photocatalytic Reduction of CO2 to Formaldehyde: Role of Heterogeneous Photocatalytic Reactions in Origin of Life Hypothesis
Mohammad Khodadadi-MoghaddamPhotocatalytic reduction of carbon dioxide to formaldehyde was investigated on four semiconductor photocatalysts (FeS, FeS/FeS2, NiO and TiO2). The reaction was carried out in continues flow of CO2 gas bubbled into the reactor. Semiconductor photocatalysts were characte چکیده کاملPhotocatalytic reduction of carbon dioxide to formaldehyde was investigated on four semiconductor photocatalysts (FeS, FeS/FeS2, NiO and TiO2). The reaction was carried out in continues flow of CO2 gas bubbled into the reactor. Semiconductor photocatalysts were characterized by X-Ray diffraction (XRD) and Diffuse Reflectance Spectroscopic (DRS) methods. Sulfide ion was used as hole scavenger. The results show that the TiO2 has greater photocatalytic activity compared to the other photocatalysts, for example, maximum formaldehyde concentration were 720 and 380 ppm on TiO2 and NiO, respectively. Addition of carbonate ion causes an increase (around two times) in the concentration of formaldehyde. The yield of the formaldehyde decreased with decreasing concentration of the sulfide ion and the pH of the reaction mixture (from 700 ppm to 500 ppm). This investigation demonstrates that under ultraviolet radiation, carbon dioxide can be reduced to formaldehyde on semiconductor photocatalysts. This reaction could have been a possible chemical route to photosynthesis on the early Earth. پرونده مقاله -
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66 - Photocatalytic efficiency of CuFe2O4 by supporting on clinoptilolite in the decolorization of acid red 206 aqueous solutions
Azar Bagheri Ghomi Vahid AshayeriIn this paper CuFe2O4, nanocrystalline powders were prepared. Also, the supported Cu ferrite was obtained by impregnation of the supports with Cu and Fe nitrates solutions, for calcination temperature 450 ºC. The samples were characterized by X-ray powder diffracti چکیده کاملIn this paper CuFe2O4, nanocrystalline powders were prepared. Also, the supported Cu ferrite was obtained by impregnation of the supports with Cu and Fe nitrates solutions, for calcination temperature 450 ºC. The samples were characterized by X-ray powder diffraction (XRD) and Fourier transform-infrared spectroscopy (FT-IR). Photocatalytic degradation of acid red 206 in water was studied. CuFe2O4 was supported on Clinoptilolite using solid-state dispersion (SSD) method. The results show that the CuFe2O4/zeoliteis an active photocatalyst. The maximum effect of photodegradation was observed at 10 wt. %CuFe2O4, 90 %wt. Clinoptilolite. A first order reaction with k = 0.123 min-1 was observed. The effects of some parameters such as pH, amount of photocatalyst, initial concentration of dye were examined. پرونده مقاله -
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67 - Preparation, characterization and determination of photocatalytic activity of MCM-41/ZnO and MCM-48/ZnO nanocomposites
Hamid Reza Pouretedal Mina AhmadiThe direct and indirect methods in solvent media and grinding method in a solvent-free media were used to prepare the MCM-41/ZnO and MCM-48/ZnO photocatalysts. The X-ray diffraction (XRD) patterns showed that zinc oxide nanoparticles were put into MCM-41 and MCM-48 subs چکیده کاملThe direct and indirect methods in solvent media and grinding method in a solvent-free media were used to prepare the MCM-41/ZnO and MCM-48/ZnO photocatalysts. The X-ray diffraction (XRD) patterns showed that zinc oxide nanoparticles were put into MCM-41 and MCM-48 substrates and there were ZnO crystallites as secondary phase in the extra framework of mesoporous materials. The decrease of surface areas, pore volume and average pore size of mesoporous materials with incorporation of ZnO nanoparticles were confirmed by N2 adsorption and desorption isotherms. The FT-IR spectra showed an absorption peak at 490 cm-1 that was related to formation of ZnO in the substrate of MCMs. The photocatalytic activity of MCM-41/ZnO and MCM-48/ZnO were studied in photodegradation reaction of Congo red as a dye pollutant. The photocatalysts of MCM-41/ZnO and MCM-48/ZnO which were prepared by grinding method showed the highest photocataltyic activity with pseudo first-order kinetic rate constants of 34.6 and 27.810-3 min-1, respectively. The obtained results indicated complete incorporation of zinc ions in mesoporous material of MCMs in a solvent-free media. The elimination of solvent and facility of proposed method were the advantages of grinding method in preparation of MCM/ZnO photocatalyst. پرونده مقاله -
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68 - سنتز نانوذره های NiO دوپه شده با Cu (II) با آسیاب گلوله سیاره‌ای و شناسایی آن
الهام سجادی مسیح دربندیدر این پژوهش، ابتدا نانوذره های میان متخلخل نیکل هیدروکسید با روش حلال گرمایی سنتز؛ سپس، به عنوان ماده اولیه با حفظ ساختار و ریخت در یک عملیات گرمایی به نانوذره های نیکل اکسید تبدیل شدند. پس ازآن، به وسیله یک آسیاب گلوله ای با مس (П) دوپه شد. ازآن جایی که در طی فرایند چکیده کاملدر این پژوهش، ابتدا نانوذره های میان متخلخل نیکل هیدروکسید با روش حلال گرمایی سنتز؛ سپس، به عنوان ماده اولیه با حفظ ساختار و ریخت در یک عملیات گرمایی به نانوذره های نیکل اکسید تبدیل شدند. پس ازآن، به وسیله یک آسیاب گلوله ای با مس (П) دوپه شد. ازآن جایی که در طی فرایند سنتز از هیچ ماده شیمیایی سمی، گران قیمت و پیچیده استفاده نشد، نتیجه های این پژوهش می تواند از نظر علمی و صنعتی در تولید سایر نانومواد دوپه شده به کارگرفته شود. برای مطالعه های ساختاری و ترکیب شیمیایی نانومواد سنتزشده، روش‌های میکروسکوپی الکترونی روبشی (SEM)، پراش پرتو ایکس (XRD)، طیف سنجی تفکیک انرژی (EDS) و اندازه گیری مساحت سطح و تخلخل سنجی با روش جذب و واجذب نیتروژن (BET) به¬کارگرفته شد. الگو‌های XRD ساختار FCC نانوذره های سنتزشده و عدم وجود فاز ناخالصی را نشان دادند. همچنین، اندازه گیری‌های BET میان متخلخل بودن نانوذره ها، سطح ویژه و حجم منافذ مناسبی را نشان داد. همچنین، رفتار کاتالیستی نانوذره های نیکل اکسید دوپه شده با مس در حذف و تخریب سونوفتوکاتالیستی آلاینده فنل تحت نور مرئی و امواج فراصوت مطالعه شد. ماده فنل محلول در آب به عنوان آلاینده مدل پس از افزودن کاتالیست نیکل اکسید دوپه شده با مس، تحت نور مرئی و امواج فراصوت در مدت ۶0 دقیقه، حدود 5/86 درصد تخریب شد. پرونده مقاله -
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69 - حذف آنیلین از آب‌های آلوده با فرایند اکسایش فوتوکاتالیستی درحضور روی اکسید بارگذاریشده با کربن
پروانه نخستین پناهی افسانه نیکوآنیلین سمیت بالایی دارد که به سرعت از راه پوست جذب می‎شود و در صورتی‎ که بلعیده و یا بخار آن تنفس شود، کشنده است. بنابراین، نظر به مشکلاتی که آنیلین برای محیط‎ زیست و سلامتی انسان ایجاد می‎کند، لازم است که از انتشار این ترکیب به محیط‎زیست جلوگیری شود چکیده کاملآنیلین سمیت بالایی دارد که به سرعت از راه پوست جذب می‎شود و در صورتی‎ که بلعیده و یا بخار آن تنفس شود، کشنده است. بنابراین، نظر به مشکلاتی که آنیلین برای محیط‎ زیست و سلامتی انسان ایجاد می‎کند، لازم است که از انتشار این ترکیب به محیط‎زیست جلوگیری شود. هدف از پژوهش حاضر، حذف آنیلین با فرایند فوتوکاتالیستی تحت پرتو مرئی است. برای این منظور روی اکسید با درصدهای متفاوتی از گرافن و گرافن اکسید کاهش‎یافته، بارگذاری و عملکرد فوتوکاتالیستی آن ها برای حذف آنیلین از محلول آبی در نور مرئی بررسی شد. برای بررسی ویژگی های فیزیکی و شیمیایی چندسازه های به دست آمده نیز با پراش پرتو ایکس، میکروسکوب الکترونی پویشی، فوتولومینسانس، طیف سنجی فروسرخ و طیف سنجی فرابنفش-مرئی بازتاب پخشیده بررسی شد. بررسی فعالیت فوتوکاتالیستی چندسازه ها نشان داد که با بارگذاری گرافن و گرافن اکسید کاهش‎یافته بر روی اکسید‎، درصد حذف آنیلین افزایش و روی اکسید بارگذاری‎شده با ده درصد وزنی گرافن (G(10%wt)/ZnO)، بیشترین فعالیت فوتوکاتالیستی و بازده حذف آلاینده آنیلین (75 درصد حذف) را در نور مرئی از خود نشان داد. پرونده مقاله -
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70 - بررسی تاثیر پیش ماده های مس سولفید و تاثیر نسبت مس سولفید به آهن اکسید در فعالیت فوتوکاتالیستی چندسازه های مغناطیسی CuS/Fe3O4 برای حذف آنیلین زیر تابش نور مرئی
پروانه نخستین پناهی فائزه پیروی محمد حسین رسولی فردآنیلین یکی از ساده ترین ترکیب های آروماتیکی آمینی است که به شدت سمی و استنشاق این ماده موجب التهاب ریه ها می شود و در غلظت های بالا خوردن یا استنشاق بخار آن کشنده است. هدف از پژوهش حاضر، حذف آنیلین با فرایند فوتوکاتالیستی با مس سولفید زیر تابش نور مرئی است. در ابتد چکیده کاملآنیلین یکی از ساده ترین ترکیب های آروماتیکی آمینی است که به شدت سمی و استنشاق این ماده موجب التهاب ریه ها می شود و در غلظت های بالا خوردن یا استنشاق بخار آن کشنده است. هدف از پژوهش حاضر، حذف آنیلین با فرایند فوتوکاتالیستی با مس سولفید زیر تابش نور مرئی است. در ابتدا تاثیر نوع پیش ماده های مس و گوگرد در تهیه مس سولفید بررسی شد، سپس، برای ایجاد ویژگی مغناطیسی در فوتوکاتالیست و جداسازی آسان آن از تعلیقه با آهنربا، چندسازه هایی با نسبت های متفاوت از مس سولفید و Fe3O4 مغناطیسی تهیه شد. برای بررسی ویژگی های فیزیکی و شیمیایی نمونه های تهیه شده از پراش پرتو ایکس، میکروسکوب الکترونی روبشی و طیف سنجی بازتابشی انتشاری فرابنفش-مرئی استفاده شد. بررسی فعالیت فوتوکاتالیستی نشان داد که مس سولفید تهیه شده با مس استات و تیواستامید، بیشترین فعالیت فوتوکاتالیستی را نسبت به مس سولفیدهای تهیه شده با پیش ماده های دیگر از خود نشان می دهد. همچنین، با افزودن Fe3O4 به مس سولفید افزون بر ایجاد ویژگی مغناطیسی، عملکرد فوتوکاتالیستی و در نتیجه درصد حذف آنیلین نیز افزایش می یابد. پرونده مقاله -
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71 - کاهش کربن مونوکسید به هیدروکربن ها با نانوذره های فوتوکاتالیستی پلاسمونی طلا
مریم سلیمانی مریم درگاهی مهدی پورفتحبررسی برهم کنش بین نانوذره های پلاسمونی و گونه جذب شده بر آن برای کاربردهای فوتوکاتالیستی-پلاسمونی بسیار مهم است. شناسایی سازوکار واکنش ها در حالت پایه و تعیین ویژگی نوری در حالت‌های تحریک‌شده، به دلیل مسیرهای پیچیده حامل‌ها، چالش برانگیز است. در این پژوهش، کاهش فوتوکات چکیده کاملبررسی برهم کنش بین نانوذره های پلاسمونی و گونه جذب شده بر آن برای کاربردهای فوتوکاتالیستی-پلاسمونی بسیار مهم است. شناسایی سازوکار واکنش ها در حالت پایه و تعیین ویژگی نوری در حالت‌های تحریک‌شده، به دلیل مسیرهای پیچیده حامل‌ها، چالش برانگیز است. در این پژوهش، کاهش فوتوکاتالیستی کربن مونوکسید (CO) به هیدروکربن ها بر سطح نانوذره های طلا با استفاده از نظریه تابع چگالی بررسی شد. بررسی انرژی‌های آزاد گیبس و سدهای انرژی فعال‌سازی واکنش ها نشان داد که نخستین گام در کاهش مولکول CO تشکیل *CHO به جای *COH است که از راه سازوکار ترجیحی انتقال مستقیم هیدروژن به CO پیش می رود. افزون براین، با محاسبه های نظریه تابع چگالی وابسته به زمان، جذب نوری وابسته به اندازه نانوذره های طلا (ساختار بیست وجهی) با توجه به تشدید پلاسمونی سطحی جای گیر بررسی شد. تجزیه جذب نوری، نوسان گروهی الکترون‌های ظرفیت را در لایه جذب شده مولکول های CO بر نانوذره طلا نشان داد. این مطالعه راهگشای تولید پایدار سوخت با انرژی خورشیدی است. پرونده مقاله -
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72 - سنتز سیلیکون کاربید گرافیتی (g-SiC) متخلخل از ژلاتین و فوم سیلیکا برای حذف فوتوکاتالیستی آلاینده‌های آلی و زیستی آب
مریم افشارپور عارف رستمیدر این پژوهش، سیلیکون کاربید گرافیتی (g-SiC) متخلخل دوپه شده با نیتروژن به عنوان یک فوتوکاتالیست بدون فلز با فوم سیلیکا به عنوان منبع سیلیکون و ژلاتین به عنوان منبع کربنی سنتز شدند. ویژگی فوتوکاتالیستی این ترکیب در حذف فوتوکاتالیستی رنگ های آزو و ازبین بردن باکتری های گ چکیده کاملدر این پژوهش، سیلیکون کاربید گرافیتی (g-SiC) متخلخل دوپه شده با نیتروژن به عنوان یک فوتوکاتالیست بدون فلز با فوم سیلیکا به عنوان منبع سیلیکون و ژلاتین به عنوان منبع کربنی سنتز شدند. ویژگی فوتوکاتالیستی این ترکیب در حذف فوتوکاتالیستی رنگ های آزو و ازبین بردن باکتری های گرم مثبت و منفی در نور مرئی ارزیابی شد. ساختار سنتزی g-SiC توانایی بسیار بالایی را در حذف آلاینده های آلی (99 % در 10 دقیقه) در مقایسه با SiC تجاری (8 % در 10 دقیقه)، نشان داد. این بهبود ویژگی فوتوکاتالیستی به ساختار گرافنی این ترکیب مربوط می شود که موجب افزایش انتقالات الکترونی شده و سرعت بازترکیب را کاهش می دهد. همچنین، به دلیل وجود بار مثبت بر اتم های سیلیکون در ساختار g-SiC، مولکول های اکسیژن محلول در آب می توانند جذب این مراکز شوند و رادیکال های اکسیژنی را تولید کنند. این رادیکال ها می توانند به عنوان یک گونه فعال واکنش های فوتوکاتالیستی را سرعت بخشند. از طرف دیگر، استفاده از فوم سیلیکا موجب افزایش مساحت سطح شد ( m2/g7/191) و با دوپه شدن نیتروژن (8/2 %) ناشی از منبع ژلاتین، نواقص ساختاری بیشتر، قدرت جذب بالاتر و کاف نوار کوچکتر(eV 16/2) در ساختار ایجاد شد که فعالیت فوتوکاتالیستی آن را افزایش داد. نتیجه ها نشان داد که این ترکیب می تواند رنگ های آزو را تا 100 % و باکتری ها را تا بالای 85 % حذف کند. پرونده مقاله -
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73 - تخریب پارانیتروفنل ( PNP ) در محیط آبی با استفاده از فوتوکاتالیست های پایه تنگستن اکسید فعال شده با نور مرئی
فاطمه هدایتی نسب علیرضا زارعی هادی رضایی وحیدیانپارانیتروفنل ( PNP ) به عنوان یک ماده نیتروآروماتیک، از آلایند ههای سمی موجود در پساب های صنعتی است. در این مقاله تخریب این آلاینده به روش فوتوکاتالیستی با استفاده از کاتالیست های Na0.01WO3 ،WO3 و CuWO4/CuO تحت نور مرئی بررسی شده است. کاتالیست های مربوط با روش آب گرمایی چکیده کاملپارانیتروفنل ( PNP ) به عنوان یک ماده نیتروآروماتیک، از آلایند ههای سمی موجود در پساب های صنعتی است. در این مقاله تخریب این آلاینده به روش فوتوکاتالیستی با استفاده از کاتالیست های Na0.01WO3 ،WO3 و CuWO4/CuO تحت نور مرئی بررسی شده است. کاتالیست های مربوط با روش آب گرمایی سنتز شده و فرایند در یک واکنشگاه تعلیقه ای سوسپانسیونی مجهز به یک لامپ متال هالید 400 W انجام شده است. کاتالیست های سنتز شده با استفاده از رو شهای پراش پرتو ایکس XRD ، میکروسکوپ الکترونی روبشی FE-SEM و طیف سنجی بازتاب نفوذی DRS شناسایی شده اند. عامل های مؤثر بر فرایند مانند pH ، دمای واکنش و شدت نور موردبررسی قرار گرفته است. نتایج نشان داد که برای غلظت 2000 ppm از کاتالیست و 20 ppm از PNP ، دمای 25 °C و pH برابر با 5/ 11 ، پس از 240 دقیقه، بازده تخریب با استفاده از کاتالیست های Na0.01WO3 ،WO3 و CuWO4/CuO به ترتیب 40 %، 3/ 42 و 30 % به دست آمد. پرونده مقاله -
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74 - بررسی ویژگی مغناطیسی و فتوکاتالیستی نانوذره‌های Fe3O4 پس از پوشش‌دهی با ZnO و TiO2
سولماز قنبرنژاد علی نعمتی سعید باغشاهی محبوبه محمودیدر این پژوهش، پس از پوشش‌دهی نانوذره‌های مگنتیت با ZnO و TiO2 به روش سل/ژل سعی شد تا تشکیل ساختار و ویژگی مغناطیسی نانوذره‌های هسته/پوسته دو جزیی و سه جزیی با روش پراش پرتو ایکس (XRD)، میکروسکوپ الکترونی عبوری (TEM) و مغناطیس‌سنج ارتعاشی (VSM) بررسی شد. رفتار فتوکاتالیس چکیده کاملدر این پژوهش، پس از پوشش‌دهی نانوذره‌های مگنتیت با ZnO و TiO2 به روش سل/ژل سعی شد تا تشکیل ساختار و ویژگی مغناطیسی نانوذره‌های هسته/پوسته دو جزیی و سه جزیی با روش پراش پرتو ایکس (XRD)، میکروسکوپ الکترونی عبوری (TEM) و مغناطیس‌سنج ارتعاشی (VSM) بررسی شد. رفتار فتوکاتالیستی در تخریب متیلن به لو در گستره صفر تا 120 دقیقه تحت تابش نور خورشید با طیف‌سنج مرئی/فرابنفش ثبت شد. تغییرات با استفاده از طیف فتولامینسانس (PL) و سطح ویژه به‌دست آمده با دستگاه جذب/واجذب نیتروژن (BET) بررسی شد. نتایج به‌دست آمده نشان داد کهmg/ml 10 نانوذره‌های هسته/پوسته بیش از 90 % از مولکول‌های متیلن به لو را در مدت زمان 120 دقیقه تحت تابش نور خورشید تخریب کرده‌اند. اما افزایش تعداد پوسته‌ها سبب تغییر نوع نیم‌رسانا از نوع مستقیم به غیرمستقیم می‌شود که به دنبال آن فصل مشترک ناهمگن رفتار فتوکاتالیستی را تضعیف می‌کند. پرونده مقاله -
دسترسی آزاد مقاله
75 - Degradation of some dyes using nanosized CeCuO3 photocatalyst: synthesis and characterization
Indu Bhati Anil Kumar Suresh C. AmetaCeCuO3 nanoparticles with diameter 4.36 nm was synthesized by a fast and simplemicrowave method using cerric sulphate tetra hydrate and copper sulphate pentahydrate asstarting reagents. CeCuO3 was synthesized under microwave heating for 6 min without calciningsteps. The چکیده کاملCeCuO3 nanoparticles with diameter 4.36 nm was synthesized by a fast and simplemicrowave method using cerric sulphate tetra hydrate and copper sulphate pentahydrate asstarting reagents. CeCuO3 was synthesized under microwave heating for 6 min without calciningsteps. The synthesized products were characterized by X-ray powder diffraction (XRD) andscanning electron microscopy (SEM) and the photocatalytic behaviour of nanosized CeCuO3 wasalso studied spectrophotometrically through decolorization of yellowish orange and fast greendyes, a prompt water pollutant from textile industries. The effect of variation of differentparameters i.e. pH, amount of CeCuO3, concentration of dye and light intensity was observed onthe rate of photocatalytic bleaching. A Tentative mechanism for the photocatalytic bleaching ofdyes has been proposed. پرونده مقاله -
دسترسی آزاد مقاله
76 - Modified Titania Impact on Photocatalytic Efficiency of Bmim [Cl]
Aina Farwizah Shahhiran Raihan Mahirah Ramli Hayyiratul Fatimah Mohd ZaidABSTRACT: Titania has been one of the promising alternatives in treating environmental pollution issues and was considered in various applications due to its flexible behaviour. Many studies have been conducted to test its phase-changing properties and adaptive ability چکیده کاملABSTRACT: Titania has been one of the promising alternatives in treating environmental pollution issues and was considered in various applications due to its flexible behaviour. Many studies have been conducted to test its phase-changing properties and adaptive ability such as calcination process, and metal and nonmetal modification using mono-doped or co-doped elements. In the present study, the photocatalyst was developed from embedment with activated carbon (AC) followed by co-doping of Cu2+ and Fe3+ metal ions. The photocatalyst was characterized by XRD, BET and FESEM. The synthesized photocatalyst was tested in the photocatalytic degradation system for ionic liquid (IL) at the optimized parameters which includes solution pH = 6, [photocatalyst] = 1 g/L and [H2O2] = 0.75 ml/L. The co-doped product exhibited a smaller crystalline sizes as compared to bare TiO2. In addition, copper and iron dopants are well dispersed into the TiO2 lattice as no additional phases were detected. Maximum degradation of 77% of 0.11mM IL was recorded in the Cu:Fe-TiO2/AC system after 240 min of visible light irradiation. The system’s efficiency in terms of tested photocatalysts is in the order of P25 < TiO2 < TiO2/AC < Cu:Fe-TiO2/AC, respectively. پرونده مقاله -
دسترسی آزاد مقاله
77 - ساخت میکروساختار هسته/پوسته/پوسته Fe3O4/SiO2/TiO2 و بررسی خواص ساختاری آن
فردین قاسمی پیرانلو فاطمه باورسی ها سعیده داداشیاندر این تحقیق کامپوزیت Fe3O4/SiO2/TiO2با ساختار هسته- پوسته-پوسته با استفاده از روش شیمیایی تر تهیه شد. ابتدا کامپوزیت Fe3O4/SiO2 با استفاده از پیش ماده تترا اتیل اورتوسیلیکات (TEOS) سنتز شد. سپس یک پوسته از TiO2 به طور مستقیم بر روی آن پوشش داده شد. نانوساختارهای Fe3O4 چکیده کاملدر این تحقیق کامپوزیت Fe3O4/SiO2/TiO2با ساختار هسته- پوسته-پوسته با استفاده از روش شیمیایی تر تهیه شد. ابتدا کامپوزیت Fe3O4/SiO2 با استفاده از پیش ماده تترا اتیل اورتوسیلیکات (TEOS) سنتز شد. سپس یک پوسته از TiO2 به طور مستقیم بر روی آن پوشش داده شد. نانوساختارهای Fe3O4 / SiO2 / TiO2 تهیه شده با استفاده از آنالیزهای میکروسکوپ الکترونی روبشی محیطی (FESEM)، میکروسکوپ الکترونی عبوری (TEM)، الگوی پراش پرتو ایکس (XRD) و دستگاه طیف‌سنجی تبدیل فوریه مادون قرمز (FTIR) مشخصه یابی شدند. نتایج نشان داد که پوشش‌دهی لایه‌های SiO2 و TiO2 با موفقیت انجام شده است. نتایج نشان داد که اندازه ذرات Fe3O4 در حدود 400-300 نانومتر و ضخامت پوشش‌های TiO2 و SiO2 به ترتیب 4 و 30 نانومتر می باشد. خواص مغناطیسی کامپوزیت سنتز شده با استفاده از مغناطیس‌سنج ارتعاشی (VSM) مورد بررسی قرار گرفت. مغناطیس اشباع (Ms) پودر Fe3O4 و کامپوزیت Fe3O4/SiO2/TiO2 به ترتیب emu/g 80 و emu/g 37 و هم چنین میزان پسماند مغناطیسی (Mr) پودر Fe3O4 و کامپوزیت Fe3O4/SiO2/TiO2 به ترتیب emu/g 8 و emu/g 43/6 به دست آمد. پرونده مقاله -
دسترسی آزاد مقاله
78 - مطالعه خواص فیزیکی و مکانیکی پلیاورتان تقویت شده با نانوذرات تیتانیا
صاحبعلی منافی مهدی طلاییدر این پژوهش به بررسی اثر اضافه کردن نانوذرات تیتانیا به پلی‎اورتان پرداخته شده‎ است و اثرات مکانیکی و شیمیایی آن مورد ارزیابی قرار گرفته است. نانوذرات اضافه شده به ترتیب با درصد وزنی 1/0، 5/0، 1 و 2 درصد وزنی بوده و اثر ساختارهای آناتاز و روتایل بررسی شده‎ا چکیده کاملدر این پژوهش به بررسی اثر اضافه کردن نانوذرات تیتانیا به پلی‎اورتان پرداخته شده‎ است و اثرات مکانیکی و شیمیایی آن مورد ارزیابی قرار گرفته است. نانوذرات اضافه شده به ترتیب با درصد وزنی 1/0، 5/0، 1 و 2 درصد وزنی بوده و اثر ساختارهای آناتاز و روتایل بررسی شده‎اند. پس از مخلوط کردن نانوذرات تیتانیا با رنگ پلی‎اورتان، مواد حاصله را به مدت h 2 با همزن آلتراسونیک، h 3 با همزن معمولی و سپس به مدت یک ساعت با همزن آلتراسونیک مخلوط کرده و در آخر گاززدایی می‎شود. به خاطر کاهش میزان آگلومره، از پراکنده‎ساز متناسب با دستورالعمل شرکت سازنده استفاده شده ‎است. نانوکامپوزیت به دست آمده به ضخامت µm 90 روی نمونه‎ها اعمال می‎شود. نمونه‎ها جهت آزمون‎های مقاومت به اشعه UV و مقاومت شیمیایی و مکانیکی تحت آزمایش قرار می‎گیرند. نتایج به دست آمده نشان دهنده ‎این مطلب است که با اضافه کردن 1/0 درصد نانوذرات روتایل بهترین خواص فیزیکی و مکانیکی و مقاومت به اشعه UV حاصل می‎شود. از میکروسکوپ نوری برای بررسی مقدار پراکندگی نانوذرات و از میکروسکوپ AFM برای بررسی مورفولوژی سطح، استفاده گردید. سختی سطح نمونه‎ها و مقاومت به خراش، مقاومت به سایش و همچنین مقاومت به خوردگی آنها نیز مورد ارزیابی قرار گرفتند. نتایج نشان دهنده افزایش مقاومت به اشعه UV، پایداری بیشتر به ثابت ماندن رنگ، افزایش استحکام، سختی، مقاومت به خوردگی، مقاومت به خراشیدگی و افزایش طول عمر است و باعث کاهش هزینه‎های نگهداری و تعمیرات پوشش و همچنین کاهش آسیب به محیط زیست می‎شود. پرونده مقاله -
دسترسی آزاد مقاله
79 - ارزیابی خواص فتوکاتالیزوری و ضد باکتری نانوکامپوزیت ZnO-CuO تولید شده به روش سل- ژل
سیده زهرا انوری محمد حاجب محمود فاضل نجف آبادیدر این تحقیق نانو ذرات CuO، ZnO و نانوکامپوزیت ZnO-CuO با روش سل ژل سنتز شد. ویژگی‌های محصولات سنتز شده با استفاده از آزمون‌های XRD، DRS-UV و FESEM ارزیابی شد. نتایج تجزیه و تحلیل XRD نشان داد که نانو ذرات CuO، ZnO و کامپوزیت ZnO-CuO کریستالی بوده و آمورف نیست. نتایج تج چکیده کاملدر این تحقیق نانو ذرات CuO، ZnO و نانوکامپوزیت ZnO-CuO با روش سل ژل سنتز شد. ویژگی‌های محصولات سنتز شده با استفاده از آزمون‌های XRD، DRS-UV و FESEM ارزیابی شد. نتایج تجزیه و تحلیل XRD نشان داد که نانو ذرات CuO، ZnO و کامپوزیت ZnO-CuO کریستالی بوده و آمورف نیست. نتایج تجزیه و تحلیل DRS-UV نشان داد که به ترتیب CuO، ZnO و نانوکامپوزیت ZnO-CuO دارای متوسط انرژی شکاف باند 27/1 و 21/3 و 43/2 الکترون ولت هستند. محاسبات نشان داد ترکیبات CuO و ZnO و کامپوزیت ZnO–CuO در اثر تابش نور می‌تواند به ترتیب 40، 10 و 68% از آلاینده‌ی رنگی رودامین B را تخریب نماید؛ بنابراین کامپوزیت نمودن ZnO با CuO سبب افزایش فعالیت فتوکاتالیزوری محصولات شد. همچنین مکانیسم فعالیت فتوکاتالیزوری محصولات سنتز شده و نقش اکسید مس در افزایش بازه فرآیند فتوکاتالیزوری مورد بحث قرار گرفته است. ارزیابی خواص ضد باکتری نشان داد نانو کامپوزیت ZnO-CuO دارای توانایی ضد باکتریایی علیه استافیلوکوکوس آرئوس به‌عنوان باکتری گرم مثبت و اشریشیاکلی به‌عنوان باکتری گرم منفی است. پرونده مقاله -
دسترسی آزاد مقاله
80 - سنتز با روش سونوشیمی نانوکامپوزیت سولفیدروی-اکسیدآهن دوپ شده با یوروپیوم با عملکرد فتوکاتالیستی بالا در حذف آلاینده آلی رنگی
شیرین کلانتری علی شکوه فردر این تحقیق هدف سنتز نانوکامپوزیتی با خاصیت فتوکاتالیستی بالا و قابلیت جدایش مغناطیسی به ترتیب به منظور تخریب آلاینده آلی و استفاده مجدد است. بدین ترتیب نانوکامپوزیت سولفیدروی-اکسیدآهن دوپ شده با یوروپیوم با روش سونوشیمی سنتز شد که روشی آسان و کم هزینه است. فتوکاتالیست چکیده کاملدر این تحقیق هدف سنتز نانوکامپوزیتی با خاصیت فتوکاتالیستی بالا و قابلیت جدایش مغناطیسی به ترتیب به منظور تخریب آلاینده آلی و استفاده مجدد است. بدین ترتیب نانوکامپوزیت سولفیدروی-اکسیدآهن دوپ شده با یوروپیوم با روش سونوشیمی سنتز شد که روشی آسان و کم هزینه است. فتوکاتالیست بعد از آماده سازی با روش های آنالیز پراش سنجی پرتو ایکس (XRD)، میکروسکوپ الکترونی روبشی نشر میدانی (FE-SEM)، طیف سنجی پراکندگی انرژی پرتو ایکس (EDS)، طیف سنجی فوتولومینسانس (PL)، طیف نورسنج UV ارزیابی شد. قابلیت جدایش مغناطیسی فتوکاتالیست در حضور آهنربا بررسی شد و درصد بالایی از فتوکاتالیست جذب آهنربا شد، بنابراین قابلیت استفاده مجدد امکان پذیر می باشد. عملکرد فتوکاتالیستی در حضور نانوکامپوزیت سنتز شده برای تخریب رنگ ردامین-بی تحت نور UV-C و مرئی بررسی شد، نتایج بازده تخریب 81% و 78% به ترتیب در حضور لامپ UV-C بعد از 3 ساعت تابش و لامپ مرئی بعد از 1 ساعت تابش را نشان داد. به علاوه آزمایش پایداری و استفاده مجدد نشان داد که نانوکامپوزیت همچنان بعد از 3 سیکل ظرفیت فتوکاتالیستی خود را حفظ می کند. پرونده مقاله -
دسترسی آزاد مقاله
81 - Organic compound removal from textile wastewater by photocatalytic and sonocatalytic processes in the presence of copper oxide nanoparticles
Reza Fekri Seyed-Ahmad Mirbagheri ebrahim fataei Gholamreza Ebrahimzadeh-Rajaei Lobat TaghaviThe textile industry is one of the main consumers of water and the wastewater from this industry is one of the main sources of environmental contamination because they can release high levels of organic compounds into the environment. The chemical compounds of the waste چکیده کاملThe textile industry is one of the main consumers of water and the wastewater from this industry is one of the main sources of environmental contamination because they can release high levels of organic compounds into the environment. The chemical compounds of the wastewater, especially polycyclic aromatic hydrocarbons are highly carcinogenic and toxic and must be treated before release to the environment. Photocatalytic and sonocatalytic processes in the presence of metal oxide nanoparticles (NPs) are among the advanced oxidation processes (AOPs) which have found increasing popularity due to their high efficiency and no secondary contamination. In this research, CuO NPs were first synthesized using Peganum harmala seed extract. The samples were then evaluated by SEM, XRD, and EDX tests. The degradation efficiency of organic compounds in textile wastewater was explored by photocatalytic and sonocatalytic processes in the presence of copper oxide NPs. The results indicated that the crystallites of the spherical CuO NPs have an average size of 84 nm. According to GC-MS results, decane, undecane, dodecane, naphthalene, decahydro-2,3-dimethyl, methylmethylenecyclohexane, decahydro-1,5-dimethyl, tridecane, tetradecane, and hexadecane composed about 73% of the initial wastewater sample. 100% of 2-methylmethylenecyclohexane, naphthalene, decahydro-1,5-dimethyl, hexadecane, and decahydro-2,3-dimethyl were eliminated by photocatalytic process. The highest (84%) and lowest (52%) sonocatalytic degradation were reported for naphthalene and/or decahydro-2,3-dimethyl, and dodecane, respectively. These values reached about 100% in photocatalytic degradation. UV waves were generally more efficient at removing organic compounds than US treatment. پرونده مقاله
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