سنتز نانوذرات اکسید روی دوپ شده توسط نقره به روش سل-ژل پکینی و مشخصهیابی و بررسی خواص فوتوکاتالیستی انها
محورهای موضوعی : سنتز موادحمیدرضا یوسفی 1 , بابک هاشمی 2
1 - مهندسی مواد-دانشکده مهندسی مواد- دانشگاه شیراز- شیراز-ایران
2 - مهندسی مواد- بخش مهندسی مواد- دانشگاه شیراز- شیراز- ایران
کلید واژه: ZnO, فوتوکاتالیست, Ag, فوتولومینسانس,
چکیده مقاله :
اکسید روی (ZnO)نیمه هادی اکسیدی است که خواص فوتوکاتالیستی داشته و قابلیت تجزیه مواد آلی و تصفیه پساب های صنعتی را دارا می باشد. در این تحقیق نانوذرات اکسیدروی دوپ شده با درصدهای متفاوت نقره (Ag) به روش سل-ژل پکینی برای بررسی خواص فوتوکاتالیستی سنتز گردید. نانو ذرات به دلیل داشتن نسبت سطح به حجم بالا می توانند خواص فوتوکاتالیستی بهتری از خود نشان دهند. همچنین افزودن فلزات نجیب به نیمه هادی می تواند مانع از باز ترکیبی جفت الکترون –حفره گردد. نمونه های سنتز شده حاوی 0/6، 1/8، 3/1 و 6/2 درصد وزنی نقره بودند. نمونه های بدست امده توسط طیف سنج UV-Vis، پراش اشعه X (XRD)، میکروسکوپ الکترونی روبشی (SEM)، میکروسکوپ گسیل میدانی (FESEM)، و طیف سنجی فوتولومینسانس(PL) مشخصه یابی گردیدند. در نهایت از نمونه های سنتز شده نسبت به زمان تست فوتوکاتالیستی در برابر متیلن آبی به انجام شد. با توجه به نتایج مشاهده گردید با دوپ نمودن نقره اندازه ذرات اکسید روی کاهش می یابد همچنین با افزودن نقره به نانوذرات ZnO تا حدود 1/8 درصد وزنی کاهش محسوسی در شدت فوتولومینسانس نمونه ها در محدوده فرابنفش ایجاد شده که نشان دهنده کاهش نرخ بازترکیبی الکترون-حفره و به دنبال ان افزایش نرخ فوتوکاتالیستی نمونه ها می باشد. تکرارپذیر بودن خصلت رنگبری فوتوکاتالیست سنتز شده بوسیله تکرار سه سیکل فوتوکاتالیستی بر روی نمونه دوپ شده با 1/8 درصد وزنی نقره انجام شد، مشاهده گردید که راندمان کاتالیست سنتز شده کاهش چشمگیری نداشته و این نشان دهنده پایداری فوتو کاتالیست سنتز شده است.
Zinc oxide is a semiconductor which has photo-catalyst properties and could be used for degradation of organic materials. In this research silver doped zinc oxide nanoparticles were synthesized using Pechini sol-gel method in order to investigate its photo-catalyst properties. Nanoparticles show good photo-catalyst properties due to high surface area to volume ratio and adding of noble metals to semiconductor decreases recombination of electron-hole. Samples with different weight percentages of silver (0.6, 1.8, 3.1 and 6.2) were synthesized. Samples were characterized by UV-Visible spectroscopy, X-Ray Diffraction (XRD), Scanning Electron Microscope (SEM), Field Emission Scanning Electron Microscope (FESEM), Energy-Dispersive X-ray spectroscopy and Photo luminance Spectroscopy. Photo-catalyst properties of samples were analyzed by degradation of methylene blue. Results showed that Ag doping decreased the particle size of samples and the sample containing 1.8% Ag had maximum rate in degradation of methylene blue solution and this was coincidence with PL results. Adding of Ag to ZnO decreased recombination rate of electron-hole in oxide and therefore increased photo-catalyst properties of samples or degradation rate of solutions. To confirm the decolorization repeatability of the synthesized samples, three photocatalytic cycles were performed on the sample containing 1.8% wt% of silver. It was observed that the decolorization efficiency of sample was not significantly reduced, and it is indicate that the synthesized catalyst is stable and functional.
[1] Z. Han, L. Ren, Z. Cui, C. Chen, H. Pan & J. Chen, “Ag/ZnO flower heterostructures as a visible-light driven photocatalyst via surface plasmon resonanceˮ, Applied Catalysis B: Environmental, Vol. 126, pp. 298-305, 2012.
[2] P. Tanniratt, T. Wasanapiarnpong, C. Mongkolkachit & P. Sujaridworakun, “Utilization of industrial wastes for preparation of high performance ZnO/diatomite hybrid photocatalystˮ, Ceramics International, Vol. 42, No. 15, pp. 17605-17609, 2016.
[3] B. Rajbongshi, A. Ramchiary, B. Jha & S. Samdarshi, “Synthesis and characterization of plasmonic visible active Ag/ZnO photocatalystˮ, Journal of Materials Science: Materials in Electronics, Vol. 25, No. 7, pp. 2969-2973, 2014.
[4] پ. فردین قاسمی، ف. باورسی ها و د. سعیده، "ساخت میکروساختار هسته/پوسته/پوسته Fe3O4/SiO2/TiO2 و بررسی خواص ساختاری آن"، فرآیند های نوین در مهندسی مواد، سال یازدهم، صفحه 143-150، 1396.
[5] C. Jaramillo Páez, J. Navío, M. Hidalgo & M. Macías, “High UV-photocatalytic activity of ZnO and Ag/ZnO synthesized by a facile methodˮ, Catalysis Today, Vol. 284, pp. 121-128, 2017.
[6] ح. اعظم، ج. مجید و ت. علی صفار، "سنتزو مشخصه یابی ریزساختاری نانوکامپوزیت سه تایی SiO2-Al2O3-ZnO تولید شده به روش سل-ژل"، فرآیند های نوین در مهندسی مواد، سال نهم، شماره 32، صفحه 163-172، 1394.
[7] H. Zhai & et al., “Facile one-step synthesis and photoluminescence properties of Ag–ZnO core–shell structureˮ, Journal of Alloys and Compounds, Vol. 600, pp. 146-150, 2014.
[8] M. R. D. Khaki, M. S. Shafeeyan, A. A. A. Raman & W. M. A. W. Daud, “Application of doped photocatalysts for organic pollutant degradation-A reviewˮ, Journal of Environmental Management, Vol. 198, pp. 78-94, 2017.
[9] S. Sagadevan, K. Pal, Z. Z. Chowdhury & M. E. Hoque, “Structural, dielectric and optical investigation of chemically synthesized Ag-doped ZnO nanoparticles compositesˮ, Journal of Sol-Gel Science and Technology, pp. 1-11, 2017.
[10] V. Mohite & et al., “Photoelectrocatalytic degradation of benzoic acid using Au doped TiO 2 thin filmsˮ, Journal of Photochemistry and Photobiology B: Biology, Vol. 142, pp. 204-211, 2015.
[11] M. Kashif, M. Ali, S. M. U. Ali & U. Hashim, “Sol–gel synthesis of Pd doped ZnO nanorods for room temperature hydrogen sensing applicationsˮ, Ceramics International, Vol. 39, No. 6, pp. 6461-6466, 2013.
[12] B. Banerjee, V. Amoli, A. Maurya, A. K. Sinha & A. Bhaumik, “Green synthesis of Pt-doped TiO 2 nanocrystals with exposed (001) facets and mesoscopic void space for photo-splitting of water under solar irradiationˮ, Nanoscale, Vol. 7, No. 23, pp. 10504-10512, 2015.
[13] R. Saravanan & et al., “ZnO/Ag nanocomposite: an efficient catalyst for degradation studies of textile effluents under visible lightˮ, Materials Science and Engineering: C, Vol. 33, No. 4, pp. 2235-2244, 2013.
[14] A. Senthilraja, B. Subash, B. Krishnakumar, D. Rajamanickam, M. Swaminathan & M. Shanthi, “Synthesis, characterization and catalytic activity of co-doped Ag–Au–ZnO for MB dye degradation under UV-A lightˮ, Materials Science in Semiconductor Processing, Vol. 22, pp. 83-91, 2014.
[15] W. Lu, G. Liu, S. Gao, S. Xing & J. Wang, “Tyrosine-assisted preparation of Ag/ZnO nanocomposites with enhanced photocatalytic performance and synergistic antibacterial activitiesˮ, Nanotechnology, Vol. 19, No. 44, pp. 445711, 2008.
[16] Y. Zheng, L. Zheng, Y. Zhan, X. Lin, Q. Zheng & K. Wei, “Ag/ZnO heterostructure nanocrystals: synthesis, characterization, and photocatalysisˮ, Inorganic chemistry, Vol. 46, No. 17, pp. 6980-6986, 2007.
[17] Q. Simon & et al., “Plasma-assisted synthesis of Ag/ZnO nanocomposites: First example of photo-induced H 2 production and sensingˮ, International journal of hydrogen energy, Vol. 36, No. 24, pp. 15527-15537, 2011.
[18] S. A. Ansari, M. M. Khan, J. Lee & M. H. Cho, “Highly visible light active Ag@ ZnO nanocomposites synthesized by gel-combustion routeˮ, Journal of Industrial and Engineering Chemistry, Vol. 20, No. 4, pp. 1602-1607, 2014.
[19] B. L. Cushing, V. L. Kolesnichenko & C. J. O'Connor, “Recent advances in the liquid-phase syntheses of inorganic nanoparticlesˮ, Chemical reviews, Vol. 104, No. 9, pp. 3893-3946, 2004.
[20] J. Wang & et al., “Preparation and photocatalytic properties of magnetically reusable Fe 3 O 4@ ZnO core/shell nanoparticlesˮ, Physica E: Low-dimensional Systems and Nanostructures, Vol. 75, pp. 66-71, 2016.
[21] H. Bouzid, M. Faisal, F. A. Harraz, S. A. Al Sayari & A. A. Ismail, “Synthesis of mesoporous Ag/ZnO nanocrystals with enhanced photocatalytic activityˮ, Catalysis Today, Vol.252, pp. 20-26, 2015.
[22] P. S. S. Kumar, A. Manivel & S. Anandan, “Synthesis of Ag-ZnO nanoparticles for enhanced photocatalytic degradation of acid red 88 in aqueous environmentˮ, Water Science and Technology, Vol. 59, No. 7, pp. 1423-1430, 2009.
[23] L. Xu, G. Zheng, L. Zhao & S. Pei, “Two different mechanisms on UV emission enhancement in Ag-doped ZnO thin filmsˮ, Journal of Luminescence, Vol. 158, pp. 396-400, 2015.
[24] O. Bechambi, M. Chalbi, W. Najjar & S. Sayadi, “Photocatalytic activity of ZnO doped with Ag on the degradation of endocrine disrupting under UV irradiation and the investigation of its antibacterial activityˮ, Applied Surface Science, Vol. 347, pp. 414-420, 2015.
[25] G. Guerguerian & et al., “ZnO nanorod/CdS nanocrystal core/shell-type heterostructures for solar cell applicationsˮ, Nanotechnology, Vol. 22, No. 50, pp. 505401, 2011.
[26] T. Hirakawa & P. V. Kamat, “Charge separation and catalytic activity of Ag@ TiO2 core− shell composite clusters under UV− irradiationˮ, Journal of the American Chemical Society, Vol. 127, No. 11, pp. 3928-3934, 2005.
[27] S. T. Kuo, W. H. Tuan, J. Shieh & S. F. Wang, “Effect of Ag on the microstructure and electrical properties of ZnOˮ, Journal of the European Ceramic Society, Vol. 27, No. 16, pp. 4521-4527, 2007.
[28] C. Karunakaran, V. Rajeswari & P. Gomathisankar, “Optical, electrical, photocatalytic, and bactericidal properties of microwave synthesized nanocrystalline Ag–ZnO and ZnOˮ, Solid State Sciences, Vol. 13, No. 5, pp. 923-928, 2011.
[29] M. Koleva, A. O. Dikovska, N. Nedyalkov, P. Atanasov & I. Bliznakova, “Enhancement of ZnO photoluminescence by laser nanostructuring of Ag underlayerˮ, Applied Surface Science, Vol. 258, No. 23, pp. 9181-9185, 2012.
[30] C. Ren & et al, “Synthesis of Ag/ZnO nanorods array with enhanced photocatalytic performanceˮ, Journal of Hazardous materials, Vol. 182, No. 1-3, pp. 123-129, 2010.
[31] K. Tam & et al., “Defects in ZnO nanorods prepared by a hydrothermal methodˮ, The Journal of Physical Chemistry B, Vol. 110, No. 42, pp. 20865-20871, 2006.
[32] C. Gu, J. Li, J. Lian & G. Zheng, “Electrochemical synthesis and optical properties of ZnO thin film on In 2 O 3: Sn (ITO)-coated glassˮ, Applied surface science, Vol. 253, No. 17, pp. 7011-7015, 2007.
[33] M. S. Hameed, J. J. Princice, N. R. Babu & A. Arunachalam, “Effect of silver doping on optical properties of nanoflower ZnO thin films prepared by spray pyrolysis techniqueˮ, Journal of Materials Science: Materials in Electronics, Vol. 28, No. 12, pp. 8675-8683, 2017.
[34] X. Yang, Y. Wang, L. Xu, X. Yu & Y. Guo, “Silver and indium oxide codoped TiO 2 nanocomposites with enhanced photocatalytic activityˮ, The Journal of Physical Chemistry C, Vol. 112, No. 30, pp. 11481-11489, 2008.
[35] G. Tian, K. Pan, H. Fu, L. Jing & W. Zhou, “Enhanced photocatalytic activity of S-doped TiO 2–ZrO 2 nanoparticles under visible-light irradiationˮ, Journal of hazardous materials, Vol. 166, No. 2, pp. 939-944, 2009.
[36] Y. Li & et al., “Highly efficient visible-light-induced photocatalytic activity of nanostructured AgI/TiO2 photocatalystˮ, Langmuir, Vol. 24, No. 15, pp. 8351-8357, 2008.
[37] S. Gao, X. Jia, S. Yang, Z. Li & K. Jiang, “Hierarchical Ag/ZnO micro/nanostructure: green synthesis and enhanced photocatalytic performanceˮ, Journal of Solid State Chemistry, Vol. 184, No. 4, pp. 764-769, 2011.
[38] M. Raula, M. H. Rashid, T. K. Paira, E. Dinda & T. K. Mandal, “Ascorbate-assisted growth of hierarchical ZnO nanostructures: sphere, spindle, and flower and their catalytic propertiesˮ, Langmuir, Vol. 26, No. 11, pp. 8769-8782, 2010.
[39] F. Xu, Y. Zhang, Y. Sun, Y. Shi, Z. Wen & Z. Li, “Silver nanoparticles coated zinc oxide nanorods array as superhydrophobic substrate for the amplified SERS effectˮ, The Journal of Physical Chemistry C, Vol. 115, No. 20, pp. 9977-9983, 2011.
[40] J. Xie & Q. Wu, “One-pot synthesis of ZnO/Ag nanospheres with enhanced photocatalytic activityˮ, Materials Letters, Vol. 64, No. 3, pp. 389-392, 2010.
_||_