International Journal of Bio-Inorganic Hybrid Nanomaterials: 2 (2)

Open Access Article

1 - Synthesis and investigation of thermal conductivity carbon nanotubes: MWCNT and SWCNT

In this study, Bio-based carbon nanotubes (CNTs) have received considerable research attention due to their comparative advantages of high level stability, simplistic use, low toxicity and overall environmental friendliness. New potentials for improvement in heat transf More

In this study, Bio-based carbon nanotubes (CNTs) have received considerable research attention due to their comparative advantages of high level stability, simplistic use, low toxicity and overall environmental friendliness. New potentials for improvement in heat transfer applications are presented due to their high aspect ratio, high thermal conductivity and special surface area. Phonons have been identified as being responsible for thermal conductivities in carbon nanotubes. Therefore, understanding the mechanism of heat conduction in CNTs involves investigating the difference between the varieties of phonon modes and knowing the kinds of phonon modes that play the dominant role. In this review, a reference to a different number of studies is made and in addition, the role of phonon relaxation rate mainly controlled by boundary scattering and three-phonon Umklapp scattering process was investigated. Results show that the phonon modes are sensitive to a number of nanotube conditions such as: diameter, length, temperature, defects and axial strain. At a low temperature (<100K) the thermal conductivity increases with increasing temperature. A small nanotube size causes phonon quantization which is evident in the thermal conductivity at low temperatures. Manuscript profile

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2 - Preparation and characterization of PEG/Dextran coated superparamagnetic Iron Oxide (Fe3O4) nanoparticles for biomedical applications

Recent progress in nanotechnology and electrochemical methods can be applied to fine control of the size, crystal structure, and surface properties of iron oxide nanoparticles. Here we appliedcathodic electrochemical deposition (CED) as an efficient and effective tactic More

Recent progress in nanotechnology and electrochemical methods can be applied to fine control of the size, crystal structure, and surface properties of iron oxide nanoparticles. Here we appliedcathodic electrochemical deposition (CED) as an efficient and effective tactic for synthesisand double coating of surface of superparamagnetic iron oxide nanoparticles (SPIONs). In first step, bare Fe3O4 nanoparticles were prepared by CED method using a molar ratio of Fe3+:Fe2+ of 2:1. In the next step, the surface of nanoparticles was double coated with dextran (DEX) and polyethylene glycol (PEG) during the CED procedure, and PEG/DEX coated SPIONs were obtained. The prepared NPs were characterized using powderX-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), dynamic light scattering (DLS), vibrating sample magnetometer (VSM) and Field-emission scanning and transmission electron microscopy (FE-SEM and TEM). The XRD results confirmed that both deposited NPs have pure magnetite. FTIR results analysis indicated the existence of two coats (i.e. PEG and DEX) on the surface of depositedparticles. TG analysis exhibited the value of coat on the NPs surface is about 36%. The superparamagnetic properties of both prepared NPs were verified by VSM data, where the PEG/DEX coated NPs showed high magnetization value (Ms=30 emu/g), and negligible coercivity (Ce=0.95 Oe) and remanence (Mr=0.44 emu/g) values. The obtained results confirmed that the prepared Fe3O4 nanoparticles have suitable physico-chemical and magnetic properties for biomedical applications. In final, CED method can be proposed for facile preparation and in situ surface coating of superparamagnetic nanoparticles. Manuscript profile

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3 - NH3 sensors based on novel TiO2/MoS2 nanocomposites: Insights from density functional theory calculations

Density functional theory calculations were performed to investigate the interactions of NH3 molecules with TiO2/MoS2 nanocomposites in order to completely exploit the adsorption properties of these nanocomposites. Given the need to further comprehend the behavior of th More

Density functional theory calculations were performed to investigate the interactions of NH3 molecules with TiO2/MoS2 nanocomposites in order to completely exploit the adsorption properties of these nanocomposites. Given the need to further comprehend the behavior of the NH3 molecules oriented between the TiO2 nanoparticle and MoS2 monolayer, we have geometrically optimized the complex systems consisting of the NH3 molecule positioned at appropriate sites between the nanoparticle and MoS2 monolayer. The structural properties such as bond lengths, bond angles, adsorption energies and Mulliken population analysis and the electronic properties including the density of states and molecular orbitals were also analyzed in detail. The results indicate that the interactions between NH3 molecules and N-doped TiO2 in TiO2-N/MoS2 nanocomposites are stronger than those between gas molecules and undoped TiO2 in TiO2/MoS2 nanocomposites, which reveals that the N doping helps to strengthen the interaction of NH3 molecules with hybrid TiO2/MoS2 nanocomposites. Therefore, the obtained results also present a theoretical basis for the potential application of TiO2/MoS2 nanocomposite as an efficient gas sensor for NH3 molecule in the environment. Manuscript profile

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4 - Synthesis and physicochemical properties of CuMn2O4 nanoparticles; a potential semiconductor for photoelectric devices

CuMn2O4 nanoparticles, a semiconducting materials with tunable functionalities in solid oxide fuel cell, was successfully synthesized via a sol-gel method using its respective metal cations sources i.e. Cu2+ and Mn2+ in an appropriate complexing agent.The vibrational fr More

CuMn2O4 nanoparticles, a semiconducting materials with tunable functionalities in solid oxide fuel cell, was successfully synthesized via a sol-gel method using its respective metal cations sources i.e. Cu2+ and Mn2+ in an appropriate complexing agent.The vibrational frequencies below 1000 cm-1 of the obtained materials confirmed the formation of metal-oxygen (M-O:Cu-O, Mn-O) bond in the sample. The structural analysis of the crystalline phase indicates the formation of a series of sharp peaks with particle size about 39 nm.The cubic crystal structure clearly confirmed the formation of CuMn2O4 with space group Fd3m-copper ions occupied the tetrahedral sites according to (111), (220), (311), and (222) Miller index parameters. Heterogeneous morphology of CuMn2O4 nanoparticles indicated an agglomerated grain structure. The excitation threshold of photoluminescence (PL) indicated that the CuMn2O4 is a medium material in photoluminescence applications. The band gap energy (Eg) equal to 1.4 eV calculated from DR spectra, reavealed that CuMn2O4 can be used as a semiconducting material in photoelectrical devices. Color scale parameters evaluated by colorimetric analysis resulted characteristic values of L*=20.18, a*=2.98 and b*=2.94. Manuscript profile

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5 - The Nitrogen atom effect on structural and magnetic properties of Fullerene C20:A DFT study

The fullerene structures of C20cage and bowl,C20H10 and their N-doped structures as C20cage NH,C20bowl NH, C20H10NH, C20H10N and their isomers are optimized using the MPW1PW91/6-31G level of the theory. Magnetic shielding tensors of 14N and 13C atoms are calculated by t More

The fullerene structures of C20cage and bowl,C20H10 and their N-doped structures as C20cage NH,C20bowl NH, C20H10NH, C20H10N and their isomers are optimized using the MPW1PW91/6-31G level of the theory. Magnetic shielding tensors of 14N and 13C atoms are calculated by the same level of the theory. Results show that doping an N atom on fullerenes affects differently on the chemical shielding of C atoms which are connected to the N atom to be distinguishable experimentally. The maximum chemical shielding of N and N-connected C atoms were shown in the isomer of C20H10NH. It seems that this structure with maximum bond length of C-N is the suitable molecule for additional reactions. Manuscript profile

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6 - Preconcentration of Cu(II)with magnetic nanocomposite sorbentsprior to determination by Flame Atomic Absorption Spectrometer

A simple, highly sensitive, accurate and selective method for determination of trace amounts of Cu2+ in water samples .In this paper, Chitosan was used to encapsulate nano-Fe3O4 and produce a nano-Fe3O4-CHITOSAN sorbent based new sorbent was prepared. This was treated w More

A simple, highly sensitive, accurate and selective method for determination of trace amounts of Cu2+ in water samples .In this paper, Chitosan was used to encapsulate nano-Fe3O4 and produce a nano-Fe3O4-CHITOSAN sorbent based new sorbent was prepared. This was treated with ethylenediamine (ED) in another solvent-free procedure for the formation of a novel nano-Fe3O4-Chitosan-ED.Flame atomic absorption spectrometer was utilized for determination of Cu(II). The analytical features for sorption were found to be 5.2; 4.3 mL min-1 and 55.0 mL for pH, flow rate and sample volume, respectively. HNO3 was used as eluent and maximum preconcentration factor was found to be 200.Elution parameters were also determined as 4 mL min-1; 0.6 mol L-1 and 5.1 mL forflow rate, eluent concentration and eluent volume, respectively.Limit of detection and limit of quantification were found to be 49.6 and 163.7 ng L-1, respectively. Validation of the developed method was performed using certified reference material (TMDA-53.3). The methodology was applied for determination of Cu(II) in natural water samples and satisfactory results were obtained. Manuscript profile

Open Access Article

7 - The thermodynamic parameters of the formation of derivatives of 1-(4-nitrophenyl)-1H-Tetrazole (NPHT) with Boron Nitride nano-cage structure in different temperature conditions, the DFT method

In this study, the response is derived, high-energy material 1-(4-nitrophenyl)-1H-Tetrazole (NPHT) with boron nitridenano-cages in different conditions of temperature, density functional theory methods were studied. for this purpose, the material on both sides were geom More

In this study, the response is derived, high-energy material 1-(4-nitrophenyl)-1H-Tetrazole (NPHT) with boron nitridenano-cages in different conditions of temperature, density functional theory methods were studied. for this purpose, the material on both sides were geometrically optimized, then the calculation of the thermodynamic parameters were performed on all of them. The amount of ΔH, ΔS and ΔG of this reaction at different temperatures for different products together, these parameters in the raw material is obtained. And finally, the best temperatures for the synthesis of derivatives, according to the results of thermodynamic parameters were evaluated. Manuscript profile

Open Access Article

8 - Synthesis and assessment of antibacterial effects of CdSe:Ag nanoparticles produced by chemical precipitation method

Chemical precipitation method was used in order to synthesize CdSe:Ag quantum dots (2-3 nm). Their Physical properties and characteristics were assessed by X-ray diffraction, ultra violet-visible spectrophotometer and TEM (Transmission Electron Microscope) and it was sh More

Chemical precipitation method was used in order to synthesize CdSe:Ag quantum dots (2-3 nm). Their Physical properties and characteristics were assessed by X-ray diffraction, ultra violet-visible spectrophotometer and TEM (Transmission Electron Microscope) and it was shown that the obtained CdSe:Ag quantum dots are cubic with high-quality. Antibacterial effects of CdSe:Ag nanoparticles against some pathogen bacteria were investigated. Pseudomonas aeruginosa, Staphylococcus aureus and Salmonella typhi were used as test microorganisms. Disc bacteriological tests were used in order to assess the effects of CdSe:Ag concentrations 13.4-1.05 mg/ml as antibacterial agent. And the MIC (Minimum Inhibitory Concentration) and MBC (Minimum Bactericial Concentration) of CdSe:Ag nanoparticles which are required to inhibit the growth of these three bacteria is determined by applying Broth Dilution Method. According to the results, by increasing the concentration of CdSe:Ag the inhibiting effect rises. The MIC values to inhibit the bacteria Pseudomonas aeruginosa, Staphylococci aureus and Salmonella typhi are 4.2, 3.35 and 6.7 and the MBC values to do so are 13.4, 8.4 and 13.4, respectively. In conclusion, by increasing the nanoparticle concentration in wells and discs, the growth inhibition and diameter of inhibition zone has also been increased. Manuscript profile

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