Abstract In the present study, synthesis of a novel Mn-Mg binary metal oxide was carried out usin... more Abstract In the present study, synthesis of a novel Mn-Mg binary metal oxide was carried out using facile co-precipitation method for the possible adsorption of copper and zinc from aqueous medium. The prepared adsorbent was characterised to explore the morphology and structure using XRD and SEM. Experimental studies at batch scale were carried out examining the consequence of varying dosage of adsorbent, initial metal concentration, pH of solution and contact time on the adsorptive removal of both copper and zinc. The efficiency was found to increase with increasing dosage of adsorbent (0.1–0.5 g/L) and inversely with initial chromium concentration (10–50 ppm). Adsorption was found increasing with pH shifting from acidic to basic pH range. Adsorption isotherms plotted indicated freundlich model to be fitting better along with pseudo 2nd order kinetics.
Nanotechnology has received much attention in treating contaminated waters. In the present study,... more Nanotechnology has received much attention in treating contaminated waters. In the present study, a facile co-precipitation method was employed to synthesize a novel iron and magnesium based binary metal oxide using a stoichiometrically fixed amount of FeNO3·9H2O and MgNO3·6H2O in a proportion of molar concentration 1:1 and was later evaluated in removing As (III) from contaminated waters. Characterization of the prepared nanomaterial was done using X-ray diffraction (XRD), scanning electron microscopy (SEM), Energy Dispersive X-ray Analysis (EDAX) and ultraviolet–visible spectrophotometry (UV-VIS). Experimental studies on batch scale were carried out, examining the effect of varying initial concentrations of metal, adsorbent dosage, application time and initial pH on removal efficiency. Arsenic removal increased on increasing adsorbent dosage (0.1–1 g/L) but trend reversed on increasing initial arsenic concentration attaining qmax of 263.20 mg/g. Adsorption was quite efficient in p...
3D hierarchical graphitic carbon nanowalls encapsulating cobalt nanoparticles HPC-Co were prepare... more 3D hierarchical graphitic carbon nanowalls encapsulating cobalt nanoparticles HPC-Co were prepared in high yield from solid-state pyrolysis of cobalt 2,2′-bipyridine chloride complex. Annealing of HPC-Co in air gave HPC-CoO, which consists of a mixture of crystallite Co3O4 nanospheres and nanorods bursting out of mesoporous carbon. Both nanocomposites were fully characterized using SEM, TEM, BET, and powder X-ray diffraction. The elemental composition of both nanocomposites examined using SEM elemental mapping and TEM elemental mapping supports the successful doping of nitrogen. The powder X-ray diffraction studies supported the formation of hexagonal cobalt in HPC-Co, and cubic crystalline Co3O4 with cubic cobalt in HPC-CoO. HPC-Co and HPC-CoO can be used as a modified carbon electrode in cyclic voltammetry experiments for the detection of fructose with limit of detection LOD 0.5 mM. However, the single-frequency impedimetric method has a wider dynamic range of 8.0–53.0 mM and a se...
In this research work, SnO2, NiO and SnO2/NiO nanocomposites were synthesized at low temperature ... more In this research work, SnO2, NiO and SnO2/NiO nanocomposites were synthesized at low temperature by modified sol–gel method using ultrasonication. Prepared samples were investigated for their properties employing various characterization techniques. X-ray diffraction (XRD) patterns confirmed the purity and phase of the samples as no secondary phase was detected. The average crystallite size of the nanocomposites was found to decrease from 19.24 to 4.53 nm with the increase in NiO concentration. It was confirmed from SEM micrographs that the material has mesoporous morphology. This mesoporous morphology resulted in the increase of the surface to mass ratio of the material, which in turn increases the specific capacitance of the material. The UV–Visible spectra showed the variation in the band gap of SnO2/NiO at different weight ratio ranging from 3.49 to 3.25 eV on increasing NiO concentration in the samples. These composites with different mass ratio of SnO2 and NiO were also charac...
The adsorption process has been used as an effective technique for the removal of metal ions from... more The adsorption process has been used as an effective technique for the removal of metal ions from aqueous solutions. Groundwater remediation by nanoparticles has received interest in recent years. In the present study, a binary metal oxide of Fe-Cu was prepared and used for the removal of hexavalent chromium from aqueous solution. Batch experiments were performed to investigate the effects of initial Cr (VI) concentration, dose of adsorbent, and pH of solution on the removal efficiency of Cr (VI). The prepared nanostructured Fe-Cu binary oxides were able to reduce the concentration of Cr (VI) in aqueous solution. Binary metal oxides nanoparticle exhibited an outstanding ability to remove Cr (VI) due to high surface area, low particle size, and high inherent activity. The percentage removal efficiency of Cr (VI) increased with nanoparticles doses (0.1 g L−1–2.5 g L−1), whereas it decreased with initial Cr (VI) concentration (1 mg L−1–25 mg L−1) and with pH (3–9). The Freundlich model...
Nanocrystalline cubes of pure and doped LiF material were fabricated. They were doped with Cu, Ag... more Nanocrystalline cubes of pure and doped LiF material were fabricated. They were doped with Cu, Ag, Dy, Tb, and Eu and studied for their PL properties. Shape of the obtained nanocubes was found to be modified by introducing dopants into the host of LiF. The crystallinity was also decreased by increasing the concentration of these dopants (i.e., Eu and Tb). These impurities could induce exothermic peaks at around 250°C in the measured DSC curves. Moreover, incorporating such impurities into the host of LiF was found to enhance intensity of the broad band at 370–550 nm that was observed in the pure one. Extra sharp emissions were also observed in Eu and Tb doped samples. These results showed that the active color centers created in pure LiF nanocubes can be enriched/enhanced by these impurities, mainly Eu and Tb. This implies that these nanocubes might be useful in the development of optical devices and advanced color center laser.
Abstract This paper presents a practical, reusable and stable photocatalyst, CuFe0.9Ti0.1O2/GO, f... more Abstract This paper presents a practical, reusable and stable photocatalyst, CuFe0.9Ti0.1O2/GO, for the degradation of toxic organic dyes in water. The photocatalyst is visible light-driven, and magnetically separable which makes the photocatalyst unique and novel. The photocatalyst was successfully synthesized by a sonochemical method and post-treated with microwaves. Characterization techniques like XRD, FTIR, SEM, DRS, Raman, and VSM were used to ascertain its phase and composition, morphology, bandgap, and magnetic properties. X-ray diffraction (XRD) confirmed the phase and composition of these materials. Further, it has been observed from the characteristic peaks of XRD that Ti+4 ions have been effectively incorporated into parent material CuFeO2 with little variations due to close ionic radii of Fe+3 and Ti+4 ions. Diffusive Reflectance Spectroscopy (DRS) was used to observe the absorption spectra, and the energy bandgap was calculated using Kubelka – Munk (KM) model. The indirect energy band gap was found to be 3.02, 2.72, 2.88 eV for pure, Ti-doped and GO based CuFeO2, respectively. Pure CuFeO2 delafossite system shows ferromagnetic behavior, which is due to the magnetic spins present in the system. Ti-doped and GO based samples also show ferromagnetic behavior but with some lower saturation magnetization values. The saturation magnetizations of pure, Ti-doped and GO based CuFeO2 samples were measured to be 28.29, 17.43, 15.36 emu g−1 at 5 K and 25.01, 14.76, 12.48 emu g−1 at 300 K respectively. The material's photocatalytic activity was defined by observing the UV–visible absorption spectra of MB dye with exposure to light. The results show that the intensity of the absorption peaks of MB decreases with the increase in the exposure time of the solution in visible light, indicating the complete degradation of MB dye within 36 min. The reaction rate constant k for the photocatalyst was found to be 0.168 min−1 proving the photocatalyst to be effective and practical for potential applications.
388 Int. J. Nanoparticles, Vol. 2, Nos. 1/2/3/4/5/6, 2009 ... Synthesis of zinc ferrite nanoparti... more 388 Int. J. Nanoparticles, Vol. 2, Nos. 1/2/3/4/5/6, 2009 ... Synthesis of zinc ferrite nanoparticles by sol-gel method and their characterisation ... Ameer Azam*, Mohammad Chaman and Alim H. Naqvi ... Department of Applied Physics, ZH College of Engineering & Technology, ...
Http Dx Doi Org 10 1080 09500839 2012 739785, Jan 23, 2013
ABSTRACT The study of porous silicon (PS) structures is important for the fundamental understandi... more ABSTRACT The study of porous silicon (PS) structures is important for the fundamental understanding of these nanostructures and their potential applications. Here, we present a qualitative analysis of the response kinetics of a capacitive PS sensor to different organic vapors. The large surface area of PS obtained by electrochemically etching a silicon wafer has been exploited to study its sensing behavior and to explore the possibilities of a simple and cost-effective sensor for selective gas analysis. The results provide some interesting observations, which may be helpful in understanding the character of PS-based sensors.
Production of plant growth promoting substances by rhizosphere microorganisms. SAZ Mahmoud, EM Ra... more Production of plant growth promoting substances by rhizosphere microorganisms. SAZ Mahmoud, EM Ramadan, FM Thabet, T Khater Microbiological Research 139:44, 227-232, 1984. Different microorganisms ...
Zinc oxide (ZnO) nanoparticles (< 20 nm) were synthesi... more Zinc oxide (ZnO) nanoparticles (< 20 nm) were synthesised by sol-gel method and characterised by X-ray diffraction (XRD). Extensive use of ZnO in sunscreens and cosmetics, and their reported photoclastogenicity has prompted us to investigate its genotoxic potential. We have assessed the ZnO-induced DNA damage, intracellular ROS generation and change in mitochondrial membrane potential (ΔΨm), employing alkaline single cell gel electrophoresis (comet assay), flow cytometry and spectrofluorometric analysis. Significant ...
Abstract In the present study, synthesis of a novel Mn-Mg binary metal oxide was carried out usin... more Abstract In the present study, synthesis of a novel Mn-Mg binary metal oxide was carried out using facile co-precipitation method for the possible adsorption of copper and zinc from aqueous medium. The prepared adsorbent was characterised to explore the morphology and structure using XRD and SEM. Experimental studies at batch scale were carried out examining the consequence of varying dosage of adsorbent, initial metal concentration, pH of solution and contact time on the adsorptive removal of both copper and zinc. The efficiency was found to increase with increasing dosage of adsorbent (0.1–0.5 g/L) and inversely with initial chromium concentration (10–50 ppm). Adsorption was found increasing with pH shifting from acidic to basic pH range. Adsorption isotherms plotted indicated freundlich model to be fitting better along with pseudo 2nd order kinetics.
Nanotechnology has received much attention in treating contaminated waters. In the present study,... more Nanotechnology has received much attention in treating contaminated waters. In the present study, a facile co-precipitation method was employed to synthesize a novel iron and magnesium based binary metal oxide using a stoichiometrically fixed amount of FeNO3·9H2O and MgNO3·6H2O in a proportion of molar concentration 1:1 and was later evaluated in removing As (III) from contaminated waters. Characterization of the prepared nanomaterial was done using X-ray diffraction (XRD), scanning electron microscopy (SEM), Energy Dispersive X-ray Analysis (EDAX) and ultraviolet–visible spectrophotometry (UV-VIS). Experimental studies on batch scale were carried out, examining the effect of varying initial concentrations of metal, adsorbent dosage, application time and initial pH on removal efficiency. Arsenic removal increased on increasing adsorbent dosage (0.1–1 g/L) but trend reversed on increasing initial arsenic concentration attaining qmax of 263.20 mg/g. Adsorption was quite efficient in p...
3D hierarchical graphitic carbon nanowalls encapsulating cobalt nanoparticles HPC-Co were prepare... more 3D hierarchical graphitic carbon nanowalls encapsulating cobalt nanoparticles HPC-Co were prepared in high yield from solid-state pyrolysis of cobalt 2,2′-bipyridine chloride complex. Annealing of HPC-Co in air gave HPC-CoO, which consists of a mixture of crystallite Co3O4 nanospheres and nanorods bursting out of mesoporous carbon. Both nanocomposites were fully characterized using SEM, TEM, BET, and powder X-ray diffraction. The elemental composition of both nanocomposites examined using SEM elemental mapping and TEM elemental mapping supports the successful doping of nitrogen. The powder X-ray diffraction studies supported the formation of hexagonal cobalt in HPC-Co, and cubic crystalline Co3O4 with cubic cobalt in HPC-CoO. HPC-Co and HPC-CoO can be used as a modified carbon electrode in cyclic voltammetry experiments for the detection of fructose with limit of detection LOD 0.5 mM. However, the single-frequency impedimetric method has a wider dynamic range of 8.0–53.0 mM and a se...
In this research work, SnO2, NiO and SnO2/NiO nanocomposites were synthesized at low temperature ... more In this research work, SnO2, NiO and SnO2/NiO nanocomposites were synthesized at low temperature by modified sol–gel method using ultrasonication. Prepared samples were investigated for their properties employing various characterization techniques. X-ray diffraction (XRD) patterns confirmed the purity and phase of the samples as no secondary phase was detected. The average crystallite size of the nanocomposites was found to decrease from 19.24 to 4.53 nm with the increase in NiO concentration. It was confirmed from SEM micrographs that the material has mesoporous morphology. This mesoporous morphology resulted in the increase of the surface to mass ratio of the material, which in turn increases the specific capacitance of the material. The UV–Visible spectra showed the variation in the band gap of SnO2/NiO at different weight ratio ranging from 3.49 to 3.25 eV on increasing NiO concentration in the samples. These composites with different mass ratio of SnO2 and NiO were also charac...
The adsorption process has been used as an effective technique for the removal of metal ions from... more The adsorption process has been used as an effective technique for the removal of metal ions from aqueous solutions. Groundwater remediation by nanoparticles has received interest in recent years. In the present study, a binary metal oxide of Fe-Cu was prepared and used for the removal of hexavalent chromium from aqueous solution. Batch experiments were performed to investigate the effects of initial Cr (VI) concentration, dose of adsorbent, and pH of solution on the removal efficiency of Cr (VI). The prepared nanostructured Fe-Cu binary oxides were able to reduce the concentration of Cr (VI) in aqueous solution. Binary metal oxides nanoparticle exhibited an outstanding ability to remove Cr (VI) due to high surface area, low particle size, and high inherent activity. The percentage removal efficiency of Cr (VI) increased with nanoparticles doses (0.1 g L−1–2.5 g L−1), whereas it decreased with initial Cr (VI) concentration (1 mg L−1–25 mg L−1) and with pH (3–9). The Freundlich model...
Nanocrystalline cubes of pure and doped LiF material were fabricated. They were doped with Cu, Ag... more Nanocrystalline cubes of pure and doped LiF material were fabricated. They were doped with Cu, Ag, Dy, Tb, and Eu and studied for their PL properties. Shape of the obtained nanocubes was found to be modified by introducing dopants into the host of LiF. The crystallinity was also decreased by increasing the concentration of these dopants (i.e., Eu and Tb). These impurities could induce exothermic peaks at around 250°C in the measured DSC curves. Moreover, incorporating such impurities into the host of LiF was found to enhance intensity of the broad band at 370–550 nm that was observed in the pure one. Extra sharp emissions were also observed in Eu and Tb doped samples. These results showed that the active color centers created in pure LiF nanocubes can be enriched/enhanced by these impurities, mainly Eu and Tb. This implies that these nanocubes might be useful in the development of optical devices and advanced color center laser.
Abstract This paper presents a practical, reusable and stable photocatalyst, CuFe0.9Ti0.1O2/GO, f... more Abstract This paper presents a practical, reusable and stable photocatalyst, CuFe0.9Ti0.1O2/GO, for the degradation of toxic organic dyes in water. The photocatalyst is visible light-driven, and magnetically separable which makes the photocatalyst unique and novel. The photocatalyst was successfully synthesized by a sonochemical method and post-treated with microwaves. Characterization techniques like XRD, FTIR, SEM, DRS, Raman, and VSM were used to ascertain its phase and composition, morphology, bandgap, and magnetic properties. X-ray diffraction (XRD) confirmed the phase and composition of these materials. Further, it has been observed from the characteristic peaks of XRD that Ti+4 ions have been effectively incorporated into parent material CuFeO2 with little variations due to close ionic radii of Fe+3 and Ti+4 ions. Diffusive Reflectance Spectroscopy (DRS) was used to observe the absorption spectra, and the energy bandgap was calculated using Kubelka – Munk (KM) model. The indirect energy band gap was found to be 3.02, 2.72, 2.88 eV for pure, Ti-doped and GO based CuFeO2, respectively. Pure CuFeO2 delafossite system shows ferromagnetic behavior, which is due to the magnetic spins present in the system. Ti-doped and GO based samples also show ferromagnetic behavior but with some lower saturation magnetization values. The saturation magnetizations of pure, Ti-doped and GO based CuFeO2 samples were measured to be 28.29, 17.43, 15.36 emu g−1 at 5 K and 25.01, 14.76, 12.48 emu g−1 at 300 K respectively. The material's photocatalytic activity was defined by observing the UV–visible absorption spectra of MB dye with exposure to light. The results show that the intensity of the absorption peaks of MB decreases with the increase in the exposure time of the solution in visible light, indicating the complete degradation of MB dye within 36 min. The reaction rate constant k for the photocatalyst was found to be 0.168 min−1 proving the photocatalyst to be effective and practical for potential applications.
388 Int. J. Nanoparticles, Vol. 2, Nos. 1/2/3/4/5/6, 2009 ... Synthesis of zinc ferrite nanoparti... more 388 Int. J. Nanoparticles, Vol. 2, Nos. 1/2/3/4/5/6, 2009 ... Synthesis of zinc ferrite nanoparticles by sol-gel method and their characterisation ... Ameer Azam*, Mohammad Chaman and Alim H. Naqvi ... Department of Applied Physics, ZH College of Engineering & Technology, ...
Http Dx Doi Org 10 1080 09500839 2012 739785, Jan 23, 2013
ABSTRACT The study of porous silicon (PS) structures is important for the fundamental understandi... more ABSTRACT The study of porous silicon (PS) structures is important for the fundamental understanding of these nanostructures and their potential applications. Here, we present a qualitative analysis of the response kinetics of a capacitive PS sensor to different organic vapors. The large surface area of PS obtained by electrochemically etching a silicon wafer has been exploited to study its sensing behavior and to explore the possibilities of a simple and cost-effective sensor for selective gas analysis. The results provide some interesting observations, which may be helpful in understanding the character of PS-based sensors.
Production of plant growth promoting substances by rhizosphere microorganisms. SAZ Mahmoud, EM Ra... more Production of plant growth promoting substances by rhizosphere microorganisms. SAZ Mahmoud, EM Ramadan, FM Thabet, T Khater Microbiological Research 139:44, 227-232, 1984. Different microorganisms ...
Zinc oxide (ZnO) nanoparticles (< 20 nm) were synthesi... more Zinc oxide (ZnO) nanoparticles (< 20 nm) were synthesised by sol-gel method and characterised by X-ray diffraction (XRD). Extensive use of ZnO in sunscreens and cosmetics, and their reported photoclastogenicity has prompted us to investigate its genotoxic potential. We have assessed the ZnO-induced DNA damage, intracellular ROS generation and change in mitochondrial membrane potential (ΔΨm), employing alkaline single cell gel electrophoresis (comet assay), flow cytometry and spectrofluorometric analysis. Significant ...
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