Journal of Sol-Gel Science and Technology, Jul 19, 2018
Visible light active titanium dioxide (TiO 2) nano particles with high photocatalytic efficiency ... more Visible light active titanium dioxide (TiO 2) nano particles with high photocatalytic efficiency were prepared by sol gel method from titanium isopropoxide precursor by carefully controlling the synthesis conditions such as solvent and pH. Solvents used in this study are isopropanol, ethanol and methanol. The pH values considered are 1, 4 and 8. The products obtained were characterized using X-ray diffraction, UV-Visible spectroscopy, Fourier transform infrared (FTIR) spectroscopy, photoluminescence (PL) spectroscopy, scanning electron microscopy (SEM) and high-resolution transmission electron microscopy (HRTEM). TiO 2 synthesized using methanol as a solvent at pH 1 showed a significant decrease in band gap (2.93 eV) when compared to that of anatase (3.2 eV) and rutile (3.0 eV). Visible light photocatalytic activity of the material with lowest band gap was determined by studying the photodegradation of methylene blue (MB) dye. The material showed a photodegradation efficiency of 84% after 180 minutes which is generally difficult to attain without doping or surface modification. We could achieve a high photocatalytic efficiency by band gap engineering which was done by changing the synthesis conditions.
International Journal of Environmental Science and Technology, 2020
The use of photocatalysis in wastewater treatment using low cost photocatalyst plays a vital role... more The use of photocatalysis in wastewater treatment using low cost photocatalyst plays a vital role in thwarting the enigma of water pollution. In this work, we report synthesis of metal-and non-metal-doped zinc oxide (ZnO) nanostructures via solid state, solvent and surfactant-free microwave-assisted thermal decomposition method. HRTEM images confirm the formation of highly crystalline nanorod morphology in the case of sodium-doped ZnO. The photocatalytic activity of the synthesized samples initially assessed by the degradation of methylene blue under visible light illumination suggests that SZO-3 (15wt% Na-doped) with admirable degradation rate (95% in 180 min with apparent rate constant of 1.69 × 10-2 min −1) and tenacious photostability envisages its potential applications in water treatment processes. The coalescence of ultrasound, visible light and catalyst resulted in augmented degradation (99.5%) in 60 min.
Visible light active titanium dioxide (TiO 2) nano particles with high photocatalytic efficiency ... more Visible light active titanium dioxide (TiO 2) nano particles with high photocatalytic efficiency were prepared by sol gel method from titanium isopropoxide precursor by carefully controlling the synthesis conditions such as solvent and pH. Solvents used in this study are isopropanol, ethanol and methanol. The pH values considered are 1, 4 and 8. The products obtained were characterized using X-ray diffraction, UV-Visible spectroscopy, Fourier transform infrared (FTIR) spectroscopy, photoluminescence (PL) spectroscopy, scanning electron microscopy (SEM) and high-resolution transmission electron microscopy (HRTEM). TiO 2 synthesized using methanol as a solvent at pH 1 showed a significant decrease in band gap (2.93 eV) when compared to that of anatase (3.2 eV) and rutile (3.0 eV). Visible light photocatalytic activity of the material with lowest band gap was determined by studying the photodegradation of methylene blue (MB) dye. The material showed a photodegradation efficiency of 84% after 180 minutes which is generally difficult to attain without doping or surface modification. We could achieve a high photocatalytic efficiency by band gap engineering which was done by changing the synthesis conditions.
Journal of Materials Science: Materials in Electronics, 2020
Green chemistry is considered as an effective alternative for the conventional chemistry in the p... more Green chemistry is considered as an effective alternative for the conventional chemistry in the perspective of environmental sustainability. The principles of green chemistry can be applied to the field of nanotechnology especially for the synthesis of nanomaterials. In the current work, we have demonstrated an ecofriendly and inexpensive plant-mediated green method for the synthesis of visible light active titanium dioxide (TiO 2) nanoparticles with exposed highenergy {001} facets using the leaf extract of Chromolaena Odorata. The synthesized nanoparticles were analyzed using UV-Vis spectroscopy, X-ray diffraction (XRD), FTIR spectroscopy, Photoluminescence (PL) spectroscopy, X-ray photoelectron spectroscopy (XPS), and high-resolution transmission electron spectroscopy (HRTEM). Studies showed that phytochemicals present in the plant extract act as both reducing agent and capping agent in the synthesis. The photocatalytic activity of the synthesized materials was determined by analyzing the photodegradation of four different dyes such as methylene blue, fuchsine, crystal violet, and rhodamine 6G. All the dyes showed more than 85% degradation in 180 min. When compared with the chemically synthesized materials, the green synthesized TiO 2 showed a better photocatalytic activity. The superior photocatalytic performance of the sample is mainly attributed to the presence of defects and coexistence of {001} and {101} facets. The method described here leads to a new route for the synthesis of visible light active TiO 2 nanoparticles with exposed {001} facets.
Journal of Sol-Gel Science and Technology, Jul 19, 2018
Visible light active titanium dioxide (TiO 2) nano particles with high photocatalytic efficiency ... more Visible light active titanium dioxide (TiO 2) nano particles with high photocatalytic efficiency were prepared by sol gel method from titanium isopropoxide precursor by carefully controlling the synthesis conditions such as solvent and pH. Solvents used in this study are isopropanol, ethanol and methanol. The pH values considered are 1, 4 and 8. The products obtained were characterized using X-ray diffraction, UV-Visible spectroscopy, Fourier transform infrared (FTIR) spectroscopy, photoluminescence (PL) spectroscopy, scanning electron microscopy (SEM) and high-resolution transmission electron microscopy (HRTEM). TiO 2 synthesized using methanol as a solvent at pH 1 showed a significant decrease in band gap (2.93 eV) when compared to that of anatase (3.2 eV) and rutile (3.0 eV). Visible light photocatalytic activity of the material with lowest band gap was determined by studying the photodegradation of methylene blue (MB) dye. The material showed a photodegradation efficiency of 84% after 180 minutes which is generally difficult to attain without doping or surface modification. We could achieve a high photocatalytic efficiency by band gap engineering which was done by changing the synthesis conditions.
International Journal of Environmental Science and Technology, 2020
The use of photocatalysis in wastewater treatment using low cost photocatalyst plays a vital role... more The use of photocatalysis in wastewater treatment using low cost photocatalyst plays a vital role in thwarting the enigma of water pollution. In this work, we report synthesis of metal-and non-metal-doped zinc oxide (ZnO) nanostructures via solid state, solvent and surfactant-free microwave-assisted thermal decomposition method. HRTEM images confirm the formation of highly crystalline nanorod morphology in the case of sodium-doped ZnO. The photocatalytic activity of the synthesized samples initially assessed by the degradation of methylene blue under visible light illumination suggests that SZO-3 (15wt% Na-doped) with admirable degradation rate (95% in 180 min with apparent rate constant of 1.69 × 10-2 min −1) and tenacious photostability envisages its potential applications in water treatment processes. The coalescence of ultrasound, visible light and catalyst resulted in augmented degradation (99.5%) in 60 min.
Visible light active titanium dioxide (TiO 2) nano particles with high photocatalytic efficiency ... more Visible light active titanium dioxide (TiO 2) nano particles with high photocatalytic efficiency were prepared by sol gel method from titanium isopropoxide precursor by carefully controlling the synthesis conditions such as solvent and pH. Solvents used in this study are isopropanol, ethanol and methanol. The pH values considered are 1, 4 and 8. The products obtained were characterized using X-ray diffraction, UV-Visible spectroscopy, Fourier transform infrared (FTIR) spectroscopy, photoluminescence (PL) spectroscopy, scanning electron microscopy (SEM) and high-resolution transmission electron microscopy (HRTEM). TiO 2 synthesized using methanol as a solvent at pH 1 showed a significant decrease in band gap (2.93 eV) when compared to that of anatase (3.2 eV) and rutile (3.0 eV). Visible light photocatalytic activity of the material with lowest band gap was determined by studying the photodegradation of methylene blue (MB) dye. The material showed a photodegradation efficiency of 84% after 180 minutes which is generally difficult to attain without doping or surface modification. We could achieve a high photocatalytic efficiency by band gap engineering which was done by changing the synthesis conditions.
Journal of Materials Science: Materials in Electronics, 2020
Green chemistry is considered as an effective alternative for the conventional chemistry in the p... more Green chemistry is considered as an effective alternative for the conventional chemistry in the perspective of environmental sustainability. The principles of green chemistry can be applied to the field of nanotechnology especially for the synthesis of nanomaterials. In the current work, we have demonstrated an ecofriendly and inexpensive plant-mediated green method for the synthesis of visible light active titanium dioxide (TiO 2) nanoparticles with exposed highenergy {001} facets using the leaf extract of Chromolaena Odorata. The synthesized nanoparticles were analyzed using UV-Vis spectroscopy, X-ray diffraction (XRD), FTIR spectroscopy, Photoluminescence (PL) spectroscopy, X-ray photoelectron spectroscopy (XPS), and high-resolution transmission electron spectroscopy (HRTEM). Studies showed that phytochemicals present in the plant extract act as both reducing agent and capping agent in the synthesis. The photocatalytic activity of the synthesized materials was determined by analyzing the photodegradation of four different dyes such as methylene blue, fuchsine, crystal violet, and rhodamine 6G. All the dyes showed more than 85% degradation in 180 min. When compared with the chemically synthesized materials, the green synthesized TiO 2 showed a better photocatalytic activity. The superior photocatalytic performance of the sample is mainly attributed to the presence of defects and coexistence of {001} and {101} facets. The method described here leads to a new route for the synthesis of visible light active TiO 2 nanoparticles with exposed {001} facets.
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