Pd-MoO3/SiO2 catalyst has been prepared using the method of incipient wetness impregnation. The photo absorbing behaviors and chemisorbing properties of the catalyst have been characterized by UV-vis spectra and TPD-M...Pd-MoO3/SiO2 catalyst has been prepared using the method of incipient wetness impregnation. The photo absorbing behaviors and chemisorbing properties of the catalyst have been characterized by UV-vis spectra and TPD-MS experiments. The results indicated that metal Pd loaded on MoOa/SiO2 has a significant effect on the photo absorbing performance of MoOa/SiO2, and an obvious blue shift of the absorption edge is produced. Under UV irradiation, the chemisorption state of CO2 undergoes decomposing process to form CO at 481 K, and a two-site adsorption state of ethane can be formed at around 496 K. Photo-oxidation of ethane using carbon dioxide can mainly produce propanal, ethanol and acetaldehyde in the temperature range of 353-423 K. The presence of metal Pd improves the catalytic activity remarkably.展开更多
In the present article, an easy synthetic strategy of a novel composite photo-catalyst comprising of amino-functionalized reduced graphene oxide and Cu2O has been proposed. Role of this composite catalyst in photo red...In the present article, an easy synthetic strategy of a novel composite photo-catalyst comprising of amino-functionalized reduced graphene oxide and Cu2O has been proposed. Role of this composite catalyst in photo reduction of CO2 has been analyzed and it is shown that both amino groups and reduced grapheme oxide, participate in enhancing quantum yield of the photo reduction process.展开更多
Safe, sustainable, and green production of hydro gen peroxide is an exciting proposition due to the role of hydrogen peroxide as a green oxidant and energy carrier for fuel cells. The current work reports the developm...Safe, sustainable, and green production of hydro gen peroxide is an exciting proposition due to the role of hydrogen peroxide as a green oxidant and energy carrier for fuel cells. The current work reports the development of carbon dot-impregnated waterborne hyperbranched polyurethane as a heterogeneous photo-catalyst for solar-driven production of hydrogen peroxide. The results reveal that the carbon dots possess a suitable band-gap of 2.98 eV,which facilitates effective splitting of both water and ethanol under solar irradiation. Inclusion of the carbon dots within the eco-friendly polymeric material ensures their catalytic activity and also provides a facile route for easy catalyst separation, especially from a solubilizing medium.The overall process was performed in accordance with the principles of green chemistry using bio-based precursorsand aqueous medium. This work highlights the potential of carbon dots as an effective photo-catalyst.展开更多
Sea urchin-like cuprous oxide with hollow glass microsphere as core was prepared using sodium sulfite as the reducing agent and sodium acetate-acetic acid as buffer solution in copper sulfate solution. Methyl orange w...Sea urchin-like cuprous oxide with hollow glass microsphere as core was prepared using sodium sulfite as the reducing agent and sodium acetate-acetic acid as buffer solution in copper sulfate solution. Methyl orange was selected as degradation target for photocatalytic experiments. The photocatalytic activities were investigated by visible spectro- photometer. Photocatalytic kinetics parameters were studied by the Langmuir-Hinshelwood model and Arrhenius formula. It was observed that the sea urchin-like morphology dramatically improved the photocatalytic activity of cuprous oxide. The photo-degradation belongs to the first-order reaction and the maximum degradation rate could reach 94.37%. The activation energy and pre-exponential factor are 41.18 KJ·mol-1 and 1.07 × 106, respectively. After seven times recycling, the sample still showed high photo-catalytic efficiency and stability.展开更多
A microwave-assisted heating approach was developed to fabricate SnO2·TiO2 nano-composite in an aqueoas sohaion of sulphuric acid in the presence of SnO2 nano-powder and titanium sulfate. Powder X-ray diffraction...A microwave-assisted heating approach was developed to fabricate SnO2·TiO2 nano-composite in an aqueoas sohaion of sulphuric acid in the presence of SnO2 nano-powder and titanium sulfate. Powder X-ray diffraction （ XRD ） pattern indicates that the products were a composite with both of anatase-type TiO2 and tetrahedrul SnO2. The prnducts were also characterized by transmission electron microscolry （ TEM ）, photoluminescence （PL） spectra. The photo-catalytic property of the as-prepared sample has ulso been studied. The result indicates that the as-prepared sample is a good photo-catadyst.展开更多
In this paper, an experimental investigation on the effect of parameters namely concentration, solar radiation intensity and exposure time on the photo oxidation of pollutants in secondary treated municipal wastewater...In this paper, an experimental investigation on the effect of parameters namely concentration, solar radiation intensity and exposure time on the photo oxidation of pollutants in secondary treated municipal wastewater has been presented. TiO2 was used as the photo catalyst and the experiments were carried out in the month of February 2012 in Oman. The reactor was a glass tube constructed with the provision of adding a reflector. The results showed that photo catalytic treatment is very effective for dilute solutions and the presence of reflector enhances the photo degradation. The reduction in Chemical Oxygen Demand (COD) obtained at the experimental conditions of 0.007 m3/hr flow rate, 15°?inclination angle and 1 g·L-1?TiO2 dosage was 18%. The presence of the reflector increased the degradation to 25% at the above experimental conditions.展开更多
基金This work was supported by the National Key Basic Research Project of China (No. 2001CCA03600).
文摘Pd-MoO3/SiO2 catalyst has been prepared using the method of incipient wetness impregnation. The photo absorbing behaviors and chemisorbing properties of the catalyst have been characterized by UV-vis spectra and TPD-MS experiments. The results indicated that metal Pd loaded on MoOa/SiO2 has a significant effect on the photo absorbing performance of MoOa/SiO2, and an obvious blue shift of the absorption edge is produced. Under UV irradiation, the chemisorption state of CO2 undergoes decomposing process to form CO at 481 K, and a two-site adsorption state of ethane can be formed at around 496 K. Photo-oxidation of ethane using carbon dioxide can mainly produce propanal, ethanol and acetaldehyde in the temperature range of 353-423 K. The presence of metal Pd improves the catalytic activity remarkably.
文摘In the present article, an easy synthetic strategy of a novel composite photo-catalyst comprising of amino-functionalized reduced graphene oxide and Cu2O has been proposed. Role of this composite catalyst in photo reduction of CO2 has been analyzed and it is shown that both amino groups and reduced grapheme oxide, participate in enhancing quantum yield of the photo reduction process.
基金DBT(Grant No.BT/235/NE/TBP/2011 Dated April 30,2012),India,for financial support
文摘Safe, sustainable, and green production of hydro gen peroxide is an exciting proposition due to the role of hydrogen peroxide as a green oxidant and energy carrier for fuel cells. The current work reports the development of carbon dot-impregnated waterborne hyperbranched polyurethane as a heterogeneous photo-catalyst for solar-driven production of hydrogen peroxide. The results reveal that the carbon dots possess a suitable band-gap of 2.98 eV,which facilitates effective splitting of both water and ethanol under solar irradiation. Inclusion of the carbon dots within the eco-friendly polymeric material ensures their catalytic activity and also provides a facile route for easy catalyst separation, especially from a solubilizing medium.The overall process was performed in accordance with the principles of green chemistry using bio-based precursorsand aqueous medium. This work highlights the potential of carbon dots as an effective photo-catalyst.
文摘Sea urchin-like cuprous oxide with hollow glass microsphere as core was prepared using sodium sulfite as the reducing agent and sodium acetate-acetic acid as buffer solution in copper sulfate solution. Methyl orange was selected as degradation target for photocatalytic experiments. The photocatalytic activities were investigated by visible spectro- photometer. Photocatalytic kinetics parameters were studied by the Langmuir-Hinshelwood model and Arrhenius formula. It was observed that the sea urchin-like morphology dramatically improved the photocatalytic activity of cuprous oxide. The photo-degradation belongs to the first-order reaction and the maximum degradation rate could reach 94.37%. The activation energy and pre-exponential factor are 41.18 KJ·mol-1 and 1.07 × 106, respectively. After seven times recycling, the sample still showed high photo-catalytic efficiency and stability.
文摘A microwave-assisted heating approach was developed to fabricate SnO2·TiO2 nano-composite in an aqueoas sohaion of sulphuric acid in the presence of SnO2 nano-powder and titanium sulfate. Powder X-ray diffraction （ XRD ） pattern indicates that the products were a composite with both of anatase-type TiO2 and tetrahedrul SnO2. The prnducts were also characterized by transmission electron microscolry （ TEM ）, photoluminescence （PL） spectra. The photo-catalytic property of the as-prepared sample has ulso been studied. The result indicates that the as-prepared sample is a good photo-catadyst.
文摘In this paper, an experimental investigation on the effect of parameters namely concentration, solar radiation intensity and exposure time on the photo oxidation of pollutants in secondary treated municipal wastewater has been presented. TiO2 was used as the photo catalyst and the experiments were carried out in the month of February 2012 in Oman. The reactor was a glass tube constructed with the provision of adding a reflector. The results showed that photo catalytic treatment is very effective for dilute solutions and the presence of reflector enhances the photo degradation. The reduction in Chemical Oxygen Demand (COD) obtained at the experimental conditions of 0.007 m3/hr flow rate, 15°?inclination angle and 1 g·L-1?TiO2 dosage was 18%. The presence of the reflector increased the degradation to 25% at the above experimental conditions.
基金This work was supported by the National Natural Science Foundation of China （ No.：60671010, 20775045 ） and Natural Science Foundation of Shandong Province （Y2006B29）. The authors wish to thank Prof. D.R. Chen and Mr. H.F. Shao for the help in measurements of XRD and XPS, respectively.
