A series of phosphorus-modified titanium dioxide samples with varying P/Ti atomic ratio were conveniently prepared via a conventional solgel route. The effects of phosphorus content and calcination temperature on the ...A series of phosphorus-modified titanium dioxide samples with varying P/Ti atomic ratio were conveniently prepared via a conventional solgel route. The effects of phosphorus content and calcination temperature on the crystalline structure, grain growth, surface area, and the photocatalytic activity of P-modified TiO2 were investigated. The XRD results showed that P species slow down the particle growth of anatase and increase the anatase-to-rutile phase transformation temperature to more than 900°C. Kinetic studies on the P-modified TiO2 to degraded 4-chlorophenol had found that the TP5500 prepared by adopting a P/Ti atomic ratio equal to 0.05 and calcined at 500°C had an apparent rate constant equal to 0.0075 min 1, which is superior to the performance of a commercial photocatalyst Degussa P25 Kapp = 0.0045 min 1 and of unmodified TiO2 (TP0500) Kapp = 0.0022 min 1. From HPLC analyses, various hydroxylated intermediates formed during oxidation had been identified, including hydroquinone (HQ), benzoquinone (BQ) and (4CC) 4-chlorocatechol as main products. Phytotoxicity was assessed before and after irradiation against seed germination of tomato (Lycopersicon esculentum) whereas acute toxicity was assessed by using Folsomia candida as the test organism. Intermediates products were all less toxic than 4-chlorophenol and a significant removal of the overall toxicity was accomplished展开更多
Recently,self-powered ultraviolet photodetectors(UV PDs)based on SnO_(2)have gained increasing interest due to its feature of working continuously without the need for external power sources.Nevertheless,the productio...Recently,self-powered ultraviolet photodetectors(UV PDs)based on SnO_(2)have gained increasing interest due to its feature of working continuously without the need for external power sources.Nevertheless,the production of the majority of these existing UV PDs necessitates additional manufacturing stages or intricate processes.In this work,we present a facile,cost-effective approach for the fabrication of a self-powered UV PD based on p-Si/n-SnO_(2)junction.The self-powered device was achieved simply by integrating a p-Si substrate with a n-type SnO_(2)microbelt,which was synthesized via the chemical vapor deposition(CVD)method.The high-quality feature,coupled with the belt-like shape of the SnO_(2)microbelt enables the favorable contact between the n-type SnO_(2)and p-type silicon.The built-in electric field created at the interface endows the self-powered performance of the device.The p-Si/n-SnO_(2)junction photodetector demonstrated a high responsivity(0.12 mA/W),high light/dark current ratio(>103),and rapid response speed at zero bias.This method offers a practical way to develop cost-effective and high-performance self-powered UV PDs.展开更多
The steel industry produces many byproducts, requiring extensive land for storage and causing significant environmental contamination. Industrial effluents discharged into water bodies negatively impact both aquatic e...The steel industry produces many byproducts, requiring extensive land for storage and causing significant environmental contamination. Industrial effluents discharged into water bodies negatively impact both aquatic ecosystems and human health. To solve this problem, this study synthesized a composite of titanium dioxide (TiO2) and steel slag nanocomposites (SSNC) at a 1:2 mass ratio to create a robust photocatalyst for the treatment of synthetic wastewater. The efficacy of this catalyst in degrading various dye pollutants, including methylene blue (MB), was tested under simulated solar light conditions. Comprehensive analyses were conducted to assess the physical and chemical characteristics, crystalline structure, energy gap, and point of zero charge of the composite. The TiO2-SSNC composite catalyst exhibited excellent stability, with a point of zero charge at 8.342 and an energy gap of 2.4 eV. The degradation process conformed to pseudo-first-order kinetics. Optimization of operational parameters was achieved through the response surface methodology. Reusability tests demonstrated that the TiO2-SSNC composite catalyst effectively degraded up to 93.41% of MB in the suspended mode and 92.03% in the coated mode after five cycles. Additionally, the degradation efficiencies for various dyes were significant, highlighting the potential of the composite for broad applications in industrial wastewater treatment. This study also explored the degradation mechanisms and identified byproducts, establishing a pathway for contaminant breakdown. The cost-benefit analysis revealed a total cost of 0.842 8 USD per cubic meter for each treatment activity, indicating low operational and production costs. These findings underscore the promise of the TiO2-SSNC composite as a cost-effective and efficient alternative for wastewater purification.展开更多
文摘A series of phosphorus-modified titanium dioxide samples with varying P/Ti atomic ratio were conveniently prepared via a conventional solgel route. The effects of phosphorus content and calcination temperature on the crystalline structure, grain growth, surface area, and the photocatalytic activity of P-modified TiO2 were investigated. The XRD results showed that P species slow down the particle growth of anatase and increase the anatase-to-rutile phase transformation temperature to more than 900°C. Kinetic studies on the P-modified TiO2 to degraded 4-chlorophenol had found that the TP5500 prepared by adopting a P/Ti atomic ratio equal to 0.05 and calcined at 500°C had an apparent rate constant equal to 0.0075 min 1, which is superior to the performance of a commercial photocatalyst Degussa P25 Kapp = 0.0045 min 1 and of unmodified TiO2 (TP0500) Kapp = 0.0022 min 1. From HPLC analyses, various hydroxylated intermediates formed during oxidation had been identified, including hydroquinone (HQ), benzoquinone (BQ) and (4CC) 4-chlorocatechol as main products. Phytotoxicity was assessed before and after irradiation against seed germination of tomato (Lycopersicon esculentum) whereas acute toxicity was assessed by using Folsomia candida as the test organism. Intermediates products were all less toxic than 4-chlorophenol and a significant removal of the overall toxicity was accomplished
基金support for this research was provided by the High-Level Scientific Research Cultivation Project at Hubei Minzu University,with the grant identifier PY22001the Guiding Projects from the Department of Education in Hubei Province,identified by the grant number B2018088.
文摘Recently,self-powered ultraviolet photodetectors(UV PDs)based on SnO_(2)have gained increasing interest due to its feature of working continuously without the need for external power sources.Nevertheless,the production of the majority of these existing UV PDs necessitates additional manufacturing stages or intricate processes.In this work,we present a facile,cost-effective approach for the fabrication of a self-powered UV PD based on p-Si/n-SnO_(2)junction.The self-powered device was achieved simply by integrating a p-Si substrate with a n-type SnO_(2)microbelt,which was synthesized via the chemical vapor deposition(CVD)method.The high-quality feature,coupled with the belt-like shape of the SnO_(2)microbelt enables the favorable contact between the n-type SnO_(2)and p-type silicon.The built-in electric field created at the interface endows the self-powered performance of the device.The p-Si/n-SnO_(2)junction photodetector demonstrated a high responsivity(0.12 mA/W),high light/dark current ratio(>103),and rapid response speed at zero bias.This method offers a practical way to develop cost-effective and high-performance self-powered UV PDs.
基金supported by the Department of Chemical and Petrochemical Engineering,Egypt-Japan University of Science and Technology.
文摘The steel industry produces many byproducts, requiring extensive land for storage and causing significant environmental contamination. Industrial effluents discharged into water bodies negatively impact both aquatic ecosystems and human health. To solve this problem, this study synthesized a composite of titanium dioxide (TiO2) and steel slag nanocomposites (SSNC) at a 1:2 mass ratio to create a robust photocatalyst for the treatment of synthetic wastewater. The efficacy of this catalyst in degrading various dye pollutants, including methylene blue (MB), was tested under simulated solar light conditions. Comprehensive analyses were conducted to assess the physical and chemical characteristics, crystalline structure, energy gap, and point of zero charge of the composite. The TiO2-SSNC composite catalyst exhibited excellent stability, with a point of zero charge at 8.342 and an energy gap of 2.4 eV. The degradation process conformed to pseudo-first-order kinetics. Optimization of operational parameters was achieved through the response surface methodology. Reusability tests demonstrated that the TiO2-SSNC composite catalyst effectively degraded up to 93.41% of MB in the suspended mode and 92.03% in the coated mode after five cycles. Additionally, the degradation efficiencies for various dyes were significant, highlighting the potential of the composite for broad applications in industrial wastewater treatment. This study also explored the degradation mechanisms and identified byproducts, establishing a pathway for contaminant breakdown. The cost-benefit analysis revealed a total cost of 0.842 8 USD per cubic meter for each treatment activity, indicating low operational and production costs. These findings underscore the promise of the TiO2-SSNC composite as a cost-effective and efficient alternative for wastewater purification.