Rapid industrialization has accordingly increased the demand for energy.This has resulted in the increasingly severe energy and environmental crises.Hydrogen production,based on the photocatalytic water splitting driv...Rapid industrialization has accordingly increased the demand for energy.This has resulted in the increasingly severe energy and environmental crises.Hydrogen production,based on the photocatalytic water splitting driven by sunlight,is able to directly convert solar energy into a usable or storable energy resource,which is considered to be an ideal alternative energy source to assist in solving the energy crisis and environmental pollution.Unfortunately,the hydrogen production efficiency of single phase photocatalysts is too low to meet the practical requirements.The construction of heterostructured photocatalyst systems,which are comprised of multiple components or multiple phases,is an efficient method to facilitate the separation of electron‐hole pairs to minimize the energy‐waste,provide more electrons,enhance their redox ability,and hence improve the photocatalytic activity.We summarize the recent progress in the rational design and fabrication of nanoheterostructured photocatalysts.The heterojunction photocatalytic hydrogen generation systems can be divided into type‐I,type‐II,pn‐junction and Z‐scheme junction,according to the differences in the transfer of the photogenerated electrons and holes.Finally,a summary and some of the challenges and prospects for the future development of heterojunction photocatalytic systems are discussed.展开更多
A new photochromic complex of Keggin type tungstophosphate acid/polyvinyl pyrrolidone system was prepared, and its thin films was made by the dipping method. Their photochromic properties were investigated by FTIR, UV...A new photochromic complex of Keggin type tungstophosphate acid/polyvinyl pyrrolidone system was prepared, and its thin films was made by the dipping method. Their photochromic properties were investigated by FTIR, UV Vis spectra. The salts were formed by the combination of the ion based on the N atoms in the polymeric molecules and H + of the acids. The UV Vis spectra showed that this type of system had an excellent photochromic behavior. The g values of ESR spectra for the one electron blues were the characteristic of tetragonal W(Ⅴ) complex in colored thin film. It was indicated that the charge could be transferred between the anion and cation under irradiation of UV light and the result in the oxidation of the cation and the reduction of the anion.展开更多
Under the background of increasing energy crisis and global warming,semiconductor-based photocatalysis has received tremendous attention due to its potential application in green energy production,CO_(2) reduction and...Under the background of increasing energy crisis and global warming,semiconductor-based photocatalysis has received tremendous attention due to its potential application in green energy production,CO_(2) reduction and pollutant degradation.The photocatalytic activity of semiconductors,however,remains low due to issues like fast recombination of photo-generated electron-hole pairs,limited electron mobility,restricted optical absorption or insufficient active sites.Designing appropriate heterojunctions is proved to be a promising method to address most of these issues and thus to improve the photocatalytic performance.In this review,the working mechanism of various heterojunctions is presented systematically.The most recent advances of strategies in designing and preparing efficient heterojunction photocatalysts are further summarized and some perspectives on the future directions in this field are provided.展开更多
基金supported by the National Natural Science Foundation of China (51572253,21271165)Scientific Research Grant of Hefei Science Center of CAS (2015SRG-HSC048)Cooperation between NSFC and Netherlands Organization for Scientific Research (51561135011)~~
文摘Rapid industrialization has accordingly increased the demand for energy.This has resulted in the increasingly severe energy and environmental crises.Hydrogen production,based on the photocatalytic water splitting driven by sunlight,is able to directly convert solar energy into a usable or storable energy resource,which is considered to be an ideal alternative energy source to assist in solving the energy crisis and environmental pollution.Unfortunately,the hydrogen production efficiency of single phase photocatalysts is too low to meet the practical requirements.The construction of heterostructured photocatalyst systems,which are comprised of multiple components or multiple phases,is an efficient method to facilitate the separation of electron‐hole pairs to minimize the energy‐waste,provide more electrons,enhance their redox ability,and hence improve the photocatalytic activity.We summarize the recent progress in the rational design and fabrication of nanoheterostructured photocatalysts.The heterojunction photocatalytic hydrogen generation systems can be divided into type‐I,type‐II,pn‐junction and Z‐scheme junction,according to the differences in the transfer of the photogenerated electrons and holes.Finally,a summary and some of the challenges and prospects for the future development of heterojunction photocatalytic systems are discussed.
文摘A new photochromic complex of Keggin type tungstophosphate acid/polyvinyl pyrrolidone system was prepared, and its thin films was made by the dipping method. Their photochromic properties were investigated by FTIR, UV Vis spectra. The salts were formed by the combination of the ion based on the N atoms in the polymeric molecules and H + of the acids. The UV Vis spectra showed that this type of system had an excellent photochromic behavior. The g values of ESR spectra for the one electron blues were the characteristic of tetragonal W(Ⅴ) complex in colored thin film. It was indicated that the charge could be transferred between the anion and cation under irradiation of UV light and the result in the oxidation of the cation and the reduction of the anion.
文摘Under the background of increasing energy crisis and global warming,semiconductor-based photocatalysis has received tremendous attention due to its potential application in green energy production,CO_(2) reduction and pollutant degradation.The photocatalytic activity of semiconductors,however,remains low due to issues like fast recombination of photo-generated electron-hole pairs,limited electron mobility,restricted optical absorption or insufficient active sites.Designing appropriate heterojunctions is proved to be a promising method to address most of these issues and thus to improve the photocatalytic performance.In this review,the working mechanism of various heterojunctions is presented systematically.The most recent advances of strategies in designing and preparing efficient heterojunction photocatalysts are further summarized and some perspectives on the future directions in this field are provided.
