Graded bandgap semiconductor thin film photoelectrodes  

作　　者：ZHAO Gaoling SONG Bin HAN Gaorong Hiromitsu Kozuka Toshinobu Yoko 

机构地区：[1]State Key Laboratory of Silicon Materials,Department of Materials Science and Engineering,Zhejiang University,Hangzhou 310027,China [2]Department of Physics and State Key Laboratory of Silicon Materials,Zhejiang University,Hangzhou 310027,China [3]Institute for Chemical Research,Kyoto University,Uji,Kyoto-Fu 611-0011,Japan

出　　处：《Chinese Science Bulletin》2001年第11期914-918,共5页

基　　金：the National Natural Science Foundation of China (Grant Nos. 59902006 and 69890230).

摘　　要：<Abstract>A graded bandgap oxide semiconductor thin film electrode was designed in order to obtain a photoelec-trochemically stable photoelectrode, with wide absorption range. The graded bandgap Ti1-xVxO2 film electrode was prepared by heating the stacked layers of V/Ti in varying ratios, which were coated on the substrate by the sol-gel method using the starting solution with various V/Ti ratios. XPS result showed that the composition gradient was achieved for the film. The Ti1-xVxO2 film electrode was found to be photoelectrochemically stable. Its photovoltage was about 360 mV. Obvious visible light photoresponse was observed for the Ti1-xVxO2 film electrode. Compared with the pure TiO2 electrode, the photocurrent onset potential of the Ti1-xVxO2 film electrode was shifted positively, probably because the accumulation of vanadium at the electrode surface causes the recombination of the electrons and holes, and the lowest level of the conduction band of Ti1-xVxO2 is lower than that of TiO2. ImpedanceA graded bandgap oxide semiconductor thin film electrode was designed in order to obtain a photoelec-trochemically stable photoelectrode, with wide absorption range. The graded bandgap Ti1?x V x O2 film electrode was prepared by heating the stacked layers of V/Ti in varying ratios, which were coated on the substrate by the sol-gel method using the starting solution with various V/Ti ratios. XPS result showed that the composition gradient was achieved for the film. The Ti1?x V x O2 film electrode was found to be photoelectrochemically stable. Its photovoltage was about 360 mV. Obvious visible light photoresponse was observed for the Ti1?x V x O2 film electrode. Compared with the pure TiO2 electrode, the photocurrent onset potential of the Ti1?x V x O2 film electrode was shifted positively, probably because the accumulation of vanadium at the electrode surface causes the recombination of the electrons and holes, and the lowest level of the conduction band of Ti1?x V x O2 is lower than that of TiO2. Impedance analysis showed that the donor density of the Ti1?x V2O2 film electrode was higher than that of TiO2 film electrode.

关 键 词：GRADED bandgap SOL-GEL method photoelectrode. 

分 类 号：O472.1[理学—半导体物理]