摘要
Cr-doped Sr TiO_(3)/Ti-dopedα-Fe_(2)O_(3) heterojunction has been constructed by an ingenious way,i.e.using segregation titanium oxide on the surface of the Ti-dopedα-Fe_(2)O_(3) electrode to in situ prepare Cr-doped SrTiO_(3).After construction of the heterojunction,the photocurrent onset potential for water oxidation on a Ti4+dopedα-Fe_(2)O_(3) cathodically shifts by about 100 mV.Moreover,the cathodic shift of the onset potential can be preserved well even after a long time running.The results indicate the effectiveness and credibility of the fabricated heterojunction.In order to make clear the reason for the onset potential shift,the asprepared Ti-dopedα-Fe_(2)O_(3) and Cr-doped SrTiO_(3)/Ti-dopedα-Fe_(2)O_(3) samples were investigated by X-ray photoelectron spectroscopy,electrochemical impedance spectroscopy,X-ray diffraction spectroscopy,etc.Based on the experimental evidences,it is proposed that cathodic shift of the onset potential is mainly due to the enhanced charge separation at the photoanode surface.This strategy can offer a reference to construct heterojunction on other films especially for those with surface segregation.
基金
financially supported by the National Natural Science Foundation of China(Nos.61474064 and 61504063)
the Natural Science Foundation of Jiangsu Province(No.BK20150836)
the Jiangsu National Synergetic Innovation Center for Advanced Materials(SICAM)
the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD,No.YX030003)
the Synergistic Innovation Center for Organic Electronics and Information Displays。
