摘要
Herein,a cocatalyst was extensively used to enhance the photocatalytic water oxidation performance.In a cocatalyst/semiconductor system,charge transfer between a semiconductor and cocatalyst is a crucial process for the photoelectrochemical(PEC)water oxidation performance;however,the influence of surface states on charge transfer has rarely been discussed.In this study,Al_(2)O_(3)was inserted into the CoPi/Ti-Fe_(2)O_(3)interface to fabricate a CoPi/Al_(2)O_(3)/Ti-Fe_(2)O_(3)photoanode.CoPi/Al_(2)O_(3)/Ti-Fe_(2)O_(3)showed a notable improvement in the photocurrent density.A combination of UV-vis diffuse reflectance spectroscopy(DRS),surface photovoltage spectroscopy(SPS),chopped light photocurrent,and photocurrents under different chopped light frequencies was used to study the real role of Al_(2)O_(3)in the charge transfer process.It was found that Al_(2)O_(3)passivated the surface states of Ti-doped Fe_(2)O_(3),leading to a better interfacial charge transfer between Ti-doped Fe_(2)O_(3)and CoPi,resulting in the enhanced PEC water oxidation performance.
基金
the National Basic Research Program of China(973 Program)(2013CB632403)
the National Natural Science Foundation of China(No.51572106)
the Science and Technology Developing Funding of Jilin Province(No.20150203009GX).
