Oxygen vacancies promoting photoelectrochemical performance of in 2 O 3 nanocubes

Abstract

This work reports a facile method for preparing the new photoactive In 2 O 3 films as well as their implementation in photoelectrochemical (PEC) application. We firstly investigated the relationship between oxygen vacancies (V O) and PEC performance and revealed a rule between them. We found that the optimized In 2 O 3-n sample yielded a photocurrent density up to 3.83â.mA/cm 2 in 1â.M Na 2 SO 4 solution under the solar illumination. It also gave efficiency as high as 75% over 400â.nm in the incident-photon-to-current-conversion efficiency (IPCE) spectrum, which is the best value for an In 2 O 3 photoanode reported. Moreover, the PEC performance of these films is enhanced as the V O increased and then decreased with further increasing V O. This two-side effect means V O can favor the photoelectron activation, or act as recombination centers to prohibit the generation of photocurrent. Making highly photoactive In 2 O 3 nanostructures in this work will open up new opportunities in various areas.