NiO nanodot decorated In2S3 nanosheet arrays photoanode toward low-onset-potential photoelectrochemical hydrogen evolution

In this study, we demonstrate that modifying p-type NiO nanodots (NDs) on n-type In2S3 nanosheet arrays (NSAs) photoanode can significantly boost its photoelectrochemical (PEC) hydrogen evolution. The NiO NDs are deposited onto the In2S3 NSAs surface via an easy and facile photodeposition method. The optimized In2S3/NiO NSAs/NDs photoanode displays drastically boosted PEC water splitting activity. The optimized In2S3/NiO NSAs/NDs photoanode exhibits 167 % enhancement in the maximum photocurrent density compared to that of undecorated In2S3 NSAs photoanode in neutral electrolyte at 0 V vs. Ag/AgCl. Furthermore, in contrast with pure In2S3 NSAs photoanode, the In2S3/NiO NSAs/NDs photoanode exhibits a marked cathodic shift with a value of about 30 mV in the onset potential, substantially reducing water oxidation reaction energy barrier. And the photogenerated carriers of the In2S3 NSAs photoelectrode are efficiently transferred and separated in contrast with those of pure In2S3 NSAs photoelectrode. The present study offers a new strategy to enhance PEC water splitting performance of In2S3 photoanode through decreasing onset potential for water oxidation reaction.