Fabrication of In2O3/In2S3 heterostructures for enhanced photoelectrochemical performance

Abstract

Constructing core/shell heterojunction has always been an effective strategy for photoelectrochemical (PEC) water splitting owing to special morphology characterization and band structure. Herein, we synthesized a series of In2O3/In2S3 core/shell structure photoanodes via a simple two-step hydrothermal method to improve the PEC performance of In2O3. Various methods were employed to investigate the influence of sulfurization time on the morphologies, microstructures, photoelectrochemical properties and band structures of the as-prepared photoanodes. The results indicated that the In2O3/In2S3-5 possessed stronger visible light absorption, faster charge transfer rate and higher electron carrier density, which resulted in an excellent PEC performance. Under visible light irradiation, the photocurrent density of the In2O3/In2S3-5 photoanode reached 0.53 mA cm−2 at 1.23 V vs RHE in 1 M NaOH solution, which was about twice as high as that of the pristine In2O3. Furthermore, the onset potential of the In2O3/In2S3-5 photoanode had an obvious negative shift (~200 mV) when compared to the pure In2O3 nanorod photoanode.