rGO spatially confined growth of ultrathin In2S3 nanosheets for construction of efficient quasi-one-dimensional Sb2Se3-based heterojunction photocathodes

Abstract

Antimony selenide (Sb 2 Se 3 ) is a narrow-bandgap semiconductor that has been increasingly used as an excellent light-harvesting material in photoelectrocatalysis. The unique connections of the one-dimensional (Sb 4 Se 6 ) n ribbon structural units determine the high anisotropy of their carrier transport. In this study, a reduced graphene oxide (rGO)modified quasi-one-dimensional Sb 2 Se 3 @In 2 S 3 light-trapping heterostructure was successfully constructed by vapor transport deposition followed by an in situ hydrothermal method. The results showed that the thickness of the in situ grown nonlayered In 2 S 3 nanosheets was significantly reduced from 30 to 10 nm under the space-confinement effect of rGO, facilitating the construction of light-trapping nanostructures and increasing the electrochemically active surface area of the photoelectrode. The quasi-one-dimensional Sb 2 Se 3 @In 2 S 3 -rGO nanorod photoelectrode achieved a higher photocurrent density (1.169 mA cm −2 ), which was 2 and 16 times higher than that of Sb 2 Se 3 @In 2 S 3 and pristine Sb 2 Se 3 , respectively. The ultrathin In 2 S 3 nanosheets were co-modified with rGO nanosheets to fabricate a brush-like composite photoelectrode that exhibited favourable stability with an average hydrogen production rate of 16.59 μmol cm −2 h −1 under neutral conditions. The experimental results and theoretical calculations both showed that the significant improvement in photoelectrochemical performance can be perfectly explained by the type-II heterojunction mechanism. This study provides a new exploration to design rGO-modified composite photoelectrodes for photoelectrochemical applications.

TiO2 spatially confined growth of Sb2(S,Se)3@TiO2 NT heterojunction photoanodes and their photoelectrochemical properties

“…6,7 Semiconductor PEC water splitting technology is considered to be one of the most promising technologies for solar energy conversion and utilization at present. 8,9 Therefore, how to use solar energy for efficient hydrogen production from water splitting has become a research hotspot for national and international scholars. On this basis, the selection of suitable semiconductor materials has become a top priority.…”