In-situ construction of 2D/1D Bi2O2S/Bi2S3 heterojunction from the topological transformation of Bi2O2S with significantly enhanced photoelectrochemical performance

Bi 2 O 2 S has gradually attracted the interest of researchers due to its excellent carrier mobility and light absorption property . However, its application in photoelectrochemical water splitting is very limited. In this work, hydrothermal treatment is performed on the obtained Bi 2 O 2 S film. Bi 2 S 3 nanowires are in-situ evolved by the topological transformation of Bi 2 O 2 S, and heterojunction with atomic-level contact interface is constructed. The photocurrent density of Bi 2 O 2 S/Bi 2 S 3 photoelectrode at 1.23 V vs. RHE is 3.82 mA/cm 2 , which is 14 times that of monomer Bi 2 O 2 S. The Bi 2 O 2 S/Bi 2 S 3 heterojunction co-shared by Bi atoms has a close contact coupling interface, which stimulates stronger interfacial charge transfer. In addition, the 2D/1D morphology of the synthesized Bi 2 O 2 S nanosheets combined with Bi 2 S 3 nanowires by fine tuning builds a channel for fast carrier transport. This study provides reference and inspiration for the preparation of highly active heterostructures, and expands new paths for the design and application of Bi 2 O 2 S based photoelectrodes.