A Hybrid S‐Scheme WS₂/BiOI Heterojunction Photocatalyst for Wastewater Treatment

Abstract

There is a growing demand for efficient methods to decrease hazardous organic contaminants in wastewater. Herein, a novel S‐scheme WS2/BiOI heterojunction photocatalyst was prepared by a one‐pot solvothermal process. The structural morphology, crystal structure and optical absorption studies were studied. The sugar‐like nanocrystals of WS2 are deposited on 3D‐BiOI marigold flowers, providing high surface area with increased visible light absorption. The photocatalytic activity of the synthesized materials was studied by visible light degradation of Rhodamine‐B (RhB). The optimized 20 wt.% WS2 in the composite photocatalyst (band gap 2.25 eV) exhibited a 98.9 % photocatalytic degradation activity with a rate constant of 0.0940 min−1 with performance retained after 3 consecutive recycling runs. Photoelectrochemical studies revealed excellent stability, increased separation and migration ability of charge carriers with lower charge resistance in the optimized WS2/BiOI photocatalyst.