In-situ controlled synthesis of BiOI/Bi2S3 Z-scheme heterostructure with enriched oxygen vacancies for efficient photocatalytic removal of hexavalent chromium

The continuous increase of heavy metal pollution has seriously affected the ecological environment and human health, and photocatalysis technology is considered to be one of the most effective and environmentally friendly treatment methods. Herein, BiOI/Bi2S3 Z-scheme heterostructure photocatalyst with abundant oxygen vacancies was fabricated and applied for the removal of hexavalent chromium (Cr(VI)). The tightly contact interface of in situ heterostructure and abundant oxygen vacancies can accelerate charge transport and improve the photogenerated carrier separation efficiency. The unique charge transmission path of the Z-scheme heterostructure endows the material with superior redox ability. BiOI/Bi2S3 with optimized ratio can achieve effective reduction of Cr(VI) with the efficiency of 95.6 % under 10 min visible light illumination This work offers a promising photocatalyst for promoting the disposal of chromium-containing wastewater.