Novel Sb₂S₃-3,4,9,10-Perylene Tetracarboxylic Acid Composite for Enhanced Photocatalytic Reduction of Cr(VI) in Aqueous Media.

The construction of organic-inorganic semiconductor heterojunctions is an important way to improve the photocatalytic performance of semiconductors and inhibit the recombination of photogenerated charge carriers. In this paper, a novel Sb₂S₃-3,4,9,10-perylene tetracarboxylic acid (Sb₂S₃-PTCA) heterojunction was prepared by hydrothermal method. Compared with Sb₂S₃ and PTCA, Sb₂S₃-PTCA composite catalyst had better photocatalytic reduction ability for Cr(VI) in aqueous solution under visible light conditions. The optimized Sb₂S₃-1.0 wt.% PTCA heterostructures exhibited significantly enhanced photocatalytic activity compared to pure Sb₂S₃ and PTAC, achieving a complete Cr(VI) reduction rate of 100 % in just 50 min. This will lead to cleaner effluent water being discharged into the environment, thereby reducing pollution and protecting aquatic ecosystems. The enhanced photocatalytic efficacy exhibited by the Sb₂S₃-PTCA heterostructure stems from the creation of a type II heterojunction, which facilitates a more proficient dissociation and transportation of the electron-hole pairs, thus contributing to its superior performance.