Synthesis of g-C₃N₄/CuS Heterojunction with Enhanced Photocatalytic Activity Under Visible-Light

Novel g-C₃N₄/CuS hybrid photocatalysts were synthesized successfully via a facile hydrothermal method. Characterization results of the photocatalysts showed that especial heterostructure had formed between g-C₃N₄ and CuS, and possess suitable matched band potential. The composite photocatalysts displayed strong UV-visible light absorption ability in the range from 200 to 800 nm. Photocatalytic performance of the photocatalysts were evaluated via photooxidation of methyl orange (MO) under visible-light irradiation. Hybrid photocatalysts showed better photocatalytic properties than that of pure g-C₃N₄ or CuS. The 60% g-C₃N₄/CuS sample proved the supreme photocatalytic property. The integrated g-C₃N₄ and CuS heterojunction elevated the separation efficiency of photogenerated electron-hole pairs, and increased the photo-decoloration efficiency of MO under visible-light irradiation. A four-cycle repeatability experiment was carried out to investigate the stability of hybrid photocatalysts in the photocatalyst reaction. Radical capture experiments proved that photogenerated e^-, h⁺ and .OH were responsible for MO photo-decoloration. In addition, the potential mechanism of the photocatalytic system g-C₃N₄/CuS+H₂O₂+vis are presented.