Construction of 2D BiVO4-CdS-Ti3C2Tx Heterostructures for Enhanced Photo-redox Activities

Photocatalytic evolution of hydrogen and oxygen from water splitting over semiconductors is an efficient method for solar energy conversion. In this study, the 2D/2D BiVO4-CdS heterostructures with Ti3C2Tx (T-x=O, OH, F) as a co-catalyst were synthesized by two steps as the visible-light-driven photocatalysts. Compared with BiVO4 and CdS, the heterostructured catalysis exhibit greatly enhanced photocatalytic hydrogen and oxygen production performances and excellent photodegradation and photoreduction activities of methylene blue (MB) and potassium dichromate Cr(VI), respectively. The remarkable enhancement is attributed to the proposed Z-scheme carrier transfer derived from the 2D/2D BiVO4-CdS heterostructures. Charge separation and transfer of photoexcited electrons and holes pairs are further enhanced after loading Ti3C2Tx in the BiVO4-CdS heterostructures. The potential Z-scheme photocatalytic system and co-catalyst endows the BiVO4-CdS-Ti3C2Tx heterostructures with strong photo-redox capacity and excellent stability in solar energy conversion.