A CdS@(PEA)₂SnBr₄ Heterojunction Photocatalyst for High-efficiency Hydrogen Production

The uncertain movement and high recombination of photo-generated charges lead to a low conversion efficiency for photocatalytic hydrogen evolution. The path to address such problem is to construct a high-efficiency organic/inorganic heterojunction. Quasi-2D (PEA)₂SnBr₄ has the better charge transport characteristics and more negative reduction potential compared with CdS. Herein, a CdS@(PEA)₂SnBr₄ heterojunction is firstly constructed via in-situ loading CdS nanoparticles on the surface of (PEA)₂SnBr₄ nanosheets. The interaction between CdS and (PEA)₂SnBr₄ can effectively separate photo-generated carriers via controlling the carriers of the interface migration to retain the high-energy photo-generated electrons and holes, respectively. Under the simulated sunlight, the CdS@(PEA)₂SnBr₄ heterojunction with optimum proportion attains a high photocatalytic hydrogen production rate of 13.38 mmol/g/h, up to 2.89 times compared with CdS. More importantly, the CdS@(PEA)₂SnBr₄ heterojunction possesses a beneficial stability after recycling four times. This work offers a new design thought for the construction of the photocatalytic heterojunction to the inorganic/organic system.