EDA-assisted synthesis of multifunctional snowflake-Cu_(2)S/CdZnS S-scheme heterojunction for improved the photocatalytic hydrogen evolution

摘要

The charge separation efficiency is one of the main factors affecting the solar photocatalytic decomposition of water to produce hydrogen.Constructing a unique heterojunction can accelerate the separation and transfer of photo-generated charges,and effectively improve the photocatalytic efficiency,which is considered a potential strategy.Accordingly,the 2%Cu_(2)S/CZS step-scheme(S-scheme)heterojunction based on morphology and electronic structure was successfully prepared via simple hydrothermal method.Compared with the monomer Cu_(2)S and Cd Zn S,the hydrogen evolution rate of 2%Cu_(2)S/CZS samples is significantly increased.In particular,the 2%Cu_(2)S/CZS not only shows high hydrogen evolution rate of 5904μmol g^(-1)h^(-1)(3.19 times than original Cd Zn S),but also presents preferable cyclic endurance.According to the characterization,we believe that the introduction of Cu_(2)S has the following three advantages:(i)The snowflake structure of Cu_(2)S reduces the agglomeration of granular Cd Zn S.(ii)The Cu_(2)S with narrow band gap broadens the light response range of the composite catalyst.(iii)The Cu_(2)S was introduced into Cd Zn S to form S-scheme heterojunction,which accelerated the separation and transfer of photo-generated charge.This work broadens the idea of designing efficient photocatalyst of hydrogen evolution.