Covalent-Coupled Zn<sub>0.4</sub>Cd<sub>0.6</sub>S with g-C<sub>3</sub>N<sub>4</sub> as a Sheet-on-Sheet Z-Scheme Photocatalyst for Water Splitting
Yanan Li, Yan Wang, Wei Wang, Xiao Yu, Li Zhang, Liu Deng, You‐Nian Liu
Abstract
Development of heterojunction to improve charge separation efficiency is one of the main strategies to enhance the hydrogen production performance of photocatalysts. Herein, we fabricate a 2D/2D Z-scheme heterojunction-coupled Zn 0.4 Cd 0.6 S with g-C 3 N 4 by in situ hydrothermal approach. The sheet-on-sheet architecture provides full contact of heterojunction to accelerate interfacial charge transfer and increase surface-active sites. Additionally, the Zn–N coordination bond acts as a strong interfacial interaction between Zn 0.4 Cd 0.6 S and g-C 3 N 4, and photogenerated charges are spatially separated along the Z-scheme mechanism. In particular, under visible-light (λ ≥ 420 nm) irradiation, the optimal photocatalyst exhibits a high hydrogen production (H 2 production rates: 7.69 mmol g –1 h –1 ) without any cocatalysts, 4 times higher than that of the g-C 3 N 4 photocatalyst using Pt as a cocatalyst. The catalyst has a long-term stability of up to 50 h. Therefore, a direct Z-scheme heterojunction with intimate contact and a well-definite bridging chemical bond could be a prospective photocatalyst for hydrogen generation.