Hollow Zn0.01Co0.99 Se2/ZnIn2S4 Z-scheme heterogeneous photocatalyst with Strong internal electric field and Excellent surface electron transfer capability for Efficient Hydrogen Production

Abstract

Reasonable design and optimization of photocatalyst structure is an important strategy to realize sustainable hydrogen production. The rational design and interfacial tuning of Z-scheme heterojunctions remain challenging. Herein, a series of hollow cage-like Zn0.01Co0.99Se2/ZnIn2S4 Z-scheme heterojunction photocatalysts templated by cobalt-based bimetallic organic frameworks is successfully obtained via a hydrothermal approach. As expected, the optimized catalysts exhibit excellent hydrogen production performance without noble metal co-catalysts, which is mainly attributable to the synergistic effect of abundant active sites, strong light trapping and effective charge separation. Spectroscopic characterization and density functional theory (DFT) calculations indicate that the doping of Zn ions leading to more photogenerated carriers and faster charge transfer rates inside the heterojunction is another key factor in improving the catalytic performance. This work provides a feasible strategy for the optimization and design of Z-scheme heterojunctions through structural and interfacial engineering.