Bimetallic zeolite-imidazole framework-based heterostructure with enhanced photocatalytic hydrogen production activity

Abstract

Bimetallic zeolite-imidazole frameworks with controllable flat band position, band gap and hydrogen evolution reaction characteristics were adopted as a photocatalytic hydrogen production catalyst. Furthermore, the g-C₃N₄–MoS₂ 2D–2D surface heterostructure was introduced to the ZnM-ZIF to facilitate the separation as well as utilization efficiency of the photo-exited charge carriers in the ZnM-ZIFs. On the other hand, the ZnM-ZIFs not only inhibited the aggregation of the g-C₃N₄–MoS₂ heterostructure, but also improved the separation and transport efficiency of charge carriers in g-C₃N₄–MoS₂. Consequently, the optimal g-C₃N₄–MoS₂–ZnNi-ZIF exhibited an extraordinary photocatalytic hydrogen evolution activity 214.4, 37.5, and 3.7 times larger than that of the pristine g-C₃N₄, g-C₃N₄–ZnNi-ZIF and g-C₃N₄–MoS₂, respectively, and exhibited a H₂-evolution performance of 77.8 μmol h⁻¹ g⁻¹ under UV-Vis light irradiation coupled with oxidation of H₂O into H₂O₂. This work will furnish a new MOF candidate for photocatalysis and provide insight into better utilization of porous MOF-based heterostructures for hydrogen production from pure water.