Construction of hierarchical photocatalysts by growing ZnIn2S4 nanosheets on Prussian blue analogue-derived bimetallic sulfides for solar co-production of H2 and organic chemicals

Abstract

Abstract Exploring highly efficient bifunctional photocatalysts for simultaneous H2 evolution and organic chemical production in pure water represents a green route for sustainable solar energy storage and conversion. Herein, a facile strategy was explored for preparing a hierarchical porous heterostructure of Fe4Ni5S8@ZnIn2S4 (FNS@ZIS) by the in situ growth of ZIS nanosheets on Prussian blue analogue (PBA)-derived bimetallic FNS sulfides. A series of FNS@ZIS hierarchical structures were facilely prepared by adjusting the loading amount (n%) of FNS (n = 19, 26, and 32 for FNS@ZIS-1-3). These structures can efficiently drive the solar co-production of H2 and organic chemicals. The optimal co-production was achieved with FNS@ZIS-2, affording a H2 evolution rate of 10465 μmol·g−1·h−1, along with high selectivity for the oxidation of benzyl alcohol to benzaldehyde (>99.9%). The performance was 22 and 31 times higher than that of FNS and ZIS, respectively, and even superior to the state-of-the-art results achieved using various sacrificial agents. Further mechanistic study indicated that the unique hierarchical core/shell architecture can facilitate interfacial charge separation, afford bimetallic synergy, abundant active sites and excellent photostability. This work highlights a simple and efficient method for preparing porous multimetallic hierarchical structures for the solar co-production of organic chemicals and H2 fuel.