Synergistic effect of Z-scheme junction and core–shell architecture over NH2-MIL-125@Ag@AgCl ternary heterojunction for cooperative CO and H2O2 production

Abstract

Herein, a NH2-MIL-125(Ti)@Ag@AgCl (NM@Ag@AgCl) stacked core–shell heterojunction with Z-scheme carrier transfer mechanism was developed to fulfil the goal of synchronous reactions of CO2 reduction and H2O oxidation. In detail, the NM@Ag@AgCl was obtained by in-situ loading the AgCl as the shell-inorganic semiconductor on the octahedral NM as the core-organic semiconductor, followed by in-situ transforming part of the AgCl shell into the plasmonic Ag nanoparticles using a photo-reduction method. As a result, the interface effects of core–shell architecture majorized by the Ag electronic mediator can favor the transmission of photogenerated carriers and reduce electron transport resistance; while the plasmonic Ag mediated Z-scheme mode with a giant internal electronic field provided a strong driving force to recombine the carriers with weak redox ability, reserving the carrier with strong redox ability on the NH2-MIL-125-core and AgCl-shell for the simultaneous reactions. The CO and H2O2 yields of the optimal NM@Ag@AgCl were 6.02 and 5.43 μmol⋅g−1⋅h−1, which were 3.31 and 4.02 times that of the NM, respectively. This study furnishes a novel thread for the design of core–shell organic–inorganic heterojunction with high interfacial charge transfer for realizing the simultaneous reactions.