Synergistic metal halide perovskite@metal-organic framework hybrids for photocatalytic CO reduction.

The photocatalytic reduction of carbon dioxide (CO) into multi-electron carbon products remains challenging due to the inherent stability of CO and slow multi-electron transfer kinetics. Here in, we synthesized a hybrid material, cesium copper halide (CsCuI) intercalated onto two-dimensional (2D) cobalt-based zeolite framework (ZIF-9-III) nanosheets (denoted as CsCuI@ZIF-1) through a simple mechanochemical grinding. The synergy in the hybrid effectively reduces CO to carbon monoxide (CO) at 110 μmol/g/h and methane at 5 μmol/g/h with high selectivity, suppressing hydrogen evolution. Further, we have investigated additional CsCuI@ZIF hybrids with varying ZIF-9-III amounts, confirming their selective CO reduction to methane over hydrogen. Density functional theory (DFT) calculations reveal a non-covalent interaction between CsCuI and ZIF-9-III, with electron transfer suggesting potential for improved photocatalysis.