Bioinspired Trinuclear Copper Catalyst for Water Oxidation with a Turnover Frequency up to 20000 s-1

Solar-powered water splitting is a dream reaction for constructing an artificial photosynthetic system for producing solar fuels. Natural photosystem II is a prototype template for research on artificial solar energy conversion by oxidizing water into molecular oxygen and supplying four electrons for fuel production. Although a range of synthetic molecular water oxidation catalysts have been developed, the understanding of O-O bond formation in this multielectron and multiproton catalytic process is limited, and thus water oxidation is still a big challenge. Herein, we report a trinuclear copper cluster that displays outstanding reactivity toward catalytic water oxidation inspired by multicopper oxidases (MCOs), which provides efficient catalytic four-electron reduction of O-2 to water. This synthetic mimic exhibits a turnover frequency of 20000 s(-1) in sodium bicarbonate solution, which is about 150 and 15 times higher than that of the mononuclear Cu catalyst (F-N2O2Cu, 131.6 s(-1)) and binuclear Cu-2 complex (HappCu(2), 1375 s(-1)), respectively. This work shows that the cooperation between multiple metals is an effective strategy to regulate the formation of O-O bond in water oxidation catalysis.

Automated summary

Researchers have developed a copper cluster inspired by multicopper oxidases, which shows remarkable catalytic reactivity towards water oxidation for efficient four-electron reduction of O-2 to water. This synthetic mimic demonstrates the effectiveness of cooperation between multiple metals in regulating O-O bond formation in water oxidation catalysis.