Efficient Light-Driven Carbon-Free Cobalt-Based Molecular Catalyst for Water Oxidation

摘要

The abundant-metal-based polyoxometalate complex [Co_4(H_2O)_2(PW_9O_(34))_2]~(10-) is a hydrolytically and oxidatively stable, homogeneous, and efficient molecular catalyst for the visible-light-driven catalytic oxidation of water. Using a sacrificial electron acceptor and photosensitizer, it exhibits a high (30%) photon-to-O_2 yield and a large turnover number (>220, limited solely by depletion of the sacrificial electron acceptor) at pH 8. The photocatalytic performance of this catalyst is superior to that of the previously reported precious-metal-based polyoxometalate water oxidation cata-lyst[{Ru_4O_4(OH)_2(H_2O)4}(γ-SiW_(10)O_(36))_2]~(10-).