Copper(II) Catalysis of Water Oxidation

摘要

As the terminal step in Photosystem II (PSII), and a potential half-reaction for artificial photosynthesis, water oxidation (2H2O→O2 + 4H~+ + 4e~-) is a key reaction, but it imposes a significant mechanistic challenge in its requirements for both 4e~-/4H~+ loss and O-O bond formation. Rapid progress has recently been made based with single site polypyridyl Ru and Ir complexes, pre-prepared Mn oxide clusters, Co and Ni clusters that spontaneously form in solution, CO3O4 (spinel) particles, cobalt-based polyoxometal-lates, colloidal IrO2·nH2O, amorphous iridium oxide deposited from organometallic precursors, and, most recently, copper-bipyridine complexes.1161 There is a continuing need for stable, rapid, and easily accessible catalysts for this reaction, ideally based on earth-abundant elements.