The oxidation of water to dioxygen catalyzed by the Mn<sub>4</sub>Ca oxygen evolving complex in natural photosystem II provides 99% of the driving force for photosynthesis. Progress of developing artificial water oxidation catalysts has suggested that nickel is a promising metal for the design of molecular catalysts. However, high overpotential and limited catalyst stability are bottleneck challenges awaiting solutions. In this work, we employed redox active ligands to synthesize novel nickel complexes, a biomimetic strategy adopted by a number of metalloenzymes including photosystem II and galactose oxidase. Our results indicated that both the metal and the ligand are involved in the redox chemistry of water oxidation catalysis. The ability of tuning the redox potentials of the metal and the ligand independently has provided a convenient way of manipulating the 2-e<sup>-</sup> potential of the reactive oxidant, a great strategy of reducing the overpotential of nickel-catalyzed water oxidation catalysis.

Biomimetic, catalytic water oxidation by molecular nickel complexes with redox active ligands

253rd National Meeting (2017)

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.