Homogeneous Electrocatalytic Water Oxidation at Neutral pH by a Robust Macrocyclic Nickel(II) Complex

The development of an earth‐abundant, first‐row water oxidation catalyst that operates at neutral pH and low overpotential remains a fundamental chemical challenge. Herein, we report the first nickel‐based robust homogeneous water oxidation catalyst, which can electrocatalyze water oxidation at neutral pH and low overpotential in phosphate buffer. The results of DFT calculations verify that the OO bond formation in catalytic water oxidation prefers a HOOH coupling mechanism from a cis‐isomer of the catalyst.