A library of copper-peptide/peptidomimetic complexes to explore the effect of ligand framework modification on electrocatalytic water oxidation

Inspired by the process of water oxidation during photosynthesis, researchers have developed mononuclear and polynuclear transition metal complexes as homogeneous water oxidation catalysts. While water oxidation catalysis by mononuclear copper-peptide complexes with N4 motif has been briefly explored, there is limited research on how systematically changing individual components of the ligand framework can enhance water oxidation catalysis. We report the synthesis and characterization of a library of twenty-eight copper (II) peptide/peptidomimetic complexes, each incorporating a systematic ligand framework change. Their electrocatalytic water oxidation properties were investigated through cyclic voltammetry studies in a pH 11 buffer medium. These studies offer novel insight into how to enhance the water oxidation catalysis abilities of mononuclear and polynuclear copper-peptide/peptidomimetic complexes by modifying the ligand framework.