Intramolecular hydroxyl nucleophilic attack pathway by a polymeric water oxidation catalyst with single cobalt sites

Abstract Exploration of efficient water oxidation catalysts (WOCs) is the primary challenge in conversion renewable energy into fuels. Here we report a molecularly well-defined heterogeneous WOC with Aza-fused, π-conjugated, microporous polymer (Aza-CMP) coordinated single cobalt sites (Aza-CMP-Co). The Aza-CMP-Co exhibited superior activity under alkaline and near-neutral conditions. Moreover, molecular nature isolated catalytic makes reliable model for studying mechanism. By combination experimental theoretical results, pH-dependent nucleophilic attack pathway O-O bond formation was proposed. Under conditions, intramolecular hydroxyl (IHNA) process which adjacent -OH group nucleophilically attacks Co 4+ =O identified as rate-determining step. This leads to lower activation accelerated kinetics than those intermolecular (WNA) pathway. study provides significant insights crucial function electrolyte pH catalysis enhancement by regulation IHNA