Boosting Alkaline Oxygen Evolution Kinetics by Tailoring the Noncovalent Interaction on CoOOH

Understanding the effect of noncovalent interactions of intermediates at the polarized catalyst-electrolyte interface is key to improving the kinetics of electrocatalytic reactions. Herein, we employ cobalt oxyhydroxide (CoOOH) as a model catalyst, select carboxylate-based additives to strategically modulate the interfacial electronic double layer (EDL), and investigate the effect of carboxylate anions on the oxygen evolution reaction (OER) kinetics under alkaline media. We demonstrate that the hydrogen bonds formed between oxygen atoms within -COO^- fragments of carboxylate anions and interfacial H₂O molecules can disrupt the arrangement of the hydration shell around K⁺, leading to fast migration of OH^- to the CoOOH surface. Experimental results, including rotating ring-disk electrode (RRDE) measurements, in situ X-ray absorption spectroscopy (XAS), in situ attenuated total reflectance surface-enhanced infrared absorption spectroscopy (ATR-SEIRAS), and ab initio molecular dynamics (AIMD) theory simulations, reveal that the negative electrostatic potential on the oxygen atom in the -COO^- fragments can partially neutralize the localized electric field generated by hydrated K⁺ ions in the electrolyte, which sufficiently destabilizes the adsorbed oxygenated intermediates and accelerates the deprotonation process, thereby leading to promoted charge accumulation and accelerated alkaline OER kinetics.