Ligand Modulation of Active Sites to Promote Electrocatalytic Oxygen Evolution.

Abstract

Rationally designed catalysts hold the key to address the sluggish kinetics of oxygen evolution reaction (OER). However, engineering the active sites of such catalysts still faces grand challenges. This study proposes a feasible ligand modulation strategy to boost the OER catalytic activity of cobalt-iron oxyhydroxide ((Fe,Co)OOH). The 2-methylimidazole (MI) ligand coordination on (Fe,Co)OOH reduces the orbital overlap between the Fe/Co 3d and O2p, which weakens the adsorption to oxygen-containing intermediates and thus facilitates the unfavorable O2 desorption. As a result, the MI ligand modulated (Fe,Co)OOH achieves an excellent OER performance with low overpotentials (230/290mV at 10/100mAcm-2 ) and excellent durability (>155h). This study provides a novel ligand modulation strategy for the design of OER catalysts.