Regulating the adsorption behavior of intermediates on Ir–W@Ir–WO 3−x boosts acidic water oxidation electrocatalysis

Tungsten oxide with strong acid resistance and weak O-binding ability could potentially achieve a tradeoff on the O-binding property by constructing W and Ir dual sites for acidic oxygen evolution reaction (OER) catalysis. However, the formation of peroxide intermediate during OER process could react with tungsten oxide to produce soluble species, severely limiting its application. Herein, we construct Ir-W@Ir-WO3-x core-shell nanoparticles with the Ir-W metallic core and Ir-doped WO3-x (Ir-WO3-x) shell, which can deliver an impressive overpotential of 261 mV at 10 mA cm-2 for acidic OER catalysis and extraordinary catalytic stability. Spectroscopic analysis manifests that the Ir-W@Ir-WO3-x could substantially suppress peroxide species formation and effectively avoid the peroxide-induced corrosion during OER process. Theoretical studies reveal that the moderate O-binding capability on Ir-W@Ir-WO3-x not only accelerates the catalytic kinetics, but also restrains the hydroperoxide formation. This work sheds light on the rational design of OER catalysts by modulating the adsorption behavior of oxygen-containing intermediates.