Synergistic Effect of Electronic Particle–Support Interactions on the Ir-Based Multiheterostructure for Acidic Water Oxidation

Abstract

Exploiting durable electrocatalysts with high specific activity for acidic water oxidation is a great challenge due to the high energy barrier for the multiple oxygen evolution reaction (OER) intermediates. Deliberately taking advantage of the synergistic effect of electronic particle–support interactions on both the particle and support may address this concern. Here, we deliberately design a multiheterostructure with an IrO2 shell-coated Ir core anchored on the Co3O4 framework as an efficient acidic OER electrocatalyst. Detailed characterizations (depth-resolved XPS, XANES, and EXAFS) of the electrocatalysts demonstrate that the electronic particle–support interactions lead to a unique electron transfer at the interface from IrO2 and Co3O4 to Ir. Such an electron transfer will result in compressed Ir–O bonds and Co–O bonds, thus simultaneously reducing free energies for OER intermediates on the surfaces of both IrO2 and Co3O4, sufficiently stimulating the synergistic effect to enhance OER activity and stability