One-dimensional amorphous porous iridium–ruthenium oxide for efficient acidic oxygen evolution reaction

Abstract

The acidic oxygen evolution reaction (OER) is a four-electron transfer process with slow kinetics and a high overpotential, which is greatly hindering the development of water electrolysis. But pure iridium-based catalysts or pure ruthenium-based catalysts find it difficult to achieve the required performance with both high activity and high stability. Here, we have successfully prepared one-dimensional amorphous porous iridium–ruthenium bimetallic oxide nanobelts, which exhibit a low overpotential of 204 mV at 10 mA cm⁻² and high-quality activity of 119 A g_Ir+Ru⁻¹ at 1.45 V_RHE in acidic OER. More importantly, as an anode, amorphous porous iridium–ruthenium oxide nanobelts remain stable over 350 h of operation at 1.8 V in a proton exchange membrane electrolyzer (PEM). The interaction of iridium and ruthenium in the amorphous structure successfully compensates for the defects of the single components, providing a basis for the design of acidic OER catalysts.