Tuning the oxygen vacancies and mass transfer of porous conductive ceramic supported IrOx catalyst via polyether-derived composite oxide pyrolysis: Toward a highly efficient oxygen evolution reaction catalyst for water electrolysis

Slow oxygen evolution reaction (OER) and material transport impedance in catalyst-coated membrane (CCM) are major challenges for the practical proton exchange membrane water electrolyzer (PEMWE). Herein, we present a novel OER catalyst by polyether-derived composite oxide pyrolysis with a multilevel porous support and abundant oxygen vacancies to boost efficiency and durability in water electrolysis. The formation of a heterointerface with abundant oxygen vacancies in IrO_x improves the catalytic activity and prevents IrO_x from peroxidation. Furthermore, the unique pore structure of the support facilitates the mass transport of the anode catalyst layer during water electrolysis at high current density, and the mass transport resistance of the water electrolyzer is only 0.0154 Ω cm² at 1.5 A cm⁻². When used in a PEMWE, the prepared electrocatalysts have an impressive electrochemical performance of 1.87 V at 3·A cm⁻² with an Ir loading of only 0.91 mg cm⁻². This approach highlights the importance of oxygen vacancies and transportation in the catalyst-support interface, providing a promising solution for high-rate practical water electrolysis.

Graphical Abstract

Efficient OER supported catalysts enriched with oxygen vacancies for PEMWE applications