IrO2 supported on TiC and Ti2AlC for improved oxygen evolution reaction performances for proton exchange membrane water electrolyzer

Abstract

Generating a cost-effective precious-metal catalyst is essential for achieving low-cost, large-scale green hydrogen production.Since the majority of the overpotential in the proton exchange membrane water electrolyzer arises during the oxygen evolutionreaction (OER), the remarkable performance of the IrO2 makes it an ideal anodic catalyst. Herein, a simple, straightforwardmethod was used to prepare an IrO2-loaded transition-metal carbide-supported catalyst. The IrO2 nanoparticles were loadedon TiC (IrxTC 1-x) and Ti2AlC (IrxTAC 1-x) at 20 to 80 wt% IrO2 loadings, using the modified Adams fusion method. A diameterof 2 nm was obtained to exhibit improved OER performance in 0.5 M H2SO4 compared with commercial IrO2. The catalystsshowed a uniform distribution of IrO2 nanoparticles on the supports. Overpotentials of 260 and 250 mV were obtainedfor Ir80TC20 and Ir80TAC20 at 10 mA cm−2. The prepared Ir80TC20 and Ir80TAC20 showed good OER activity, delivering−2 −210 mA cm at 1.47 and 1.46 V versus RHE, respectively. The catalysts exhibited OER stability at 10 mA cm for 73 and58 h, respectively, for Ir80TC20 and Ir80TAC20. The precursor solution proved significant recyclability, and the study demonstrateda new approach to rapidly design low-cost, high-performance anodic catalysts for overall OER performance.