Ce-Doped IrO<sub>2</sub> Electrocatalysts with Enhanced Performance for Water Oxidation in Acidic Media
Yahui Wang, Shaoyun Hao, Xiangnan Liu, Qiqi Wang, Zhiwei Su, Lecheng Lei, Xingwang Zhang
Abstract
Electrocatalytic water splitting in acidic media based on a proton-exchange membrane (PEM) is a promising technique for the large-scale production of hydrogen. However, developing electrocatalysts with high activity and excellent stability for an oxygen evolution reaction (OER) in acidic media is still a big challenge. Herein, a Cex-IrO2 catalyst supported on N-doped porous carbon (NPC) was developed via doping Ce into IrO2 nanoparticles. The Cex-IrO2 nanoparticles were uniformly distributed on NPC due to the high surface area. The optimized Ce0.2-IrO2@NPC delivers a low overpotential of 224 mV and excellent stability of 100 h in 0.5 M H2SO4 at 10 mA cm–2. Density functional theory (DFT) calculations indicated that the introduction of Ce could modify the electronic structure of IrO2, decreasing the energy barrier of the rate-determining step for OER and enhancing the electrochemical OER performance. Our work opens up a new way of developing anodic electrocatalysts, which can be stably applied in acidic media.