A low Ir loading electrode of Ti/TiO2 NTs/IrRuOx based on self-supported TiO2 NTs interlayer for PEMWE

Developing a high-performance electrode with low Ir loading for the anodic oxygen evolution reaction (OER) stands as the primary challenge in advancing proton exchange membrane water electrolysis (PEMWE). In this study, we designed an electrode comprising a self-supported interlayer of TiO2 nanotubes (TiO2 NTs) on Ti felt, followed by a coating of IrRuOx on TiO2 NTs/Ti felt. Due to a significant electrochemical active area (ECSA) and lattice contraction, Ti/TiO2 NTs/IrRuOx-20 V effectively boost the oxygen evolution activity, achieving an Ir loading of 85.1 mu g cm-2 and an overpotential of only 190 mV@10 mA cm-2. Both the interlayer and IrRuOx coating contribute to increased durability. The stability test reveals that Ti/TiO2 NTs/IrRuOx-20 V remains stable for up to 300 h@10 mA cm-2 in 0.5 M H2SO4. Moreover, the electrode lasts 260 h@500 mA cm-2 in a full cell. This study suggests a promising direction for the design of future electrodes.