Highly dispersed Ir nanoparticles on Ti3C2Tx MXene nanosheets for efficient oxygen evolution in acidic media

The industrialization of hydrogen production technology through polymer electrolyte membrane water splitting faces challenges due to high iridium (Ir) loading on the anode catalyst layer. While rational design of oxygen evolution reaction (OER) electrocatalysts aimed at effective iridium utilization is promising, it remains a challenging task. Herein, we present exfoliated Ti 3 C 2 T x MXene as a highly conductive and corrosion-resistant support for acidic OER. We develop an alcohol reduction method to achieve uniform and dense loading of ultrafine Ir nanoparticles on the MXene surface. The IrO 2 /TiO x heterointerface is formed in situ on the Ir@Ti 3 C 2 T x MXene surface, acting as a catalytically active phase for OER during electrocatalysis. The electron interactions at the IrO 2 /TiO x heterointerface create electron-rich Ir sites, which reduce the adsorption properties of oxygen intermediates and enhance intrinsic OER activity. Consequently, the prepared Ir@Ti 3 C 2 T x exhibits a mass activity that is 7 times greater than that of the benchmark IrO 2 catalyst for OER in acidic media. In addition, the /Ti 3 C 2 T x MXene support can stabilize the Ir nanoparticles, so that the stability number of Ir@Ti 3 C 2 T x MXene is about 2.4 times higher than that of the IrO 2 catalyst.