Facile synthesis of AuIr alloy nanoparticles and their enhanced oxygen evolution reaction performance under acidic and alkaline conditions.

The development of electrocatalysts that can maintain high reactivity and stability over a wide pH range during electrolysis reactions is essential for the realization of a clean hydrogen energy society. Herein, we report the synthesis of AuIr alloy nanoparticles (NPs) with an excellent oxygen evolution reaction (OER) performance over a wide pH range. The NPs were synthesized via an antisolvent crystallization-based method and maintained their small sizes regardless of adjustments in the ratio of the Au/Ir precursor. AuIr/C exhibited low overpotential and good long-term stability under acidic and alkaline conditions compared with the Ir/C and commercial RuO 2 . The enhanced OER performance of AuIr/C was attributed to efficient charge transfer, resulting in an optimal synergistic effect of electrons.