Trimetallic Au@RhCu Core‐Shell Nanodendrites as Efficient Bifunctional Electrocatalysts toward Hydrogen and Oxygen Evolution Reactions

Developing efficient and stable electrocatalysts for water splitting is highly desirable due to growing energy demands. Here, Au@RhCu nanodendrites with core‐shell nanostructure were facile generated via seed‐mediated method. Through composition optimization, the Au@Rh3Cu nanodendrites show excellent hydrogen evolution reaction (HER) activity with an overpotential of 83 mV at the current density of 10 mA cm−2, together with a small Tafel slope of 33.4 mV dec−1. Meanwhile, the Au@Rh3Cu nanocrystals are also a good oxygen evolution reaction (OER) catalyst with an overpotential of 415 mV (at 10 mA cm−2) and a Tafel slope of 127 mV dec−1. Additionally, the Au@Rh3Cu exhibits excellent stability for both HER and OER. Such attractive catalytic performance can be assigned to the large surface area produced by the unique core‐shell dendritic nanostructure, the synergistic effect between different metal elements and the positive influence of Au seeds. This work would offer a reliable pathway for the design of multimetallic core‐shell dendritic nanostructures as promising electrocatalysts toward water splitting. We use a facile seed‐mediated method to synthesize Au@RhCu nanocrystals with core‐shell nanodendritic structure. Impressively, the Au@Rh3Cu nanodendrites exhibit excellent HER and OER activity compared to commercial Rh/C and commercial RuO2.