Atomic‐Scale Ru Skin Propels Alkaline Hydrogen Fuel Cells

ABSTRACT Developing highly efficient and durable Ru‐based hydrogen oxidation reaction (HOR) catalysts is essential for advancing anion exchange membrane fuel cell (AEMFC) technology. However, Ru‐type catalysts have suffered from unbalanced intermediate adsorption/desorption, resulting in suboptimal HOR activity and limited long‐term stability, particularly under practical AEMFC operating conditions. Here, we present a RuCo core–shell nanoplate featuring a Co core and an atomically scaled Ru skin shell (Co@Ru NPs), in which the unique core–shell structure and atomic Ru skin effectively optimize the adsorption/desorption balance of H * and OH * species while enhancing reaction kinetics in AEMFCs. Consequently, the Co@Ru NPs‐based fuel cell delivers an excellent peak power density (PPD) of 1.57 W cm −2 in H 2 ‐O 2 with an ultralow Ru loading of 0.05 mg cm −2 , which enables an exceptional anode specific power of 31.4 W mg Ru −1 , outperforming those of state‐of‐the‐art Ru‐type AEMFCs. Moreover, the Co@Ru NPs‐based fuel cell can be run stably at 0.5 A cm −2 for over 300 h, demonstrating the excellent stability of Co@Ru NPs for practical fuel cell applications.