MOF‐Stabilized Pd Nanosheets With Exposed Active Crystal Planes for Efficient Hydrogen Evolution

Achieving the exposure of high‐energy active crystal planes is a very challenging issue due to the thermodynamic limitations. Herein, Pd nanosheets with exposed high‐energy (1–10) crystal planes were constructed on IRMOF via layer‐by‐layer (LBL) electrodeposition. The metal–organic framework (MOF) matrix prevents Pd nanosheets aggregation through spatial isolation, while Pd─N bonds with ─NH 2 groups in IRMOF stabilize the high‐energy Pd (1–10) crystal planes, enabling their continued activity under acidic hydrogen evolution reaction (HER) conditions. Benefiting from the intrinsically favorable hydrogen adsorption thermodynamics of the Pd (1–10) crystal plane and the high density of low‐coordination Pd sites, the optimized Pd/IRMOF‐3 achieves an ultralow overpotential of 15 and 370 mV at 10 and 1000 mA cm −2 , respectively, outperforming commercial Pt/C. Moreover, it exhibits outstanding durability, sustaining HER for 320 h at 10 mA cm −2 , accompanied by preserved crystallinity and surface chemistry after long‐term HER. This work demonstrates that MOF‐stabilized Pd nanosheets with exposed active crystal planes offer a design for achieving simultaneously high activity and long‐term stability of electrocatalysts, providing insights for the rational construction of next‐generation electrocatalysts.