Rammed earth walling-inspired catalyst layer construction for robust hydrogen evolution at ampere-level current density

Industrial-scale gas evolution reactions (GERs) are central to energy conversion and storage technologies, yet are often hindered by catalyst delamination and performance degradation during rapid and continuous bubble detachment under high current densities. Inspired by the rammed earth walling technique of ancient China, we constructed a porous network coupled with an island-shaped catalyst layer (CL) via a two-step electrodeposition strategy, achieving dual-interfacial mechanical optimization through network-island cooperativity. Experimental investigations revealed that the porous network mimicked the wooden reinforcing bar to provide continuous rigid support, realizing significant structural reinforcement at the substrate-CL interface (elevating critical adhesion force to 28.1 N) while effectively suppressing the agglomeration of active components via spatial confinement. Simultaneously, the nanosheet arrays embedded on the island-shaped structure disrupted the continuity of the solid–liquid-gas contact line, significantly lowering the CL-bubble interfacial adhesion force. This architectural feature facilitated the rapid release of bubbles at minimal volumes (reaching a detachment frequency of 28 s −1 ), preventing prolonged adhesion and mitigating mechanical damage to the substrate-CL interface during subsequent violent detachment. Coupled with the lowered energy barrier from phosphorus-induced electronic rearrangement, this architecture successfully overcomes the chronic activity-stability trade-off. When applied to the hydrogen evolution reaction (HER), the prepared electrode exhibited low overpotentials of 39, 120 and 191 mV at 100, 500 and 1000 mA cm −2 , respectively, while maintaining stable operation at 1000 mA cm −2 for over 143 h with negligible performance degradation after 40,000 CV cycles, which significantly outperformed the commercial Pt/C-loaded electrode, and underscored its shows potential for further development towards industrial-scale operation.