One-Step Fabrication of a Carbon-Supported Ni Catalyst for Enhanced Hydrogen Evolution Reaction.

Supported metal catalysts are essential for efficient hydrogen production by water electrolysis, as carbon supports can improve electrical conductivity, enhance metal utilization, and facilitate catalytic charge transfer. However, conventional synthesis strategies often suffer from asynchronous formation of metal nanoparticles (NPs) and carbon phases, which hinders the synergistic construction of metal-carbon interfaces. Here, we report a one-step spark ablation in liquid (SAL) strategy for the rapid fabrication of carbon-supported Ni NPs. During spark discharge, Ni and C species are synchronously generated and integrated, forming intimate Ni-C interfaces. The defect-rich carbon structure stabilizes Ni NPs through strong metal-carbon interactions (SMSI), enabling a high production rate of up to 300 mg h-1. Detailed characterizations reveal that the strong interaction between Ni and carbon markedly modulates the electronic structure of Ni, thereby enhancing water dissociation kinetics and promoting alkaline hydrogen evolution. As a result, the obtained Ni@C catalyst delivers an overpotential of 378 mV at 500 mA cm-2, outperforming commercial Pt/C, and maintains stable operation for more than 300 h at 200 mA cm-2. This work provides an efficient one-step route for constructing supported metal catalysts and highlights the potential of SAL for scalable electrocatalyst fabrication.