Cathodic corrosion as a facile and universal method for the preparation of supported metal single atoms

Top-down strategy has been generally adopted for preparation of metal single atom catalysts (SACs) due to the simplified synthetic process, metal economics, and scalability characteristics. Herein, we propose a general top-down route to convert metal nanoparticles into uniformly dispersed metal single atoms in mild electrochemical environment via a facile cathodic corrosion process. Within the synthetic process, Pt nanoparticles precursors are transformed into migrating Pt single atoms (Pt₁) driven by a high negative potential; and subsequently these mobile Pt atoms are trapped and stabilized by N coordination sites of N-doped carbon paper (NCP). The as-prepared Pt₁/NCP electrodes exhibit a superior catalytic activity toward hydrogen evolution reaction (HER) with a low overpotential of 0.022 V at 10 mA/cm² and a low Tafel slope of 28.5 mV/dec as well as a long-term durability. Notably, the proposed electrochemical atomic migration strategy shows a promising generality for fabricating other metal single atoms (e.g., Pd, Ir, Cu), which may open a new avenue for metallic SACs preparation.