Universal Sub-Nanoreactor Strategy for Synthesis of Yolk-Shell MoS₂ Supported Single Atom Electrocatalysts toward Robust Hydrogen Evolution Reaction

The coordination structure determines the electrocatalytic performances of single atom catalysts (SACs), while it remains a challenge to precisely regulate their spatial location and coordination environment. Herein, we report a universal sub-nanoreactor strategy for synthesis of yolk-shell MoS₂ supported single atom electrocatalysts with dual-anchored microenvironment of vacancy-enriched MoS₂ and intercalation carbon toward robust hydrogen-evolution reaction. Theoretical calculations reveal that the "E-Lock" and "E-Channel" are conducive to stabilize and activate metal single atoms. A group of SACs is subsequently produced with the assistance of sulfur vacancy and intercalation carbon in the yolk-shell sub-nanoreactor. The optimized C-Co-MoS₂ yields the lowest overpotential (η₁₀ =17 mV) compared with previously reported MoS₂ -based electrocatalysts to date, and also affords a 5-9 fold improvement in activity even comparing with those as-prepared single-anchored analogues. Theoretical results and in situ characterizations unveil its active center and durability. This work provides a universal pathway to design efficient catalysts for electro-refinery.