p-Band Modulation of Sn Single-Atom Catalysts via Curvature Engineering for Effective CO ₂ Reduction to HCOOH

RR performance. Significantly, electronic structure analysis reveals that the upshift of the Sn p-band center strengthens the (Sn p)-(O s) bonding interaction and modulates the (Sn p)-(O p) antibonding interaction, thereby optimizing the adsorption strength of *OCHO and improving catalytic activity. These findings clarify the role of orbital-level regulation in curvature-enhanced catalysis and provide theoretical guidance for the rational design of Sn-based single-atom catalysts through curvature engineering.