Dopant-Controlled Lattice Oxygen Stability in Oxide-Derived Cu2O Surface

High-index Cu2O surfaces are promising catalysts for CO2 reduction (CO2RR), but their stability under reaction conditions remains a challenge. Here, ab initio molecular dynamics simulations are used to investigate lattice O retention in 3d transition metal (M)-doped oxide-derived high-index Cu2O(200) surfaces. Dopant-dependent O dynamics reveal that O mobility varies with both dopant identity and proximity. Time-resolved bond evolution indicates that early to mid 3d metals form stronger and more stable M-O bonds, while late transition metals exhibit weaker interactions. Consistently, higher O vacancy formation energies for early dopants confirm enhanced lattice O retention and structural stability, whereas late dopants promote O loss and surface reduction. These findings establish key structure-stability relationships and can provide guidance for designing durable Cu2O-based catalysts for CO2RR.