Substrate Lattice Parameter and Surface Wettability Govern Heterogeneous Ice Nucleation: A Molecular Dynamics Study

Heterogeneous ice nucleation kinetics on metal substrates are governed by the interplay of lattice parameters and surface wettability. Molecular dynamics simulations elucidate these mechanisms using a water nanodroplet on gold, platinum, and copper substrates with controlled wettability (water contact angles θ_WCA = 52°-112°). Key findings demonstrate: (1) Copper's superior lattice matching with ice crystal enhances the rate and temperature threshold of ice nucleation. (2) Hydrophilicity (θ_WCA = 52°) elevates temperature threshold of ice nucleation by 21 K on the copper substrate via strengthened interfacial water ordering. (3) Hydrophilic regimes favor hexagonal ice formation, while hydrophobic conditions promote cubic ice. (4) Precursor films delay ice nucleus formation and suppress ice growth. This study advances fundamental understanding of interfacial ice nucleation and provides design principles for anti-icing materials and atmospheric ice modeling.