Thermodynamically regulated photothermal superhydrophobic membranes for anti-/de-icing

Uncontrolled ice accumulation poses severe risks to infrastructure and energy systems. Superhydrophobic surfaces can delay icing by reducing solid-liquid contact. However, under low-temperature impact conditions, rapid heterogeneous nucleation often occurs before droplet rebound, leading to the loss of liquid repellency. Here, an interfacial thermodynamic regulation strategy is proposed by constructing a photothermal superhydrophobic electrospun membrane, enabling synergistic control of ice nucleation and deicing under passive and active conditions. During electrospinning, filler migration toward the fiber surface and jet stretching generate semi-embedded protrusions and axial undulations. The resulting membrane exhibits a water contact angle of 157.4°, a sliding angle of 7.8°, and reduced contact angle hysteresis (13.7°). At −10 °C, the freezing delay time reaches 330.6 s, representing a 324.7% increase compared with the silicone rubber substrate. Heat transfer-phase change simulations further reveal inhibited heat transfer across the droplet-substrate interface and delayed upward propagation of the freezing front. Under 1 sun illumination, the membrane temperature rises to 38.5 °C, while the ice-melting time is reduced by 63.2% compared with the pristine SR/PS membrane. Importantly, photothermal heating delays nucleation beyond the droplet rebound timescale, enabling complete droplet detachment at −15 °C. Molecular dynamics simulations further reveal weakened interfacial water ordering, reduced solid-liquid interactions, and suppressed water mobility, confirming inhibited wetting and nucleation. This study reveals how interfacial structure, wettability regulation, and photothermal activation collectively govern ice nucleation and droplet dynamics, providing insights into the design of flexible anti-icing interfaces.