All-Day Sustainable Energy-Free Antifrosting Surface with Interfacial and Zonal Thermal Management

Frost formation poses significant threats and economic losses in many fields. Photothermal superhydrophobic defrosting (PSD) surfaces have garnered considerable interest; however, the frost layer on the surface hinders the effectiveness of photothermal performance. Here, a zonal thermal management (ZTM) strategy is demonstrated to maximize the performance of PSD surfaces that are composed of hierarchical multilayer structures on the zonal millimeter-scale arrays. The peaks with a low solid–liquid area act as low-adhesion zones, and the valleys serve as effective photothermal heating zones. The heat spreader can rapidly transfer heat from heating valleys to the frost-covered peaks, while the thermal insulation layer minimizes heat loss to the cold substrate. Even under low temperatures and low solar intensities, the ZTM strategy prevents the surface from being completely covered by frost and enables photothermal heating to remove frost efficiently. The first demonstration of the ZTM strategy provides insights into designing efficient all-day antifrosting surfaces.