Yongquan Liu, Sanwei Hao, Jun Yang, Jifei Zhang, Jia‐Long Wen, Wenfeng Ren, Bing Wang, Ling‐Ping Xiao, Changyou Shao, Run‐Cang Sun
Abstract Bio‐based alternatives to conventional photothermal hydrophobic materials are urgently required for sustainable ice mitigation. However, integrating robustness, efficient photothermal conversion, and environmental sustainability in one material remains challenging. Here, a bio‐based photothermal hydrophobic elastomer (LPAT) is synthesized via solvent‐free ring‐opening polymerization (ROP) of α‐lipoic acid (LA), with lignin (AL) incorporated as a renewable photothermal filler. Synergistic disulfide and hydrogen bonding endowed LPAT with high toughness (2.79 MJ·m −3 ) and fracture stress (4.45 MPa). Under simulated solar irradiation, LPAT exhibited rapid photothermal conversion, reaching 135 °C with a temperature rise of 112 °C. Hydrophobicity is retained after thermal and stretching cycles, with water contact angles above 116°. LPAT further demonstrated autonomous self‐healing with 80% efficiency and strong underwater adhesion. In deicing tests, it removed 3‐mm ice within 400 s and suppressed accretion under continuous freezing rain. Swelling resistance, reprocessability, and self‐cleaning enhanced its durability across repeated cycles. This work establishes a universal and sustainable platform for integrating high‐performance photothermal and hydrophobic properties, where efficient solar thermal management offers a fossil‐free alternative and facilitates the upcycling of solid waste into advanced energy materials.