Long-lasting and stable anti-fog coating combined with active and passive strategy
Cijian Zhang, Beitao Liu, Shengyuan Yu, Jiahui Li, Qian Liu, Shouhai Zhang, Xigao Jian, Zhihuan Weng
Abstract
There is an urgent need to design long-term effective anti-fog coatings to ensure the stabilization of uniform water films on hydrophilic surfaces, considering the impacts of interfacial strength, cyclic drying, and contaminants. Here, we propose an anti-fog strategy that leverages manipulating free volume and hydrogen bonding of hydrophilic networks through the twisted non-coplanar structures, synergized with photothermal effects, to enhance anti-fog efficiency. The introduction twisted non-coplanar structures of 1(2H)-phthalazinone not only significantly enhances the coating’s interfacial stability but also increases the molecular free volume, thereby substantially improving its moisture absorption capacity and extending the anti-fogging duration. The developed coating simultaneously achieves high transparency and efficient solar light absorption in the UV/NIR regions, effectively enhancing photothermal fog prevention and removal. The insights into anti-fog strategy promise to translate the structural free-volume benefits measured in laboratories into real-world applications for long-lasting and stable anti-fog coatings. Antifog coatings are of great interest, though it is challenging to balance interfacial strength, cyclic drying, and resistance to contaminants. Here the authors designed a coating using noncoplanar structures to enhance stability and anti-fogging efficiency.