MXene aerogel-based phase change film for synergistic thermal management inspired by antifreeze beetles

To survive extreme weather, antifreeze beetles have a smart thermal management system, which relies on light absorption by the black surface and energy storage by antifreeze proteins. Inspired by the energy storage behavior of antifreeze proteins, we design a composite film, which is fabricated via impregnation of organic phase change material (PCM) in a surface-modified MXene/bacterial-cellulose aerogel. The resulting composite aerogel-based PCM film shows an increased loading capacity of organic PCM, increased phase change latent heat, and enhanced mechanical properties. Combining these thermal insulation and thermal energy storage properties, a submillimeter-thick film with an aerogel layer can maintain a comfortable temperature range for more than 800 s. This is more than double compared to the system without the films, and is a proof of concept for bioinspired photothermal-conversion/thermal-storage integration.