Dual-bioinspired MetaGels integrating heat buffering and radiative cooling for ultrahigh-power thermal management
摘要
Radiative cooling has been explored as a potential substitute for energy-intensive cooling technologies. Nevertheless, its maximum cooling power of 150 W m−2 is insufficient for outdoor electrical equipment. In response, phase change materials have been incorporated to enhance the cooling ability of radiative coolers. In this study, we present a novel MetaGel that mimics the hierarchical structure of mammalian skin and the adhesive properties of snails, consisting of a PVDF-HFP film and a phase change emulgel. The photonic film enables continuous sub-ambient cooling, and the emulgel buffers transient thermal shocks. Furthermore, the snail-inspired interface provides conformal contact with the substrate while minimizing interfacial thermal resistance. The MetaGel exhibits a solar reflectance of 99.2% and a mid-infrared emissivity of 96.5%, resulting in an exceptionally high average cooling power of 188.1 W m−2 over 8 h, as well as an instantaneous cooling power of 1162.3 W m−2. At a solar irradiance of 618 W m−2, the MetaGel demonstrates a mean temperature reduction of 22.2 °C for a power distribution box model, better than the 16.2 °C temperature reduction achieved with a PVDF-HFP film. The MetaGel shows promise as a reliable material for the long-term thermal management of outdoor electrical equipment under diverse climatic conditions.