Integrated passive cooling fabrics with bioinspired perspiration-wicking for outdoor personal thermal management

Incorporating passive cooling technologies into personal thermal management is an effective strategy to protect the human body from the exacerbations of global warming. However, for the increasingly harsh outdoor environment, a single gentle heat dissipation route can no longer meet the cooling needs of the human body. Here, we report a passive cooling fabric integrating radiation and sweat evaporation, which consists of a polyvinyl alcohol/tetraethyl silicate (PVA/TEOS) fibrous membrane and a thin thermoplastic polyurethane (TPU) fibrous membrane. The integrated passive cooling fabric (IPCF) exhibits intense solar radiation reflectivity (98.67%) and provides sufficient atmospheric window (AW) emissivity (98.63%) due to the precise design of photonic structures and the inherent optical properties of the matrix. Benefiting from the biological structures of hierarchical porosity and surface energy gradient, the directional perspiration-wicking of IPCF can promote rapid evaporative cooling and keep the skin dry. Outdoor experiments reveal that the IPCF realizes subambient cooling of ∼8.8 °C during midday and human skin cooling of ∼14.7 °C. In the case of simulating perspiration, rapid wick-evaporation further contributes to a cooling of ∼5.7 °C. The high efficiency and energy savings of IPCF provide tremendous advantages for outdoor personal thermal management applications.