Humidity-Responsive Actuator-Based Smart Personal Thermal Management Fabrics Achieved by Solar Thermal Heating and Sweat-Evaporation Cooling

Personal thermal management (PTM) fabrics with energy efficiency and cost-effectiveness have been rapidly developed in recent years, but it still remains challenging to maintain a favorable body temperature through one cloth in complex and dynamic environments. Herein, we propose an asymmetric fabric for self-adaptive thermal management with the aim of enhancing thermal comfort in outdoor environments. This fabric consists of an electrospun polyamide (PA) fabric and a PPy@MXene coating layer integrated into a kirigami structure. The PPy@MXene coating, a highly efficient photothermal conversion material, imparts the fabric with a substantial temperature increase of 44 °C under one sun of irradiation. By leveraging the hygroscopic expansion property of the PA fabric, the PPy@MXene/PA fabric exhibits high sensitivity as an actuator in response to humidity. After incorporating a kirigami-inspired design, the patterned fabric efficiently harnesses solar energy under weak sunlight irradiation for heating purposes and automatically opens channels for heat release when evaporating perspiration. This dynamic fabric demonstrates superior self-adaptivity compared to conventional static fabrics, thus, presenting great insights in developing smart PTM systems.