Hierarchically Programmed Meta‐Louver Fabric for Adaptive Personal Thermal Management

Abstract Smart clothing with adaptive personal thermal management functionality is highly desirable for wearing comfort and energy efficiency. However, due to the lack of common materials that can fabricate dynamic thermoregulation fabrics, translating the existing technologies to commercial applications remains challenging. Herein, leveraging an industrial textile manufacturing approach, a hierarchically programmed meta‐louver fabric with switchable modes for both hot and cold is developed. The efficacy of adaptive pore channels by manipulating the orientation of chiral knit loops to regulate water evaporation, as well as thermal convection and radiation, is experimentally demonstrated. In sharp contrast to current pore‐actuated smart textiles, the designed meta‐louver fabric gains its adaptive thermoregulation capacity directly from the multiscale textile structure engineering, ranging from the single‐helical‐fiber enabled yarn actuators to pre‐tension induced chiral‐helical knit loops. This strategy is shown to be also effective for other fiber materials, such as cotton, and thus provides a universal paradigm for a new family of metamaterials by engineering the interconnection of multiscale structures.