Ambient‐Dried Phase‐Change Functionalized Thermal Insulation Materials with Latent Heat Charging/Discharging Capacities and Superior Temperature‐Adaptive Thermal Regulation Performance

Abstract Distinct from conventional passive radiative coolers, newly developed thermally insulating radiative coolers demonstrating superior thermal regulation performance by additionally suppressing heat conduction from the hot environment into the internal house have emerged as an enticing solution for reducing the building energy consumption. Although great efforts are made to optimize the thermal regulation performance of insulating coolers, the strategies developed almost all involve sophisticated fabrication processes concerning supercritical drying or freeze‐drying, and balancing excellent radiative cooling and insulation functionalities with scalable production continues to pose challenges. Herein, a novel phase‐change‐enhanced thermal insulation cooler is fabricated using a facile ambient drying technique. Benefiting from the latent heat storage and release characteristics of the phase change materials (PCMs), the resulting composites present additional advantages for thermal regulation by effectively delaying heat propagation, solving the issue of nighttime supercooling induced by the high infrared emissivity of the state‐of‐the‐art radiative coolers. In field tests, the cooler achieves a maximum temperature drop of ≈19 °C in the daytime and a temperature rise of ≈2.6 °C at night, effectively reducing the indoor temperature variations. This work provides insight into the scalable fabrication of a phase‐change‐enhanced insulating cooler with all‐day temperature‐adaptive thermal regulation capacity.