Adaptive thermal regulation enabled by synergistic radiative cooling and phase change energy storage

Abstract

Radiative cooling is a promising passive strategy for temperature reduction without energy input, yet its application is often limited by overcooling and poor thermal stability under dynamic conditions. Here, a dual-layer adaptive cooling system integrating a radiative cooling (RA) layer with a phase change material (PCM) is developed to achieve continuous day-night thermal regulation. The electrospun PVDF-HFP membrane exhibits high solar reflectivity (>96.2%) and strong infrared emissivity (>95%), enabling efficient solar rejection and radiative heat dissipation, while the paraffin-based PCM provides a large latent heat of 158 J/g for thermal storage. The synergistic coupling of radiative cooling and phase-change heat storage enables dynamic temperature regulation across the diurnal cycle. Under solar irradiation, the RA layer suppresses heat gain and dissipates thermal energy, while the PCM absorbs excess heat, achieving sub-ambient cooling. At night, PCM releases stored heat to prevent overcooling and maintain thermal stability. Outdoor experiments demonstrate a maximum cooling of 9 °C below ambient and a delayed temperature rise of ∼45 min. To further evaluate its application potential, the system is investigated through building energy simulations and climate-based performance analysis. The results indicate reduced cooling-energy demand and carbon emissions across representative climate regions, with annual cooling-energy savings of up to 79.16 GJ. This work demonstrates an adaptive passive thermal-regulation strategy by integrating radiative cooling with phase-change thermal storage, providing a promising approach for energy-efficient thermal management.