Scalable self-adaptive radiative cooling film through VO2-based switchable core–shell particles

The development of highly efficient passive cooling technology has garnered significant attention. However, there is a mismatch between the cooling power of radiative cooling materials and actual cooling demand due to temperature variations. Therefore, there is a necessity for radiative cooling materials that can adjust to diverse weather conditions. In this study, a scalable self-adaptive radiative cooling film was proposed. By incorporating VO2-based core-shell nanoparticles into PE matrix, the radiative cooling film with self-adaptive ability has been achieved. The radiative properties of the film were predicted through the Mie theory and the Monte Carlo (MC) method. Two shell materials, BaF2 and ZnS, were considered. The effects of shell material, particle diameter D, inner/outer diameter ratio r/R, doping concentration fv, and film thickness t on the radiative properties of the film were evaluated. An optimal design of the film was carried out. The change in cooling power was calculated to evaluate the self-adaptive performance. The films achieved a maximum change in cooling power of 61.7 W/m2 (BaF2) and 60.7 W/m2 (ZnS). The energy-saving performance of the film was simulated by TRNSYS. This study provides a promising solution for scalable radiative cooling film with high self-adaptive cooling performance and durability.