Low-cost and scalable sub-ambient radiative cooling porous films
Bin Li, Boyu Cao, Ruichen Song, Yetao Zhong, Changhao Chen, Hengren Hu, Shigang Wu, Zhilin Xia
Abstract
Passive radiative cooling is an environmentally friendly and energy-free cooling method, but the practical application of radiative cooling materials is still limited by high costs and cumbersome preparation processes. Here, low-cost and chemically stable polyvinylidene fluoride (PVDF) was selected as the raw material and porous P-PVDF films for daytime radiative cooling were prepared by a simple phase separation method. A solar reflectivity of 95.6% and an atmospheric window emissivity of 99.1% were obtained, resulting in high-performance radiative cooling without a metal reflective layer. A cooling power of 69.43 W · m − 2 was achieved in direct sunlight, achieving sub-ambient cooling of 4.2°C. This work provides a unique solution for radiative cooling materials, which is expected to be implemented in practical applications of passive radiative cooling.