Low-cost and scalable sub-ambient radiative cooling porous films

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 center dot m(-2) was achieved in direct sunlight, achieving sub-ambient cooling of 4.2 degrees C. This work provides a unique solution for radiative cooling materials, which is expected to be implemented in practical applications of passive radiative cooling. (c) 2023 Society of Photo-Optical Instrumentation Engineers (SPIE)

Automated summary

Passive radiative cooling is a cost-effective and energy-efficient method, but its practical application is hindered by high costs and complex preparation processes. In this study, a simple phase separation method was used to prepare porous P-PVDF films for daytime radiative cooling. These films achieved high solar reflectivity of 95.6% and atmospheric window emissivity of 99.1%, leading to effective radiative cooling without the need for a metal reflective layer. The research provides a promising solution for practical implementation of passive radiative cooling.