Recent advances in polymer-based radiative cooling material: Principle, designs and applications

Thermal regulation of buildings consumes around 40 ​% of global energy per year. With the growing energy crisis, the development of energy-saving materials and technology has emerged as a critical priority. Radiative cooling (RC) represents a promising avenue in the research of sustainable cooling technology, which dissipates excessive heat of objects into outer space by emitting thermal radiation without external energy input. Due to their excellent processability, cost-efficiency, plasticity and flexibility, organic polymeric materials have become one of the important candidates in the research of RC materials, meanwhile, the abundance of chemical bonds and functional groups within polymers ensures high emissivity at the atmospheric transparent window. Consequently, polymer-based radiative cooling materials have attracted tremendous attention. Through continuous efforts from scientists, significant contributions will be made to energy conservation and emission reduction, as well as improving energy utilization efficiency. This review presents an overview of the polymer-based radiative cooling materials, discusses the design principles for achieving high RC efficiency, summarizes the current broad application status of radiative cooling polymers in the fields of energy-saving building, personal thermal management and flexible electronics, and forecasts future development directions.