Recent advances in passive daytime radiative cooling coatings: Fundamentals, strategies and prospects

Passive daytime radiative cooling (PDRC) is an effective cooling method that operates without the need for external energy input, possessing the potential to reduce energy demand and mitigate the effects of global warming. In the past few decades, researchers have continuously explored and proposed a variety of multifunctional PDRC. In this regard, coating is a versatile and effective means to implement the PDRC technology. Currently, manufacturing PDRC coatings using a roll-to-roll process has made certain progress, and the way to prepare the coatings with lasting performance and achieve large-scale production has become the focus of current research. Firstly, this paper analyses the basic principles of PDRC. Then, it reviews the recent progress of PDRC coatings from the aspects of material design and application, and systematically analyses the advantages and potentials of PDRC coatings in a variety of fields, with particular attention to the feasibility of PDRC coatings promotion and application. Finally, to further promote the commercialization process of PDRC, the paper presents challenges that need to be addressed and long-term future directions for development.