Daytime radiative cooling is an eco-friendly and passive cooling technology that operates without external energy input.Materials designed for this purpose are engineered to possess high reflectivity in the solar spec...Daytime radiative cooling is an eco-friendly and passive cooling technology that operates without external energy input.Materials designed for this purpose are engineered to possess high reflectivity in the solar spectrum and high emissivity within the atmospheric transmission window.Unlike broadbandemissive daytime radiative cooling materials,spectrally selective daytime radiative cooling(SSDRC)materials exhibit predominant mid-infrared emission in the atmospheric transmission window.This selective mid-infrared emission suppresses thermal radiation absorption beyond the atmospheric transmission window range,thereby improving the net cooling power of daytime radiative cooling.This review elucidates the fundamental characteristics of SSDRC materials,including their molecular structures,micro-and nanostructures,optical properties,and thermodynamic principles.It also provides a comprehensive overview of the design and fabrication of SSDRC materials in three typical forms,i.e.,fibrous materials,membranes,and particle coatings,highlighting their respective cooling mechanisms and performance.Furthermore,the practical applications of SSDRC in personal thermal management,outdoor building cooling,and energy harvesting are summarized.Finally,the challenges and prospects are discussed to guide researchers in advancing SSDRC materials.展开更多
基金supported by the National Natural Science Foundation of China(22308236)the China Postdoctoral Science Foundation(2023M742530,2024T170623)+2 种基金the Natural Science Foundation of the Jiangsu Higher Education Institutions of China(23KJA430012)the National Natural Science Foundation of Jiangsu Province,China(BK20230501)the Opening Project of the Key Laboratory of Bionic Engineering(Ministry of Education),Jilin University(KF2023002).
文摘Daytime radiative cooling is an eco-friendly and passive cooling technology that operates without external energy input.Materials designed for this purpose are engineered to possess high reflectivity in the solar spectrum and high emissivity within the atmospheric transmission window.Unlike broadbandemissive daytime radiative cooling materials,spectrally selective daytime radiative cooling(SSDRC)materials exhibit predominant mid-infrared emission in the atmospheric transmission window.This selective mid-infrared emission suppresses thermal radiation absorption beyond the atmospheric transmission window range,thereby improving the net cooling power of daytime radiative cooling.This review elucidates the fundamental characteristics of SSDRC materials,including their molecular structures,micro-and nanostructures,optical properties,and thermodynamic principles.It also provides a comprehensive overview of the design and fabrication of SSDRC materials in three typical forms,i.e.,fibrous materials,membranes,and particle coatings,highlighting their respective cooling mechanisms and performance.Furthermore,the practical applications of SSDRC in personal thermal management,outdoor building cooling,and energy harvesting are summarized.Finally,the challenges and prospects are discussed to guide researchers in advancing SSDRC materials.
