Radiative Cooling Materials for High-Temperature Surfaces

Abstract

Efficient thermal management of high-temperature surfaces is increasingly important for industrial equipment, transportation systems, outdoor energy facilities, and high-power electronics, where persistent heat accumulation directly affects energy efficiency, operational reliability, and service lifetime. Although active cooling technologies remain dominant in practice, their high energy consumption and system complexity limit sustainable deployment. Meanwhile, conventional radiative cooling materials are mostly optimized to achieve passive sub-ambient cooling by reducing solar heat gain and enhancing infrared emission; however, their commonly used porous, polymeric, or optically scattering structures often possess low thermal conductivity, limited heat-transport pathways, and insufficient thermal stability, which can restrict heat extraction from continuously heated substrates and lead to insufficient cooling power and inadequate adaptability under fluctuating thermal environments. These limitations make it necessary to re-examine radiative cooling from the perspective of surface heat dissipation under sustained thermal load. In this review, recent advances in radiative cooling materials for high-temperature surfaces are introduced by focusing on three major challenges: reducing the energy penalty of cooling, enhancing heat-dissipation capacity for high-load surfaces, and coping with fluctuating thermal conditions. Correspondingly, broadband-emissive radiative cooling materials for passive cooling with reduced energy consumption, hybrid radiative cooling materials that couple radiation with additional heat-transfer pathways to deliver stronger cooling, and dynamically responsive materials for adaptive thermal regulation are summarized. Finally, the remaining challenges and future opportunities for practical deployment are discussed.