Bioinspired Light-Scattering Structures for Passive Daytime Radiative Cooling

With the intensifying effects of global warming and the growing demand for cooling, passive daytime radiative cooling (PDRC) has emerged as a promising and sustainable solution, in which PDRC reflects solar radiation and dissipates heat through the 8-13 µm atmospheric window without energy consumption, offering a viable approach to reducing electricity usage for cooling. A key factor in enhancing PDRC performance is the use of bioinspired light-scattering structures, which effectively regulate solar reflection and long-wave infrared emission. This review systematically outlines the design principles and regulation strategies of scattering structures in radiative cooling materials, focusing on two primary systems: scattering particles and porous architecture. It examines their individual contributions and synergistic effects in improving both solar reflectivity and infrared emissivity. Special emphasis is placed on bioinspired structural designs, exploring how nature-inspired patterns can enhance spectral selectivity and scattering efficiency. The review also summarizes representative applications in building energy conservation, photovoltaic thermal management, wearable electronics, and agricultural environments regulation. Finally, it discusses current technical challenges and offers perspectives on future developments in structural design and scalable fabrication methods, aiming to provide both theoretical insights and practical guidance for the advancement of radiative cooling technologies.