A transparent radiative cooling emitter with multi-band spectral regulation for building energy saving

The radiative cooling technology has gained momentum. Maximizing the reflection of incident sunlight has been the primary approach to enhance radiative cooling properties. However, the fully reflection and opacity of the proposed radiative cooling materials significantly limits their application scope. In this study, a transparent radiative cooling emitter was fabricated by optimizing the concentration of SiX nanospheres embedded in PVDF matrix. The emitter has the capability of multi-band spectral regulation, and exhibits outstanding performance in terms of visible light transmission, near-infrared reflectance, and selective infrared emission. In the cooling experiment, the temperature of the emitter was up to 8.5 °C and 15.1 °C lower than with commercial insulation thermal films and common glass, respectively. The emitter prepared by easy process has potential for large-scale production.