Effective radiative cooling with ZrO2/PDMS reflective coating

Radiative cooling (RC) has attracted growing attention in recent years since it is a terrestrial object that radiates heat to outer space through the atmospheric window while maintaining zero-energy consumption. It emits or absorbs radiation only in the atmospheric window (8–13 μm) and suppress it beyond this band. In this paper, we present a radiative cooling coating composed of a zirconia (ZrO2) embedded polydimethylsiloxane (PDMS) hybrid ZrO2/PDMS coating. The influences on radiative cooling by particle sizes and volume fractions and film thicknesses are evaluated via Mie scatter theory combined with Monte Carlo ray-tracing method. The ZrO2/PDMS coatingdis plays a surface temperature drop 10.9 °C at the solar intensity of 895 W/m2, much better than the commercial white paint (4.4 °C). As it performs efficiently above ambient temperature and is easy to manufacture this coating, this coating may have some promising future for potential large-scale application of radiative cooling technology on energy-saving buildings. •Mie scatter theory combined with Monte Carlo simulation is used to analyse the optical properties of particles (ZrO2) embedded into polymers (PDMS).•Preparation of coating is simple.•Reflectivity of coating (300–1350 nm) is about 93.55% and emissivity (2–25 μm) reaches 92.25%.•Temperature drops of 10.9 °C is achieved under the solar intensity of about 895 W/m2.•Temperature inside the house model with the coating is about 4.2 °C lower than that of commercial paints.