Abstract

Daytime radiative cooling technology offers a low-carbon, environmentally friendly, and nonpower-consuming approach to realize building energy conservation. It is important to design materials with high solar reflectivity and high infrared emissivity in atmospheric windows. Herein, a porous calcium silicate composite SiO2 aerogel water-borne coating with strong passive radiative cooling and high thermal insulation properties is proposed, which shows an exceptional solar reflectance of 94%, high sky window emissivity of 96%, and 0.0854 W/m·K thermal conductivity. On the SiO2/CaSiO3 radiative cooling coating (SiO2-CS-coating), a strategy is proposed to enhance the atmospheric window emissivity by lattice resonance, which is attributed to the eight-membered ring structure of porous calcium silicate, thereby increasing the atmospheric window emissivity. In the daytime test (solar irradiance 900W/m2, ambient temperature 43 °C, wind speed 0.53 m/s, humidity 25%), the temperature inside the box can achieve a cooling temperature of 13 °C lower than that of the environment, which is 30 °C, and the theoretical cooling power is 96 W/m2. Compared with the commercial white coating, SiO2-CS-coating can save 70 kW·h of electric energy in 1 month, and the energy consumption is reduced by 36%. The work provides a scalable, widely applicable radiative-cooling coating for building comfort, which can greatly reduce indoor temperatures and is suitable for building surfaces.

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.