Pillar-Pore-Structured Nanophotonic Coating with Superior\nSolar and Thermal Modulation Abilities

There is a growing focus on the development\nof advanced materials\nto enhance energy efficiency in space heating and cooling, which accounts\nfor 13% of the annual consumption of global energy. Radiative cooling\nmaterials work in the wavelength span of middle-to-far-infrared light,\nespecially at 8–13 μm, which is effective in heat dissipation.\nHowever, their fixed emissivity results in unpleasant overcooling\nand consumes excessive energy in the winter. Adaptive cooling materials\ncan change the emissivity in response to temperature fluctuations,\nsolving the problem of overcooling. However, absorption of too much\nsolar heat in the daytime hinders effective dissipation of radiant\nheat, especially in summer. To address this issue, we propose a temperature-adaptive\nradiative cooling coating with a pillar pore structure that switches\nits thermal emissivity (8–13 μm) from 0.19 to 0.74 with\nincreasing temperature automatically. The coating also shows 85.9%\nsolar reflectance. The simulations demonstrate that our sample surpasses\nthe reported cool roof in terms of energy savings across different\nclimate zones, particularly those with substantial seasonal variations.