Hierarchically porous polymer coatings for highly efficient passive daytime radiative cooling

We present a simple, inexpensive, and scalable phase inversion–based method for fabricating hierarchically porous poly(vinylidene fluoride-co-hexafluoropropene) [P(VdF-HFP)HP] coatings with excellent PDRC capability. High, substrate-independent hemispherical solar reflectances (0.96 ± 0.03) and long-wave infrared emittances (0.97 ± 0.02) allow for subambient temperature drops of ~6°C and cooling powers of ~96 watts per square meter (W m–2) under solar intensities of 890 and 750 W m–2, respectively. The performance equals or surpasses those of state-of-the-art PDRC designs, and the technique offers a paint-like simplicity.

Source: ScienceNOW - October 18, 2018 Category: Science Authors: Mandal, J., Fu, Y., Overvig, A. C., Jia, M., Sun, K., Shi, N. N., Zhou, H., Xiao, X., Yu, N., Yang, Y. Tags: Physics, Applied, Materials Science reports Source Type: news