Spectral Design of Nano-Cerates for Emerging Passive Radiative Cooling Technologies: Theory Boosts Experiments

Cerate nanoceramics have been recently considered to be key materials for radiative thermal management and enhanced solar reflectance. Herein, we demonstrate by means of first-principles density functional theory calculations how experimentally prepared La2Ce2O7 and Al2Ce2O7 materials with defective fluorite structure exhibit superior temperature stability, strong UV-vis/near-infrared reflectance, and tunable mid-infrared emissivity, thus representing excellent host matrices for doping-controlled chromatic and thermal properties. By means of phonon dispersion analysis, we demonstrate how disorder and aluminum impurities induce locally distorted chemical environments that can be exploited for achieving selective infrared emittance for passive radiative cooling devices.