Spectral Design\nof Nano-Cerates for Emerging Passive\nRadiative Cooling Technologies: Theory Boosts Experiments

Cerate nanoceramics have been recently considered to\nbe key materials\nfor radiative thermal management and enhanced solar reflectance. Herein,\nwe demonstrate by means of first-principles density functional theory\ncalculations how experimentally prepared La<sub>2</sub>Ce<sub>2</sub>O<sub>7</sub> and Al<sub>2</sub>Ce<sub>2</sub>O<sub>7</sub> materials\nwith defective fluorite structure exhibit superior temperature stability,\nstrong UV–vis/near-infrared reflectance, and tunable mid-infrared\nemissivity, thus representing excellent host matrices for doping-controlled\nchromatic and thermal properties. By means of phonon dispersion analysis,\nwe demonstrate how disorder and aluminum impurities induce locally\ndistorted chemical environments that can be exploited for achieving\nselective infrared emittance for passive radiative cooling devices.