Optical Behaviour and Defect-dependent Spectral Design of Cerium-based Nanoceramics for Emerging Passive Radiative Cooling Technologies

Cerate nanoceramics have been recently considered 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 along with tunable midinfrared emissivity, thus representing excellent host matrices for doping-controlled chromatic and thermal properties. By means of phonon dispersion analysis, we demonstrate how disorder and Al+3 impurity introduction induce locally distorted chemical environments that can be exploited for achieving selective infrared emittance for passive radiative cooling devices.