Key points are not available for this paper at this time.
In response to the development concept of "carbon neutrality" and "carbon peak", it is critical to develop materials with high near-infrared (NIR) solar reflectivity and high emissivity in atmospheric transparency window (ATW, 8-13 μm) to advance zero energy consumption radiative cooling technology. To achieve the regulation of emission and reflection properties, a series of high-entropy rare earth stannate ceramics (HE-RE2Sn2O7: (Y0.2La0.2Nd0.2Eu0.2Gd0.2)2Sn2O7, (Y0.2La0.2Sm0.2Eu0.2Lu0.2)2Sn2O7, (Y0.2La0.2Gd0.2Yb0.2Lu0.2)2Sn2O7) with seriously lattice distortion were prepared using the solid phase reaction followed by pressureless sintering method for the first time. The lattice distortion is accomplished by introducing rare earth elements with different cation radius and masses. The as-synthesized HE-RE2Sn2O7 ceramics possess high ATW emissivity (91.38%~95.41%), high NIR solar reflectivity (92.74%~97.62%), low thermal conductivity (1.080~1.619 W·m-1·K-1) and excellent chemistry stability. On the one hand, the lattice distortion intensifies the asymmetry of the structural unit to cause a notable alteration in the electric dipole moment, ultimately enlarging the ATW emissivity. On the other hand, through selecting excitation-difficult elements, HE-RE2Sn2O7 with a wide band gap exhibits high NIR solar reflectivity. Hence, the multi-component design can effectively enhance the radiative cooling ability of HE-RE2Sn2O7 and provide a novel strategy for developing radiative cooling materials.
Chen et al. (Thu,) studied this question.