Photochromism‐induced light scattering and photoswithing in Er doped (K,Na)NbO3 transparent ceramics

The (K0.5Na0.5)0.95Li0.05Nb0.95Bi0.05O3‐1mol% Er2O3 transparent ceramics were prepared by a pressureless sintering method. The fabricated transparent ceramics not only exhibit high optical transmittance (85.3%) due to dense microstructure (nanoscale size grains), but also show the photochromism‐induced light scattering and reversible upconversion (UC)‐switching properties by visible light irradiation. Upon 407 nm light irradiation, the optical transmittance intensity is significantly decreased, showing a strong light scattering (ΔAbs = 28.3%). The light scatting degree can be quantitatively reflected by Er3+ ion UC emission, and could be recovered to its initial optical transmittance based on photochromic reactions. Meanwhile, the transparent ceramic is found to maintain good energy storage properties with higher W (5.87 J/cm3) and Wrec (1.96 J/cm3) under a higher electric field of 260 kV/cm. These results suggest that Er3+ doped (K0.5Na0.5)NbO3 transparent ceramics are promising for the modulation of light scattering and the design of photoelectric multifunction devices.