Up-conversion luminescence switching of (K0.5Na0.5)0.995Er0.005NbO3 ferroelectric ceramic based on photochromic reaction

Abstract Inorganic luminescence switching ferroelectrics based on photochromic reactions have great potential applications in optoelectronic devices. In this paper, (K0.5Na0.5)0.995Er0.005NbO3 ferroelectric ceramic is found to show a strong photochromic reaction by visible irradiation, and its color turns from initial milky white to gray. And up-conversion luminescence intensity can be greatly quenched by the light irradiation. The luminescence switching behavior upon photochromic reactions in (K0.5Na0.5)0.995Er0.005NbO3 ceramic as a function of irradiation wavelength and irradiation time has been investigated, and it is found that a high decrease of 79.47% is obtained after irradiation of 407-nm light for 4 min. The color and up-conversion luminescence of the irradiated ceramic can recover to its initial state by a 200 °C stimulus. However, the exciting 980-nm light has little effect on the up-conversion emission and photochromic reaction of the (K0.5Na0.5)0.995Er0.005NbO3 ceramic. These results demonstrate that the ceramic is promising in the applications such as luminescence switching and optical storage materials. In addition, the (K0.5Na0.5)0.995Er0.005NbO3 ceramic shows strong ferroelectric and piezoelectric properties.