Up-conversion luminescence and electric properties of Tm3+/Yb3+ co-doped (0.94Na0.5Bi0.5TiO3–0.06BaTiO3) ceramics

Abstract

The Tm 3? /Yb 3? co-doped 0.94Na 0.5 Bi 0.5 TiO 3 -0.06BaTiO 3 (NBT-BT:Tm 3? /Yb 3? ) ceramics were synthesized by solid-state reaction and characterized by X-ray diffraction, SEM, luminescence, dielectric, ferroelectric and piezoelectric measurements. The XRD and SEM showed that all the ceramics were the single phase with perovskite structure. The up-conversion emissions located at 490 nm (blue, 1 G 4 ? 3 H 6 ), 551 nm (green, 3 F 3 ? 3 H 6 ) and 665, 699 nm (red, 1 G 4 ? 3 F 4 , 3 F 2 ? 3 H 6 ). Furthermore, two-photon absorption process would dominate the optimized UC emission intensity in NBT-BT:0.005Tm 3? / 0.02Yb 3? samples. Moreover, up-conversion temperature sensitivity was detected at NBT-BT:0.005Tm 3? /0.02Yb 3? samples with value of 0.068 K -1 related to the intensity ratio of I 669 and I 665 emissions. In addition, relatively good dielectric properties and ferroelectric properties (Pr = 60 l/cm 2 and Ec = 42 kV) were obtained in NBT-BT:0.005Tm 3? /0.005Yb 3? . Curie temperature enhanced with large amount of Yb 3? ions increasing (y [ 0.02). As multi-functional material, NBT-BT:Tm 3? /Yb 3? ceramics may be useful in high temperature electro-optical devices.