Structures, Dielectric Properties and Luminescence Properties of Nb Doped Li2TiO3 Solid Solution Ceramics

In this article, the low-firing Li2+xNb3xTi1-4xO3(x = 0.01, 0.02, 0.04, 0.06) ceramics with monoclinic structure have been obtained by the traditional solid solution method and their microwave dielectric properties were investigated in detail. The ceramics were finely densified at lower temperatures around 1100 °C and demonstrated favorable dielectric performances including relatively low permittivities (εr) ranging from 19 to 24, high Q×f values up to 60,000 GHz (fres = 7.89GHz) and small temperature coefficients of the resonate frequency (for x = 0.02, τf = 10.4 ppm/ °C; x = 0.06, τf = -11.5 ppm/ °C). Furthermore, the ceramics could be densified at around 900°C with adding low-amount of B2O3. Especially, the 1wt.% B2O3-doped Li2+xNb3xTi1-4xO3 (x = 0.06) ceramics was sintered well-densified at 900°C and presented good microwave dielectric properties with εr ∼ 22.2, Q×f ∼ 44,000 GHz. In addition, these ceramics have luminescence properties, which indicated that the ceramics would be applied in LTCC and/or luminescence applications as new luminescence LTCC (low temperature co-fired ceramics) materials.