Novel Li1.0Nb0.6Ti0.5O3: Tb3+ ceramics with favorable luminescent and dielectric properties were prepared by solid-state reaction (SSR) method. The X-ray diffraction (XRD) results indicated that the Tb3+ ions were effectively dissolved into the "M-phase " matrix synthesized at 1000-1100 degrees C. The ceramic with a dense microstructure could be obtained at 1050 degrees C. The Li1.0Nb0.6Ti0.5O3: Tb3+ ceramics emitted green light at 550 nm and relatively strong red light at 660 nm under the excitation of 440 nm, which were located in the orange-red light region shown in the chromaticity diagram. The color coordinates were (0.5574, 0.4417) for the Li1.0Nb0.6Ti0.5O3: 2wt Tb3+ ceramic sintered at 1050 degrees C. The quantum efficiency of Li1.0Nb0.6Ti0.5O3: Tb3+ ceramic was 19, which was much higher than that of 9.6 for commercial red Y2O3: Eu3+ phosphors. Furthermore, for Li1.0Nb0.6Ti0.5O3: 2wtTb3+ ceramic synthesized at 1050 degrees C, the ideal dielectric properties with epsilon r of 66.263 and Q*f of 5582 GHz were obtained, which might be used as a potentially multifunctional ceramic applied in the fields of LED packaging to improve the lack of red light for blue LEDs combined with yellow phosphors.
展开▼
