Synthesis and photoluminescence properties of high-efficiency BaGd_2Si_3O_(10):Eu~(3+) red phosphors for WLEDs and display device applications

摘要

The present paper reported the spectroscopic behavior and thermal stability of Eu3+ activated BaGd2Si3O10 phosphors synthesized by high temperature solid state reaction. The X-ray diffraction (XRD) patterns revealed that as-prepared BaGd2Si3O10:xEu(3+) phosphors consisted of single phase monoclinic structure. Under the excitation of 395nm, Eu3+ ions showed five emission peaks around 578, 589, 613, 654 and 702nm corresponding to the (D0F0)-D-5-F-7, (D0F1)-D-5-F-7, (D0F2)-D-5-F-7, (D0F3)-D-5-F-7 and (D0F4)-D-5-F-7 transitions, respectively. The value was calculated to be 6.68, which indicated that concentration quenching occurred due to dipole-dipole interactions. The critical distance (R-c) between activator ions was found to be 11.2 angstrom. Decay curve measurements were made to find excited state lifetime of Eu3+ ions. The dominant emission color of as-prepared phosphors was obtained by using CIE 1931 color chromaticity diagram. Further, thermal stability and activation energy for thermal quenching were also estimated for the optimal concentration phosphor to claim its applicability for near-UV based WLEDs.