Near-infrared luminescence investigation of Cr~(4+) ions doped Li_2TiGeO_5

摘要

In this paper, the preparation of a series of Li_2TiGe_(1-x)Cr_xO_5 phosphors by high-temperature solid-state reaction is reported. The results of X-ray diffraction show that the doping of Cr~(4+) ions makes the lattice expand to a larger size. X-ray photoelectron spectroscopy analysis shows that the chromium ions in the sample are tetravalent, confirmed further by fluorescence spectroscopy. Under the excitation of 980 nm laser, the Cr~(4+) ions ~3T_2→~3A_2 radiates transition and emits light at 1300 nm. At the same time, the luminescence lifetime decreases with the increase in Cr~(4+) ions doping concentration. Li_2TiGe_(1-x)Cr_xO_5 phosphors have a broad application prospect in near-infrared LEDs.