Fluorescence Properties Of Silicate Oxyapatite Phosphors For White Led

White light emitting diode(WLED) is regarded as a green light source due to its small volum, low energy consumption, high brightness, long lifetime, and environmentally benign. The research for UV/NUV-excited single-phase phosphors with multi- color or full-color light to white LED lighting is now mainstream.In this paper, a series of silicate phosphors LSO(GSO):Eu(2+,3+), LSO:Eu(2+,3+),Ce3+,Tb3+ with apatite structure were synthesized by high temperature solid-state reaction. Their luminescent properties under UV/NUV excitation were investigated in detail. There are two valence europium ions in LSO(GSO):Eu(2+,3+) phosphor. Excited into Eu2+, the emission spectra are consisted of emission lines from transitions of 5D1(5D1,2)-7FJ and 5D0-7FJ. Excited into Eu2+, the lifetimes of 5D1(538 nm) is1.10 ms longer than that of 5D0(614.5 nm) 0.26 ms in. LSO:0.30Eu(2+,3+) phosphor.And the lifetimes of 5D1(539 nm) and5D2(468 nm) are 1.81 ms and 1.65 ms shorter than that of 5D0(614.5 nm) 1.82 ms in. GSO:0.30Eu(2+,3+) There are three luminescent centers of Eu3+in the host and their situations in crystallographic sites were surmised based on selective excitation spectrum.For Ce3+/Tb3+ co-doped samples, fixed Ce3+ concentration, chan ging the concentration of Tb3+, they exhibit both a blue emission fr om Ce3+ and a green emission from Tb3+ under ultraviolet light exc itation and the energy transfer process from partial Ce3+ to Tb3+ has been demonstrated to be a resonant type via a dipole–dipole mech anism. The emitting color varied from blue to green with the incre ase of Tb3+ concentration. For Ce3+/Eu3+ co-doped samples, the ener gy transfer occurs from Ce3+ to Tb3+ ions and the emitting color va ried from pink to red under ultraviolet light excitation with the incr ease of Eu3+ concentration. For Ce3+/Eu(2+,3+) co-doped samples, the emitting color varied from pink to candlelight color under ultraviole t light excitation with the increase of europium concentration. For Tb3+/Eu(2+,3+) co-doped samples, excited into 7F6-5D3 of Tb3+, the emiss ion spectra are consist of emission lines of Tb3+ and Eu3+, the emit ting color varied from candlelight color to near white light with the increase of Tb3+ concentration. For Ce3+/Tb3+/Eu(2+,3+) tri-doped sampl-es, the sample components of(0.02 Ce, 0.20 Tb, 0.20Eu),(0.01 Ce,0.10 Tb, 0.10Eu) and(0.01 Ce, 0.15 Tb, 0.10Eu) could emitting near white light.