Spectral characteristics of green emitting phosphor Ca3Y2(Si3O9)2:Tb3+

A green emitting phosphor Ca3Y2(Si3O9)2:Tb3+ is synthesized by a high temperature solid state method, and initial materials are CaCO3 (A. R. ), Y2O3 (A. R. ), SiO2 (A. R. ) and Tb4O7(99. 99%). Phase formation is determined by X-ray diffraction (XRD) in a Bruker AXS D8 advanced automatic diffractometer (Bruker Co., German) with Ni-filtered Cu Kα1 radiation (λ=1. 540 6 nm). Steady time resolved luminescence spectra, and excitation and emission spectra are detected by a fluorescence spectrophotometer (Hitachi F-4600). Commission International de I'Eclairage (CIE) chromaticity coordinates of samples are measured by a PMS-80 spectra analysis system. The uniform diffraction patterns indicate that phase formation of Ca3Y2(Si3O9)2 is not influenced by a little amount of Tb3+. The excitation spectrum of Ca3Y2(Si3O9)2:Tb3+ presents an obvious 4f75d1 broadband absorption (200-300 nm) and a weak 4f→4f electronic transition absorption (300-500 nm) which corresponds to characteristic excitation of Tb3+, and the excitation peak locates at 236 nm. With different excitation wavelengths of 236 nm, 376 nm and 482 nm, the emission spectra show the same spectral distribution, and the peak locates at 544 nm (5D4→7F5). Temporal decay of Ca3Y2(Si3O9)2:Tb3+ as a function of Tb3+ concentration is investigated (λex=236 nm, λem=544 nm), and decay time of Ca3Y2(Si3O9)2:Tb3+ decreases with increasing Tb3+ concentration. However, the concentration quenching effect of Tb3+ in Ca3Y2(Si3O9)2:Tb3+ is not observed. ©, 2015, Board of Optronics Lasers. All right reserved.