Synthesise, energy transfer and tunable emission properties of Ba2La2ZnW2O12:Sm3+ phosphors

In this work, we synthesize a series of Ba2La2ZnW2O12:Sm3+ (BLZWO:Sm3+) phosphors and research their crystal structure, morphology, and luminescence properties. The emission spectrum of host BLZWO with excitation at 370 nm can be observed in the range of 390–800 nm because of the W6+ - O2− transition in [WO6] group. BLZWO:Sm3+ phosphor with excitation at 370 nm emits yellow light with the emission spectrum in the range of 390–800 nm due to the W6+ - O2− transition in [WO6] group and the 4G5/2 → 6H9/2 transition of Sm3+ ion. BLZWO:Sm3+ phosphor excited at 408 nm emits red light and its emission spectrum in the range of 550–740 nm includes four narrow emission bands (550–580 nm, 580–625 nm, 625–685 nm, and 685–740 nm), which are derived from the 4G5/2 → 6H5/2, 6H7/2, 6H9/2, and 6H11/2 transitions of Sm3+ ion, respectively. We investigate the concentration-dependent excitation and emission spectra of samples. The lifetime of BLZWO:Sm3+ phosphor under excitation 408 nm decreases from 799.6 μs to 686.7 μs with increasing Sm3+ doping concentration. The energy transfer and luminous mechanism in BLZWO:Sm3+ phosphor are explained.