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

Abstract 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.