Ca3La2W2O12:aTm3+, bDy3+: A potential tunable single-phased white-emitting phosphor under near-ultraviolet light excitation

Many Dy3+-Tm3+ double ion doped Ca3La2W2O12 phosphors were prepared using the high-temperature solid-state reaction. The microstructure, luminescence performance, quantum yield, and fluorescence lifetime of Ca3La2W2O12:aTm(3+), bDy(3+) phosphors were systematically studied using XRD, fluorescence spectrometer, and SEM. The luminous color of the samples was visually displayed using color coordinates. The emission spectra showed that Ca3La2W2O12:0.08 Tm3+ phosphor excited at 353 nm could generate D-1(2) -> F-3(4) energy level transition and emitting blue light. The concentration quenching point of Tm3+ ions, a = 0.08 mol Ca3La2W2O12:0.06Dy(3+) phosphor excited at 354 nm can generate blue light from F-2(9) -> H-6(15/2) (e)nergy level transition and yellow light from F-2(9) -> H-6(13/2) energy level transition of Dy3+ ion. The concentration quenching point of Dy3+ ions, b = 0.06 mol. By adjusting the doping ratio of Tm3+ and Dy3+ ions to control the relative intensity of the emission spectra, the Ca3La2W2O12 :0.08 Tm3+,0.12Dy(3+) white phosphor is finally obtained, and its color coordinates is (0.338, 0.326) very close to standard white light (0.333, 0.333). The change rule of fluorescence spectra and fluorescence lifetime proved that there was an effective energy transfer of Tm3+-Dy3+ The energy transfer mechanism is electric quadrupole-electric quadrupole interaction. When the Dy3+ ion doping amount b = 0.12 mol, the energy transfer efficiency reached 72.50%. The quantum yield of Ca3La2W2O12:0.08 Tm3+, 0.06Dy(3+) phosphor is 48.14%. The results show that this series of phosphors have potential development and application prospects.

Automated summary

In this study, Dy3+-Tm3+ double ion doped Ca3La2W2O12 phosphors were prepared using high-temperature solid-state reaction. The microstructure, luminescence performance, quantum yield, and fluorescence lifetime of the phosphors were systematically studied. By adjusting the doping ratio of Tm3+ and Dy3+ ions, a white phosphor was obtained with efficient energy transfer between the ions.