A double perovskite Ca2MgWO6:Bi3+ yellow-emitting phosphor: Synthesis and luminescence properties

Novel double perovskite Ca2MgWO6:Bi3+ (CMW:Bi3+) yellow-emitting phosphor is synthesized by solid-state reaction method in air. Host Ca2MgWO6 with excitation 297 nm emits blue light and the chromaticity coordinate is (0.169, 0.160). The spectroscopic properties of CMW:Bi3+ phosphor are explained on the basis of the Bi3+ (6s(2))-W6+ (5d(0)) metal-to-metal charge transfer (MMCT) transition. CMW:Bi(3+)phosphor with excitation 338 nm shows yellow light and the chromaticity coordinate is (0.383, 0.477). Broad emission band peaking at similar to 550 nm of CMW:Bi(3+)phosphor is observed in the range of 400-780 nm due to the D -> S-1(0) radiative decay and the P-3(1,0) -> S-1(0) transitions of Bi3+ ion. Monitored at 550 nm, excitation spectrum of CMW:Bi3+ phosphor including a strong excitation peak at similar to 338 nm covers the region from 200 to 400 nm owing to the Bi3+ -> W6+ MMCT transition and the S-1(0) -> P-3(1) transition of Bi3+ ion. The optimal Bi3+ ion actual content is similar to 0.38 mol%. Emission spectra of CMW:Bi3+ phosphor with excitation 338 nm shows blue-shift with increasing temperature from 50 to 300 K owing to the influence of temperature to electron transfer. The possible luminous mechanism of CMW:Bi3+ phosphor is analyzed by energy level diagram of Bi3+ ion in solid including d(0) cation. (C) 2016 Elsevier B.V. All rights reserved.