Multicolor luminescence of PbWO4: RE3+ (Sm3+, Dy3+, Eu3+ and Tb3+) phosphor prepared via hydrothermal method

Abstract

Purely crystalline PbWO4: RE3+(Sm3+, Dy3+, Eu3+ and Tb3+) were prepared via hydrothermal method at 150 °C. X-ray diffraction studies of all the doped samples were in accordance with the tetragonal scheelite type structure of PbWO4 phase with no extra phase. Vibrational modes were also studied using FT-IR and Raman spectroscopy. All the excitation spectra of the samples showed strong and broad band with a maxima at around 320 nm due to charge transfer transitions within WO42−groups and series of sharp excitation peaks that can be assigned to typical intra-4f transitions of rare-earth ions. Under 320 nm UV light excitation, the photoluminescence spectra of RE3+ doped PbWO4 showed characteristic emission lines of the rare-earth dopant ions which can be attributed to the efficient charge transfer from WO42− groups to the rare-earth ions. From the CIE calculation, these prepared samples showed multi-color luminescence in the same host at a single excitation wavelength by altering the dopant ions in the host matrix.