Synthesis, optical and thermal properties of novel Tb3+ doped RbCaF3 fluoroperovskite phosphors

Phosphors of pure and Tb3+ doped RbCaF3 were synthesized by the conventional solid state reaction method. The structure and morphology of the phosphors were characterized, using powder XRD and field emission scanning electron microscopy (FE-SEM). The presence of the functional groups was confirmed by using Fourier Transform Infra Red (FT-IR) spectral analysis. The absorption bands of Tb3+ ions with peaks at 220, 266 and 363 nm were observed in the RbCaF3: Tb3+. The sharp emission was observed at 539 nm for Tb3+ doped RbCaF3 phosphors with CIE chromaticity coordinates (x = 0.233, y = 0.337). The luminescence quantum efficiency was determined and the decay profile was obtained and analyzed. The thermoluminescence (TL) glow curve shows four peaks at 79, 115, 207 and 310 °C. Of these four peaks, the two which are at higher temperature can be considered for the dosimetric applications. The experimental results demonstrated that the Tb3+ doped RbCaF3 green emitting phosphor is a potential candidate for white light emitting diodes (WLEDs) pumped by UV chip.