Effects of Pr concentration on the structural, mechanical and optical properties of KCl0.5Br0.5:Pr3+ crystals

Abstract

KCl0.5Br0.5:XPr3+ [X = 0.0 (pure KCl0.5Br0.5), 0.002, 0.004, 0.006, 0.008, 0.01, 0.02 and 0.04] crystals were successfully grown by Czockralski (Cz) pulling method and the structural, mechanical and optical properties of crystals were thoroughly investigated. X-ray diffraction (XRD) and X-ray photoelectron spectroscopic (XPS) studies indicated that the Pr ions have been incorporated into the KCl0.5Br0.5 host lattice and existed mainly as trivalent Pr. UV–Vis absorption spectra showed that the presence of peaks at 211, 227, 293, 457, 479, 494 and 601 nm. Hardness was found to increase with increasing of in Pr3+ concentration and indentation load, the hardness of the Pr doped crystals were larger than the un-doped crystal and the reverse indentation size effect was observed. The intensity of photoluminescence (PL) peaks was strongly depended on the Pr3+concentration. thermo-luminescence (TL) glow curves exhibited one peaks at 63–76 °C, indicating that one kind of trap existed in the crystals. The optimal luminous (both PL and TL) properties the KCl0.5Br0.5:XPr3+ crystals were obtained at X = 0.006. These results indicated that the KCl0.5Br0.5:Pr3+ crystals could be considered as a promising candidate for their use in optical and dosimetry applications.