Structure, hardness, optical absorption, photoluminescence and thermoluminescence of Pr ions doped KCl single crystal

In this paper, KCl crystal doped with different Pr ions concentration were grown by the traditional Cz method. The structural, mechanical and optical properties of as-grown crystals were systematically studied by the experimental measurements. X-ray diffraction (XRD) results revealed that the K+ ions have been replaced by the Pr3+ ions. Hardness analysis displayed the hardness has been improved and both the normal and reverse indentation size effect (ISE) were observed. Absorption spectra confirmed six main peaks corresponding to the 3H4 ground state to the 5d1 level transition of the Pr3+ ions. The intense peak at 596 nm in the photoluminescence (PL) emission spectra corresponded to 3P2 -> 3H6 transition of the Pr3+ ions. The optimum doping concentration of Pr3+ in KCl crystal was found to be at x = 0.008, under the optimal concentration, the CIE coordinates of crystal were observed as x = 0.4390 and y = 0.49410. Three peaks centered at 51, 91 and 126 degrees C of KCl:0.008Pr crystal irradiated with X-ray were observed at the thermo-luminescence (TL) glow curve, the peak parameters were estimated based on the TL data, and the TL property under different X-ray dose has been studied.