Single Crystal Growth of BaCl2 & BaCl2:Eu2+ and Their Optical Characterisation for Ionizante Gamma Radiation Detection

Abstract

Single Crystals of Orthorhombic BaCl2 and BaCl2:Eu2+ were grown using a home-made Czochralski system by extracting from the melt in a carbon crucible, and argon atmospheric pressure upon using BaCl2 and EuCl2 powders of 99.995% and 99.99% purity, respectively. The results corresponding to XRD analysis for the grown crystals confirm the phase purity and the orthorhombic structural phuse of the grown BaCl2 and BaCl2:Eu2+ crystals. The ICP model Optima-2100 was also used to measure Eu2+ ion concentration. The fluorescence emission, excitation and absorption spectra were obtained using a Cary-Eclipse WinFLR fluorometer and a Cary17D spectrophotometer. The prepared crystaling samples found to be colorless and transparent with no observed cleavage. Therefore, excluding OH-, oxygen and carbon contaminations from the growth system was to some extent a successful result, which is indicating that a transmittance coefficient of about 80% is considered as a suitable optical feature of the BaCl2 single crystal. The study of photoluminescence spectroscopy of BaCl2 single crystals, with and without Eu2+ ion impurity, showed that the occurrence of the high intensity and low band width (FWHM~30nm) PL-band of BaCl2:Eu2+ sample at 400nm are indicating an increase of the optical efficiency compared with and without applying the impurity. As a result, it could be observed that the doped crystals with europium can be served as a luminescence material for radiation detectors.

Keywords

• crystal growth
• optical properties
• ionizing radiation
• barium chloride