Effect of Ce concentration on the structural, mechanical, electrical and optical properties of Ce-doped large-sized KCl0.5Br0.5 crystals

Abstract

Large-sized KCl0.5Br0.5:XCe3+ crystals doped with different Ce concentrations (with X = 0.0–0.05) were successfully grown by the melt (Czochralski) method. The structural, mechanical, electrical and optical properties were measured by carrying out X-ray diffraction (XRD), micro-hardness, direct current (DC)/alternating current (AC) electrical, optical absorption, photoluminescence (PL) and thermo-luminescence (TL) measurements. XRD analysis indicates the incorporation of Ce3+ ions into the KCl0.5Br0.5 crystal matrix. Hardness analysis shows that their values increase with the increase in crystal length and Ce3+ concentration. Electrical measurements indicate an increase of DC/AC electrical conductivity, dielectric loss factor and dielectric constant with the increase in Ce3+ concentration and temperature. Optical absorption spectra have shown that the excitation and emission peaks are strongly influenced by the Ce3+ concentration. The X-ray photoelectron spectroscopy (XPS) data-correlated luminescence (both PL and TL) have revealed that Ce3+ is the dominant state of cerium to be optimal for large area electronic devices and clinical dosimetry applications.