Luminescent properties of Dy³⁺ - doped CaMgSi₂O₆ phosphor

Abstract

Photoluminescence (PL), mechanoluminescence (ML) and thermoluminescence (TL) studies of Dy³⁺-doped CaMgSi₂O₆ phosphor are reported in the present paper. The sample of CaMgSi₂O₆:Dy³⁺ was prepared by using a solid-state reaction method, where it was sintered at 1000 °C for 3 hour in a reducing atmosphere. The phosphor was characterized by using X-ray Diffraction (XRD), Energy dispersive X-ray (EDX) Spectroscopy, PL, TL, and ML measurement. From the X-ray diffraction pattern the phosphor was in a single-crystalline phase, and the average particle size of the CaMgSi₂O₆:Dy³⁺ phosphor was obtained as 44.15 nm from the peak corresponding to the (221) plane. The EDX spectroscopy confirmed the proper preparation of the sample. The afterglow of the sample exposed to ultraviolet (UV) radiation at 254 nm for 2 min could be seen for 30 min. The PL excitation peaks were found at 289 and 350 nm, and the CaMgSi₂O₆:Dy³⁺ phosphor showed three emission bands, with peaks at around 480 nm, 576 nm and 669 nm, respectively. From the TL glow curve, the activation energy was found to be 1.27 eV. The ML intensity increased linearly with increasing impact velocity of the piston used to deform the phosphor. The local piezoelectricity-induced electron bombardment model was shown to be able to interpret the ML emission well.