UV Induced Thermoluminescence and Photoluminescence Studies of Sm3+Doped LaAlO3Phosphor

Abstract

Behavior is displayed by samarium-doped LaAlO3 phosphor which was synthesized by solid state reaction method. For the synthesis of LaAlO3 with variable concentration of Sm (0.2–2.5 mol%) phosphor was calcinated at 1000 °C and sintered at 1250 °C following intermediate grinding. Synthesized sample was characterized by X-ray diffraction analysis and crystallite size was calculated by Scherer's formula. From photoluminescence (PL) spectra of prepared phosphors show broad excitation peak at 250 nm and emission at 566, 600, and 608 nm is obtained. The phosphor is prepared by high temperature synthesis method. Two peaks are obtained in the thermoluminescence (TL) glow curve for lower concentration of Samarium. Single prominent peak is obtained with further increase in the concentration of dopant. It is characteristic yellow-orange emission for samarium ion. The excitation spectra of LaAlO3:Sm3+ phosphor mainly consists of the charge transfer band (CTB) of Sm3+ located in 220–340 nm centered at 250 nm. The present phosphors can act as single host for yellow-orange-red light emission in display devices. The CIE coordinates were calculated by spectrophotometric method using the spectral energy distribution of the LaAlO3 :Sm3+ sample. TL glow curve was recorded for variable concentration of dopant with fixed UV exposer time (20 min) and fixed heating rate (5 °C·s−1). TL glow curve shows broad peak and kinetic parameters are calculated by computerized glow curve deconvolution technique. It is suggested that from TL glow curve analysis prepared phosphor may be useful for TL dosimetric application for UV exposure.