Thermoluminescence, photoluminescence and EPR studies on Mn2+ activated yttrium aluminate (YAlO3) perovskite

• Published in: Journal of luminescence Vol. 132; no. 9; pp. 2409 - 2415
• Main Authors: Premkumar, H.B., Sunitha, D.V., Nagabhushana, H., Sharma, S.C., Nagabhushana, B.M., Shivakumara, C., Rao, J.L., Chakradhar, R.P.S.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 01.09.2012; Elsevier
• Subjects: Aluminates; Chemical synthesis; Combustion; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Electron paramagnetic resonance; Electron paramagnetic resonance and relaxation; EPR; Exact sciences and technology; Luminescence; Magnetic resonances and relaxations in condensed matter, mössbauer effect; Manganese; Nanocrystals and nanoparticles; Nanostructure; Optical properties and condensed-matter spectroscopy and other interactions of matter with particles and radiation; Optical properties of low-dimensional, mesoscopic, and nanoscale materials and structures; Other luminescence and radiative recombination; Phosphor; Photoluminescence; Physics; Thermoluminescence; X-ray diffraction; Yttrium; X-ray diffraction; Chemical synthesis; EPR; Phosphor; Luminescence; Scanning electron microscopy; Combustion synthesis; Particle size; Yttrium aluminate; Doping; Photoluminescence; Manganese additions; Perovskites; XRD; Line intensity; Gamma irradiation; Valence; Orthorhombic lattices; Nanopowder; Spherical particle; Electron paramagnetic resonance; Thermoluminescence
• ISSN: 0022-2313; 1872-7883
• DOI: 10.1016/j.jlumin.2012.04.019

Thermoluminescence (TL) measurements were carried out on undoped and Mn2+ doped (0.1mol%) yttrium aluminate (YAlO3) nanopowders using gamma irradiation in the dose range 1–5kGy. These phosphors have been prepared at furnace temperatures as low as 400°C by using the combustion route. Powder X-ray diffraction confirms the orthorhombic phase. SEM micrographs show that the powders are spherical in shape, porous with fused state and the size of the particles appeared to be in the range 50–150nm. Electron Paramagnetic Resonance (EPR) studies reveal that Mn ions occupy the yttrium site and the valency of manganese remains as Mn2+. The photoluminescence spectrum shows a typical orange-to-red emission at 595nm and suggests that Mn2+ ions are in strong crystalline environment. It is observed that TL intensity increases with gamma dose in both undoped and Mn doped samples. Four shouldered TL peaks at 126, 240, 288 and 350°C along with relatively resolved glow peak at 180°C were observed in undoped sample. However, the Mn doped samples show a shouldered peak at 115°C along with two well defined peaks at ∼215 and 275°C. It is observed that TL glow peaks were shifted in Mn doped samples. The kinetic parameters namely activation energy (E), order of kinetics (b), frequency factor (s) of undoped, and Mn doped samples were determined at different gamma doses using the Chens glow peak shape method and the results are discussed in detail. ► YAlO3:Mn2+—nanoparticles were prepared by the solution combustion method. ► EPR, TL, PL properties were reported. ► Kinetic trap parameters at different γ doses were reported. ► YAlO3:Mn2+ exposed to γ radiations showed promising TL characteristics.