Luminescence and dosimetric characteristics of nanocrystalline Al2O3:C synthesized by thermal plasma reactor

• Published in: Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms Beam interactions with materials and atoms, 2020-03, Vol.466, p.90-101
• Main Authors: Mandlik, Nandkumar T., Varma, V.B., Kulkarni, M.S., Bhatt, B.C., Sahare, P.D., Raut, Suyog A., Mathe, V.L., Bhoraskar, S.V., Dhole, S.D.
• Format: Article
• Language: English
• Subjects: Optically stimulated luminescence (OSL); Thermal plasma reactor; Thermoluminescence (TL); X-Ray Photoelectron Spectroscopy (XPS); γ- and α-phases of Nanocrystalline Al2O3:C
• ISSN: 0168-583X; 1872-9584
• DOI: 10.1016/j.nimb.2020.01.008

•Synthesis of nanocrystalline γ-Al2O3:C using thermal plasma reactor.•Phase change on changing the process parameters.•Phase change from γ- to α-phase on annealing at 1300 °C.•Deconvolution of TL glow curves using CGCD and trapping parameters.•Study of TL and OSL response curve for radiation dosimetry. Nanocrystalline Al2O3:C has been synthesized by thermal plasma method. The sample was annealed at 1300 °C in air and vacuum. XRD studies show phase change from γ-Al2O3:C to α-Al2O3:C. Average particle sizes estimated from XRD peaks and TEM images show increase in the particle size from ~30 nm to ~ 67 nm. The UV–visible spectrum of the as-synthesized Al2O3:C shows absorption peaks at 209 and 255 nm confirming the formation of F and F+ centers. XPS analysis reveals that the concentration of carbon impurity remains intact in Al2O3 lattice. The TL glow curves were fitted by CGCD method. The glow curve of as-synthesized Al2O3:C found to have six peaks and that of annealed sample have four peaks. The changes in the glow curve structures of the as-synthesized and annealed phosphor may be attributed to the phase change of the crystal structure and/or different kinds of defects formed on annealing in air/vacuum.