Thermoluminescence properties of rare earth doped lithium magnesium borate phosphors

• Published in: Journal of luminescence 2011-12, Vol.131 (12), p.2492-2498
• Main Authors: Anishia, S.R., Jose, M.T., Annalakshmi, O., Ramasamy, V.
• Format: Article
• Language: English
• Subjects: Borates; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Dosimeters; Dosimetry; Emission; Exact sciences and technology; Lithium; Magnesium; Optical properties and condensed-matter spectroscopy and other interactions of matter with particles and radiation; Other luminescence and radiative recombination; Phosphor; Phosphors; Photoluminescence; Physics; Rare earth metals; Thermoluminescence
• ISSN: 0022-2313; 1872-7883
• DOI: 10.1016/j.jlumin.2011.06.019

This paper reports the thermoluminescence (TL) properties of rare earth doped lithium magnesium borate (LMB) polycrystalline phosphor. LMB phosphor has been prepared by high temperature solid state diffusion method. Among all the rare earth doped LMB phosphors, terbium doped material has shown maximum TL sensitivity with a broad dosimetric glow peak at 240 °C. near the tissue equivalent TL phosphor with terbium dopant has about four times the TL sensitivity of TLD-100. The main dosimetric properties such as glow curve stability, TL response versus absorbed dose, post-irradiation storage stability, and reusability are investigated. This TL material has a linear dose response up to 10 3 Gy, negligible storage fading and a simple annealing procedure for reuse. The TL emission spectra of LMB:Tb 3+ showed broad green emission at 544 nm, which merged with host emission. The characteristic Tb 3+ emissions are seen in the photoluminescence (PL) spectra. ► New tissue equivalent thermoluminescence material based on lithium magnesium borate is synthesized through solid state method. ► Terbium doped phosphor has shown a broad dosimetric glow peak at 240 °C with TL sensitivity four times that of TLD-100. ► It exhibited near linear TL response up to the saturation dose of 10 3 Gy. ► Simple annealing procedure keeps the glow curve structure and sensitivity steady for many cycles. ► LMB:Tb 3+ phosphor can be a very promising TL dosimetry material for gamma as well as neutrons.