Synthesis, thermoluminescence and defect centres in Eu³⁺ doped Y₂O₃ nanophosphor for gamma dosimetry applications

Europium doped Y₂O₃ nanophosphors have been prepared by the solution combustion method. The prepared nanophosphors were characterized by powder x-ray diffraction (XRD). XRD revealed that the cubic phase with crystallite size in the range 25–37 nm formed. Surface morphology of the samples was studied by field emission scanning electron microscopy and the particles were observed as spherical in nature, having an average size ∼30 nm. The electron spin resonance spectrum of the irradiated nanophosphor exhibited a signal having peaks at g  =  2.1646 and 2.0035 which are attributed to $V^{-}$ and $O_2^{-}$ defect centers, respectively. Thermoluminescence (TL) emission showed a strong red (611 nm) emission at 417 K. The prominent TL glow (417 K) peak exhibited low fading, good reproducibility and linear dose response in the range 0.01–2.0 kGy. This behavior is favorable for TL dosimetry applications. The Y₂O₃:Eu³⁺ nanophosphor has prodigious potential as a dosimeter to be use for monitoring high dose ionizing radiation fields. (paper)