Synthesis and thermoluminescence properties of rare earth-doped NaMgBO3 phosphor

Rare earth (Dy³⁺ and Sm³⁺)-doped sodium magnesium borate (NaMgBO₃) is synthesized by solution combustion synthesis method keeping their thermoluminescence properties in mind. The reaction produced very stable crystalline NaMgBO₃:RE (RE?=?Dy³⁺, Sm³⁺) phosphors. The phosphors are exposed to ⁶⁰Co gamma-ray radiations dose of varying rate from 5 to 25 Gy, and their TL characteristics with kinetic parameters are studied. NaMgBO₃:Dy³⁺ phosphor shows two peaks for lower doping concentration of Dy³⁺ while it reduced to single peak for the higher concentrations of activator Dy³⁺. NaMgBO₃:Dy³⁺ shows the major glow peak around 200 °C while NaMgBO₃:Sm³⁺ phosphors show two well-separated glow peaks at 200 and 332 °C respectively. The thermoluminescence intensity of these phosphors was compare with the commercially available TLD-100 (Harshaw) phosphor. The TL responses for gamma-ray radiations dose were found to be linear from 5 to 25 Gy for both phosphors while the fading in each case is calculated for the tenure of 45 days.