Thermoluminescence properties of Mn-doped CaYAl3O7 phosphor irradiated with ultra-violet, mega-voltage and gamma radiation

• The average particle size was found to be 19.9 nm of CaYAl3O7:Mn2+ phosphor synthesized by the combustion method.
• Two glow peaks were recorded in UV exposed sample. However with Gamma and MV irradiated sample a single glow peak was observed.
• TL intensity in the sample irradiated with UV is higher as compared to Gamma and MV.
• Glow peaks of the phosphor obeys second order kinetic has 0.637 eV activation energy and 9.9×107 S−1 frequency factor.
• Useful in radiation dosimetry as well as solid state lighting.

Low temperature combustion synthesis was employed for the preparation of CaYAl3O7(Mn2+) phosphor. X-Ray diffraction (XRD) patterns were recorded to confirm the phase formation. Estimated particle size was found to be ~19.9 nm by using the Debye Scherrer׳s formula. FTIR study confirms the formation of CaYAl3O7 compound, escape of nitrates and other organic products. Thermoluminescence (TL) glow curves of the prepared phosphor were recorded after exposing the sample with Ultra-violet (UV), 6-Mega-voltage (MV), 16-MV and Co-60(Cobalt-60, 1.25-MeV average gamma energy) radiation. Trapping parameters namely activation energy (E), order of kinetics (b) and frequency factor(s) of main peak, centered around 186 °C in the sample irradiated with UV source for 20 min, were determined using glow curve shape (Chen׳s) method. It has been observed that the TL peak intensity increases with increasing the exposure from UV source. Also with increases the energy of incident radiation a decrease in TL peak intensity were observed. This could be due to higher penetration power and less absorbance of incident beam in the phosphor material. Analysis suggests that possibility of utilizing this phosphor in futuristic low and high energy dosimetric applications as well as in solid state lighting devices.