Study of Radiophotoluminescence of Eu Doped CaSO4 Phosphor for Gamma Dosimetric Applications

V. K. Mahala; R. M. Sahani; S. G. Vaijapurkar

doi:10.14429/dsj.70.15042

V. K. Mahala DRDO-Defence Laboratory, Jodhpur - 342 011 https://orcid.org/0000-0001-6754-7121
R. M. Sahani DRDO-Defence Laboratory, Jodhpur - 342 011 https://orcid.org/0000-0002-4299-8898
S. G. Vaijapurkar Department of Physics, Jai Narain Vyas University, Jodhpur - 342 001 https://orcid.org/0000-0002-9998-3961

DOI: https://doi.org/10.14429/dsj.70.15042

Keywords: Dosimetry, Phosphor synthesis, Radiophotoluminescence

Abstract

CaSO₄:Eu phosphor is synthesised by acid distillation method with varying synthesis parameters for studying its Radiophotoluminescence (RPL) properties for gamma absorbed dose measurements. Five phosphor samples are prepared by varying quantity of solvent, distillation temperature and reaction time. XRD, SEM, particle size analysis and photoluminescence studies are carried out. The characterisation study shows polycrystalline luminescent particles of average size varying from 35 μm to 55 μm. Characteristic emission of Eu3+ is observed around 590, 615 and 620 nm at 242 nm excitation. Gamma dose response of maximum Eu3+ PL intensity sample is studied in the range 10 cGy to 1000 cGy using Co-60 source. Gamma radiation exposure induces conversion of Eu3+ to Eu2+ giving luminescence at 385 nm with 320 nm excitation. Repetitive measurements of gamma exposed samples are carried out and no significant fading is observed within one week of post-irradiation. The phosphor has the potential to be used for gamma dosimetry.