EPR Study of UV and Gamma Irradiated Potassium Persulfate: A Sensitive Dosimeter

Abstract

EPR spectroscopic study of UV and gamma-irradiated potassium persulfate, K2S2O8, a dosimeter candidate in pellet form was reported. The importance of the radical structure that was studied in this work is the sensitivity against radiation from UV rays from Xenon lamp and gamma rays from Co-60 source, that is energies at eV to MeV. Powder EPR spectra reflect the anisotropy of both g and dipolar. The dose-response is supposed to be linear for UV radiation in the dose range under study and nearly linear for gamma rays from zero to 35 kGy dose. In addition, the radical structure is highly stable at room temperature and heat treatment up to 140 degrees C for artificial aging does not notably affect the intensity, and the original spectra are recovered when it cooled down to room temperature. Electrostatic repulsion between electrons of radical pair keeps the electrons in their locations, prevent recombination, and hence radical pair becomes stable for long. Thus, UV and gamma-irradiated potassium persulfate can be estimated as a valuable EPR dosimeter candidate material.