Effect of Eu Doping on the Radiophotoluminescence Properties of CaSiO3

To explore new radiophotoluminescence (RPL) materials, Eu-doped CaSiO 3 was synthesized by a solid-state reaction method, and its RPL behavior was evaluated from the viewpoint of radiation detection applications.X-ray diffraction (XRD) analysis confirmed that all samples were single-phase CaSiO 3 .After X-ray irradiation, a broad emission band attributed to the formation of Eu 2+ centers was observed, indicating that the Eu-doped CaSiO 3 host material exhibits distinct RPL behavior.The RPL sensitivity to radiation was highest at an Eu concentration of 0.1 mol%, with a linear dose response range from 0.18 Gy to at least 10 Gy.The Eu 2+ centers generated by irradiation were highly stable, showing only a 7% signal decrease after 20 min.Upon heat treatment, the photoluminescence (PL) spectra exhibited significant changes, accompanied by the emergence of a new broad emission band.Analysis revealed a decrease in the Eu 2+ emission and a corresponding increase in the Eu 3+ emission, suggesting a possible valence change from Eu 2+ to Eu 3+ .Furthermore, this broad emission becomes prominent at around 300 and above 400 and is also observed in undoped samples.The emission is considered to originate from defect centers formed within the host material during heat treatment.