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.