Role of dopant concentration and starting reagents in the dosimetric performance of MgB4O7:Ce,Li

Abstract

MgB₄O₇:Ce,Li has emerged as a promising candidate for optically stimulated luminescence dosimetry (OSL) due to its high sensitivity to ionizing radiation, fast luminescence, and extended linear dose-response range. Despite its potential, variations in fading behavior and discrepancies in the linear dose-response region reported in the literature, compounded by a lack of direct sensitivity comparisons across studies, have raised questions regarding the reproducibility of the synthesis. These inconsistencies are believed to stem from differing synthesis methods. Our study integrates X-ray diffraction, synchrotron X-ray absorption spectroscopy, and comprehensive thermoluminescent (TL) and OSL analyses to demonstrate that the choice of starting reagents, and not the synthetic treatment per se, is critical for optimizing the dosimetric properties of MgB₄O₇:Ce,Li. Specifically, we find that using nitrates of Mg, Li, and Ce as precursors enhances the luminescent intensity compared to preparations from their respective oxides. This can be attributed to a more efficient incorporation of Ce³⁺ into the MgB₄O₇ lattice, contrary to the case of oxide precursors, where segregation of CeO₂ takes place. Our findings, alongside previous reports, pinpoint two pivotal factors in modulating the properties of MgB₄O₇:Ce,Li: sample preparation temperature and effective cerium concentration within the material.