Synthesis and characterization of thermoluminescent glass-ceramics Li2O-Al2O3-SiO2:CeO2

Vitroceramic powders of Li₂O-Al₂O₃-SiO₂ systems (LAS), doped with 1% (LAS:1Ce) and 10% (LAS:10Ce) molar of cerianite (CeO₂) were synthesized by means of the gelification technique of metal formates of aluminum and lithium, in the presence of tetraethoxy silane and CeO₂. The gels obtained were dried (120 °C, 2.5 h), calcined (480 °C, 5 h) and sinterized (1250 °C, 30 min). The sinterized samples were characterized by X-ray difraction (XRD), scanning electron microscopy (SEM) and microchemical analysis (EDS). There is evidence for a mixture of two phases of 64% β-spodumene (Li₂O-Al₂O₃-4SiO₂) and 36% β-eucryptite (Li₂O-Al₂O₃-2SiO₂). The LAS:1Ce system was enriched in aluminum, the LAS:10Ce system showed areas of heterogeneous composition; some regions with a shortage of CeO₂, while others zones with cerium cumulus. From the microscopy images it was found that CeO₂ acts as a densificant agent in LAS system, favoring the sintering in the host. The chemical route and the sintering processes utilized allow the production of samples exhibiting an acceptable linear correlation between total thermoluminescent emission intensity and the irradiation dose when the CeO₂ concentration is low (less than 1%), opening the possibility of using this kind of glass-ceramic in dosimetry.