Influence of the synthesis pathway upon the thermoluminescent response of gadolinium aluminate matrix phosphors

Abstract

The phosphors endowed with a glow curve have a peak much more intense than the others, sensitization to low doses, and a linear relationship between the thermoluminescent response and the dose, which are in demand in the dosimetry market. The gadolinium aluminate has been successfully used as a host lattice of phosphors with luminescent properties. Principally, the luminescent response of the said matrix has been improved by doping with rare earth ions. The thermoluminescent signal depends on the synthesis route because the defect density of a crystal is closely connected to the production pathway that the material went through. Therefore, a crucial step in sensitizing a phosphor is selecting a synthesis route that enhances the efficiency of its thermoluminescent mechanisms. The research herein focused on synthesizing phosphors composed of gadolinium aluminate with no dopant and doped with two molar percent of dysprosium, using two different routes. Among the two synthesis pathways, it was determined to be the most suitable for enhancing the thermoluminescent response of the aforementioned phosphors. The methods employed were reverse coprecipitation and the modified citrate precursor. The phosphors obtained by the reverse coprecipitation method showed the most sensitive thermoluminescent signal. Mainly, the phosphor activated with the dysprosium ion produced the most intense signal, suggesting an improvement in the thermoluminescent mechanisms due to the dopant insertion.