Introduction:

in the search for new materials useful as thermoluminescent dosimeters (TL) alumina (α-Al2O3) has acquired great attention. The α-Al2O3 has a sensitivity TL that is perceptível to the concentrations of impurities and to the thermal conditions of the growth of its crystals, so finding new variations of the material will allow to increase its TL response.

Objective:

analyze the brightness curves of pure alumina matrices sintered under different calcination conditions and doped with cerium at a concentration of 0.1 % p/p (Al2O3:Ce), using the asymmetric logistic function, to calculate its thermoluminescent kinetic parameters and explain the behavior of the material.

Materials and methods:

boehmite alumina powder was used to prepare pure sintered samples of under different calcination conditions (NALO and ALO). The cerium was introduced by wet impregnation using cerium hexahydrate nitrate. The structural analysis of the matrices was carried out by X-ray diffraction. The TL reading was performed in a TLD 4500.

Results:

the deconvolution obtained in the brightness curves for the ALO and NALO groups evidences the presence of three and four TL signals respectively, and of six TL signals in the sample Al2O3:Ce.

Conclusion:

the applied heat treatments introduced a substantial change in the brightness curve of the material and its TL kinetics, in terms of the number of traps and the initial amount of charge carriers trapped. The introduction of cerium impurities produced a fundamental modification in the brightness curve of the alumina matrices.

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