Effect of the chemical impurities on the luminescence emission of natural apatites
Por:
Roman-Lopez J., Correcher V., Garcia-Guinea J., Prado-Herrero P., Rivera T., Lozano I.B.
Publicada:
1 ene 2014
Resumen:
This paper reports on both cathodoluminescence (CL) and blue thermoluminescence (TL) emission of well-characterized natural Spanish and Brazilian apatites [Ca5(PO4)3(OH, F, Cl)]. Chemical analyses performed by means of Electron Microprobe Analysis (EMPA) have shown the presence of trace elements that can induce CL bands. In this sense, the apatites shown emission bands peaked at 3.26, 2.86, 2.62, 2.14, 2.02 and 1.94 eV are respectively linked to substitutional Ce3+, Tb 3+, Dy3+, Pr3+, Sm3+ and Mn 2+ in structural Ca2+ positions. The 3.18 eV emission band can be associated with intrinsic electron defects on oxygen of the phosphate group (PO4)3-. The presence of (UO2) 2+ gives rise to an emission at 2.14 eV. All the studied aliquots exhibit one single UV-blue TL peak that modifies the position from one sample to another (370, 256 and 268 C) probably due to (i) the variation in the crystallinity index (from 0.88 to 1.34) and (ii) successive chemical processes such as oxidation, dehydration, dehydroxylation, and fluorine ions losses due to the thermal readout. © 2014 Elsevier B.V. All rights reserved.
Filiaciones:
CICATA-IPN, Legaria 694, 11500 México D.F., Mexico
CIEMAT, Av. Complutense 22, 28040 Madrid, Spain
Museo Nacional de Ciencias Naturales (CSIC), José Gutierrez Abascal 2, Madrid 28006, Spain
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