TRLFS characterization of Eu(III)-doped synthetic organo-hectorite.
Europium(III) was coprecipitated with the clay mineral hectorite, a magnesian smectite, following a multi-step synthesis procedure. Different Eu(III) species associated with the proceeding synthetic hectorite were characterized by selectively exciting the 5D0-->7F0 transition at low temperature (T < 20 K). Fluorescence decay times indicated that Eu(III) ions may be incorporated in the octahedral layer of the brucite precursor as well as in the octahedral sheet of the clay mineral. The excitation spectra indicated that the substitution of the divalent Mg by the trivalent Eu induced local structural deformation. This investigation implements the molecular-level understanding of the f element structural incorporation into the octahedral layer of sheet silicates by coprecipitation with clay minerals from salt solutions at 100 degrees C.
Finck
Nicolas
N
Institut für Nukleare Entsorgung (INE), Forschungszentrum Karlsruhe, PO Box 3640, D-76021 Karlsruhe, Germany. Nicolas.finck@ine.fzk.de
Stumpf
Thorsten
T
Walther
Clemens
C
Bosbach
Dirk
D
D005063:Europium / Q000737:chemistry*; D011850:Radioactive Waste / Q000032:analysis; D017640:Silicates / Q000737:chemistry*
D011850:Radioactive Waste; D017640:Silicates; C013547:hectorite; D005063:Europium; C033214:Smectite