Study of the fluorescence of the europium–thenoyltrifluoroacetone–cetyltrimethylammonium bromide–Triton X-100 system

Abstract

The europium–thenoyltrifluoroacetone (TTA)–cetyltrimethylammonium bromide (CTAB)–Triton X-100 system at pH 5.5–7.5 was studied and used for the spectrofluorimetric determination of europium. The excitation and emission wavelengths were 370 and 612 nm, respectively. Fluorescence intensity was a linear function of the concentration of europium in the range 1.0 × 10^–7–1.0 × 10^–9 mol dm^–3. The detection limit was 2.0 × 10^–12 mol dm^–3. The standard additions method was used for the determination of europium in synthetic rare earth oxides and gave satisfactory results. The molar ratio method was carried out spectrofluorimetrically for the determination of the stoichiometric composition of the fluorescent species. A ratio of 1 : 4 : 1 for the ternary Eu–TTA–CTAB complex was found.