Enhanced luminescence of the europium(III)-terbium(III)-dibenzoylmethane-ammonia-acetone system and its application to the determination of europium

Abstract

The enhanced luminescence of the Eu-dibenzoylmethane(DBM)-NH₃ system in the presence of Tb³⁺ and the effect of solvents on that system in the absence of Tb³⁺ were studied. The optimum conditions for co-luminescence of the Eu-Tb-DBM-NH₃ system were examined. The optimised procedure was applied to the determination of trace amounts of Eu. The detection limit is 4.0 × 10^–11M, which is about two orders of magnitude lower than that of the system in the absence of Tb. An intermolecular transfer of energy from the enhancing complex to the fluorescing complex is proposed.