本文研究了铽一六氟乙酰丙酮一三辛基氧化膦—Triton X—100荧光体系,并确定了最佳的实验条件。用本法可不经萃取直接在水溶液中测定痕量的Tb~(3+),其灵敏度比萃取法增加3—5倍。铽的浓度在5.0×10~(-9)—4.0×10~(-6)M范围内符合比耳定律,检定限可达1.0×10~(-9)M。用标准加入法测定合成稀土氧化物试样中的铽,结果令人满意。本文还初步探讨了表面活性剂对Tb~(3+)荧光反应的增溶、增敏作用的机理。 In this paper, terbium hexafluoroacetylacetone-trioctylphosphine oxide-Triton X-100 fluorescence system was studied, and the best experimental conditions were determined. By this method, the trace amount of Tb 3+ can be directly measured in aqueous solution without extraction, and its sensitivity is 3-5 times higher than the extraction method. The concentration of terbium conforms to Beer’s law in the range of 5.0 × 10 -9 -9.0 × 10 -6 M, and the detection limit can reach 1.0 × 10 -9 M. Terbium in the sample of synthetic rare earth oxide was determined by standard addition method and the results were satisfactory. In this paper, the mechanism of solubilization and sensitization of Tb 3+ fluorescence by surfactant was also discussed.