中文摘要：

以三聚磷酸钠（STPP）为稳定剂，硫脲为硫源，在碱性介质中成功合成分散较均匀、水溶性好、半峰宽为25nm左右的CdS量子点（QDs）．研究三聚磷酸钠和硫脲的用量、反应时间及pH值等条件对CdSQDs发射光谱特性的影响．以该纳米粒子作为离子探针，建立测定痕量Fe2＋的荧光猝灭方法．结果表明：在0．02～1．20μmol·L-1范围内，Fe2＋对STPP-CdSQDs荧光猝灭符合Stern-Volmer方程，483nrn处R／F与Fe2＋呈现良好的线性关系，检测限为6．7nmol·L^-1；对于实际矿泉水样中Fe的测定，其相对标准偏差为2．2％～3．8％。回收率为95．0％～105．0％．

英文摘要：

The uniform dispersion and water-soluble CdS quantum dots （QDs） stabilized by sodium tripolyphosphate （STPP） were successfully synthesized in an alkaline medium, where the S2 was obtained from thiourea. The half peak width of CdS QDs was about 25 nm. The fluorescence spectral properties of CdS QDs with varying adding amount of STPP and thiourea, pH values, and reaction time were investigated. By the STPP-CdS QDs as ion probe, a new fluores cenee quenching method for the determination of trace iron （ II ） was developed. The fluorescence quenching results followed the Stern-Volmer equation, and the values of F0/F at 483 nm is linearly proportional to the concentration of Fe2＋ from 0. 02-1.20 μmol - L-1. The detection limit of the developed method was 6. 7 nmol · L-1 for Fe2＋. Mineral water samples were analyzed with the relative standard deviation （RSD） of 2. 2~3.8% and the recovery of 95. 0%105. 0%.