MPA稳定的CdTe量子点合成及Cu2+检测应用

通过水相法制备3-巯基丙酸(MPA)稳定的碲化镉量子点(CdTe QDs)，即MPA-CdTe QDs。研究Cu²⁺对发射波长为599 nm的MPA-CdTe QDs荧光猝灭效应，发现Cu²⁺浓度与荧光猝灭强度之间满足Stern-Volmer修正方程的线性关系。通过多项式拟合得出Cu²⁺浓度在2.28×10^-6~18.24×10^-6 mol/L和4.8×10^-7~12×10^-7mol/L两个区间范围内与MPA-CdTe QDs的荧光强度F₀/F的多项式关系分别为:F₀/F=7.999-2.470c+0.339c²，F₀/F=3.154-0.160 c+0.049 c²，拟合度分别为0.991，0.993。MPA-CdTe QDs对Cu²⁺检测限可达1.326×10^-7 mol/L。

Synthesis of 3-mercaptopropionic acid-stabilized CdTe quantum dots and its application for the detection of Cu2+

The water-soluble 3-mercaptopropionic acid(MPA)-stabilized CdTe(MPA-CdTe)quantum dots(QDs)were synthesized by aqueous suspension. The study showed that the fluorescence quenching process of Cu²⁺ to MPA-CdTe QDs, whose largest emission peak was 599 nm, could be described well by the theory of fluorescence quenching in competitive absorption systems and its modification of Stern-Volmer equations. By fittings, the results showed a good polynomial relationship between the fluorescence intensity F0/F and the concentration of Cu²⁺, when the concentration was in the range of 2. 28×10^-6-18. 24×10^-6 mol/L and 4. 8×10^-7-12×10^-7mol/L, and two polynomial equations were respectively elucidated based on dynamic and static quenching in competitive-absorption systems: F0/F=7. 999-2. 470c +0. 339 c², F0/F=3. 154-0. 160 c+0. 049 c² and degree of fitting are 0. 991 and 0. 993, respectively. The detection limit was 1. 326×10^-7.