基于Mn掺杂ZnS量子点的室温磷光猝灭法测定H_2O_2  

Room-Temperature Phosphorescence Quenching Method for the Detection of H_2O_2 Using Mn Doped ZnS Quantum Dots

作　　者：苏丽霞[1] 董文娟[1] 董川[1] 

机构地区：[1]山西大学环境科学与工程研究中心,山西太原030006

出　　处：《分析科学学报》2013年第3期307-311,共5页Journal of Analytical Science

基　　金：国家自然科学基金(No.21175086);山西省青年科技基金(No.2012021021-4)

摘　　要：以N-乙酰基-L-半胱氨酸为稳定剂,合成了具有独特光学性质的水溶性Mn掺杂ZnS量子点(QDs)。该量子点在室温不除氧的条件下即可发射较强的磷光信号,最大发射波长位于592nm处。在pH=7.0的磷酸盐缓冲溶液中,H2O2对量子点有显著的磷光猝灭作用,且在一定的范围内H2O2的浓度与磷光猝灭值(P0/P)呈现良好的线性关系,以此建立了测定H2O2的新方法。在最佳的实验条件下,该方法的检出限为1.0×10-6 mol/L,线性范围为1.0×10-5～2.5×10-2 mol/L,相关系数为0.9978。通过测定猝灭过程的时间分辨磷光光谱,推断猝灭机理为动态猝灭。Water-soluble Mn2＋ doped ZnS quantum dots （QDs） were synthesized using N-acetyl-L- cysteine as stabilizing agent. A strong room-temperature phosphorescence emission peak of the Mn-doped ZnS QDs was observed at 592 nm without existence of deoxidants and other inducers. In the phosphate buffer of pH 7.0, the room-temperature phosphorescence of the Mn-doped ZnS QDs was quenched by adding H202. Consequently, a new method was proposed for the determination of H202 with the detection limit of 1.0×10 -6 mol/L. And a linear range of 1.0×10 2-2.5× 10-2mol/L was obtained. By measuring the phosphorescence lifetime,we can infer that the quenching behavior of Mn-doped ZnS QDs by H2O2 follows the dynamic mechanism.

关 键 词：Mn掺杂ZnS量子点 室温磷光猝灭 过氧化氢 

分 类 号：O657.39[理学—分析化学]