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In the past nearly two decades, the synthesis and analysis of semiconductor nanomaterials applied research has been widespread concern. More research is quantum dots. The quantum dots have excellent optical properties, compared with the conventional organic dye, quantum dots having a wide excitation spectrum, the emission spectrum is adjustable, narrow emission peak, Stokes shift and difficult photolysis. This article is divided into a total of three chapters. Chapter Summary, mainly on the basic properties of the quantum dots, photoluminescence characteristics, surface modification of quantum dots as fluorescent probes applied research progress are outlined. Chapter II, Chapter III study, the use of water-phase synthesis method stabilizer thioglycolic acid water-soluble CdTe quantum dots and fluorescence properties of quantum dots made basic research based on the mechanism of action of electrostatic quantum dots with cationic surfactant CTAB interaction mechanism; quantum dots to the quantum dot fluorescent probes, fluorescence quenching degree and Hg correlation between 2 ion concentration determination of the aqueous solution Hg 2 . The research report specified by the following two parts: 1. The fluorescence properties of CdTe quantum dots prepared with CTAB Interaction of thioglycolic acid stability (TGA) set of water-soluble CdTe quantum dots, and study the interaction between the quantum dots with CTAB. By UV - visible absorption spectroscopy, fluorescence emission spectra, and transmission electron microscopy were characterized by the synthesis of quantum dots, the effects of the reaction time of the quantum dot particle size and quantum yield as well as the stability of the quantum dot. The results showed that the synthesis of quantum dots with excellent luminescent properties, particle size distribution, good stability, control the reflux time quantum dot synthesis of the desired size. The synthesis of CdTe quantum dots, with CTAB role, CTAB caused by the presence of the quantum dot fluorescence quenching and the CTAB concentration of 1.0 × 10 -6 mol / L to 1.0 × 10 -4 mol / L range, quantum dot fluorescence quenching rate at first increases and then decreases trends; accompanied by changes in the fluorescence intensity of quantum dot fluorescence emission peak appeared the first redshift After blue shift phenomenon. Based on the experimental results, the preliminary study of the above quantum dots with CTAB electrostatic mechanism. 2. Surface modification of CdTe quantum dot fluorescent probe for the determination of trace mercury in water consistency became TGA modified water-soluble CdTe quantum dots. Quantum dot synthesis characterization using transmission electron microscopy, fluorescence spectroscopy, UV - visible spectrum. It was found that Hg 2 strong quenching effect of CdTe quantum dot fluorescence were determined based on this quenching effect of the aqueous solution of trace Hg 2 . Buffer system, pH value, the concentration of the quantum dots, mixing time, and other factors were investigated Determination of Hg 2 system analysis features of quantum dots. Selected experimental conditions the Hg 2 concentration of 8.0 × -9 to 1.5 × 10 -7 mol / a linear relationship between the logarithm of L, and the relative fluorescence intensity (logI 0 / I) with a detection limit of 2 × 10 -9 mol / L, RSD is 3.5% (C = 3.0 × 10 -8 mol / L, n = 11).
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