Novel Synthesis of CdSe Quantum Dots in a Confined Space by Using a High Internal Phase Emulsion and Their Application in Fluorescent Labeling

Abstract

AbstractThe synthesis of CdSe quantum dots (QDs) in a confined space constructed by the aqueous continuous phase of high internal phase emulsion (HIPE) at room temperature was proposed, and the obtained high quality QDs was applied as the label of amino groups in epoxy resin. In a typical system of oil‐in‐water HIPE, the aqueous solution film containing selenium powder, cadmium chloride, and 3‐mercaptopropionic acid was squeezed by the droplet of toluene and acted as a nano‐reactor, and then QDs nanoparticles with high fluorescence intensity were generated at room temperature. The morphologies of HIPE containing QDs were observed by fluorescence microscopy, and the QDs product were characterized by high‐resolution transmission electron microscopy and UV‐vis Spectrophotometer. The effect of the confined space, including the stability, the dimension of continuous phase, and the interface structure of HIPE, on the fluorescence performance of QDs were investigated. Furthermore, the mechanism of ‘temporary ligand’ was proposed to explain the better performance of QDs prepared at the introduction of ionic emulsifier. Finally, attributed to the inherent carboxylic end ligands of obtained QDs, it is applied to mark the amino curing agent in the epoxy resin, and the visualized observation of the dispersion of amino curing agent in epoxy matrix was realized.