Highly fluorescent CdTe@SiO₂ particles prepared via reverse microemulsion method

Following on from our previous investigations, fluorescent core/shell CdTe@SiO₂ particles were prepared via the water-in-oil (W/O) reverse microemulsion method. It was found out that incubating the as-prepared aqueous CdTe quantum dots stabilized by thioglycolic acid in ammoniacal solution not only increased the fluorescence quantum yield of CdTe quantum dots but also gave rise to high retention of fluorescence throughout the silica coating. Under optimized conditions, the fluorescence quantum yield of CdTe quantum dots encapsulated in silica particles reached 47%. Both absorption and fluorescence spectroscopy were used in combination with X-ray photoeleetron spectroscopy and electrophoresis to investigate the fluorescence enhancement effect occurring during incubation, the high retention of fluorescence quantum yield, as well as the formation of multicore/shell CdTe@SiO₂ particles as a result of the incubation process imposed on the as-prepared CdTe quantum dots.