This work mainly investigated the influences of some factors, such as, synthesis methods, precursor alternatives, and vacuum heat-treating process, etc, on the fluorescent characteristics of the semiconductor quantum dots synthesized by aqueous phase. The research results indicate that the fluorescent characteristic of water-solution sample prepared from Na2SO3 precursor was sensitive to water bath heating time, and specially, its photoluminescence spectrum shows the unique phenomenon of double excitation and emission peaks. Meanwhile, the fluorescent characteristic of water-solution sample prepared from NaBH4 precursor is slightly influenced by water bath heating time, and the surface of CdSe quantum dots could be passivated by the excessive amount of NaBH4 precursor, which results in the effective decrease of surface traps and great enhancement of quantum yield. Furthermore, the fluorescent emission peaks of samples could be sharpened by vacuum heat-treating process, with its spectral full width at half of maximum (FWHM) around 30-40 nm, so the emission peaks become redshift, of which the intensity greatly increases.
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机译:selective separation of some ecotoxic transition metal ions from aqueous solutions using immobilized macrocyclic material containing solid phase extraction system