Synthesis And Characterization Of CuInS₂ Quantum Dots

As CuInS₂ semiconductor quantum dots?QDs? have a low toxicity, a large optical absorption coefficient and near-infrared light, and are regared to be an ideal luminescent materials for biological imaging, solar cells, light-emitting diodes. This study addressed mainly on the synthesis of CuInS₂ quantum dot by a relatively simple preparation technique, surface modification of CuInS₂/Zn S quantum dots, and their incorporation into silica gel glass. The related results are more important for biological and photovoltaic applications field with fluorescent material of the high efficiency and low toxicity. The main results are summarized as follows:1. Synthesis and characterization of hydrophilic CuInS₂/Zn S Quantum DotsA new method for preparation and surface modification of quantum dots were proposed in an aqueous solution, which has the advantages of a simple operation, a low cost and non-organic solvent. The prepared hydrophilic QDs show the luminous efficiency as high as 25%.2. Synthesis and characterization of hydrophobic CuInS₂/Zn S Quantum DotsUsing solvothermal process, good monodisperse, light stability and fluorescene quantum yield?QY? of 60% were obtained with high pressure sealed container. This method improved the crystallinity to make QDs steady growth. The effects of surfactants on QDs synthesis were also investigated.3. Synthesis and characterization of fluorescent gel glassSilica gel glass incorporating hydrophobic and hydrophilic QDs was prepared 3-Aminopropyltrimethosysilane?APS?. The method is simple and easy to operate, and obtaining the Si O₂-QDs gel glass with a better transparency, heat resistance and high luminescent efficiency. The efficiency is reduced less for embedded hydrophilic QDs in gel glass when comperd that with hydrophobic QDs. However, the efficiencies were greatly affected by temperature. The prepared silica gel glass also has high heat resistance, which will help to develop photovoltaic materials.