关键词: 溶胶凝胶法, 量子点玻璃, 表面活性剂的吸附, 吸收边界蓝移, 纳米粒子

Abstract: The sol-gel process has been applied to preparation of small size PbS crystal doped silica glasses. Silica glasses containing 0.87%-6.6% PbS were synthesized in a process which includes the two-step hydrolysis of Si(OC₂H₅)₄ and Pb(CH₃COO) ₂·3H₂O, drying and heating of doped gels, and the reaction by exposing the porous glass of PbO/SiO₂ to H₂S gas. The sol-gel transition point and specific surface area for the doped system were measured. Surfactant microemusion is added to the Sol-gel process to obtain smaller size PbS microcrystal with narrower size distribution. From the results of transmission electron micrographs, PbS crystals were 3-6nm in diameter for methanol method and 2-3nm for microemulsion method. In the optical absorption spectra, the absorption edge exhibited a blue shift compared with that of the bulk PbS, especially for the samples made by microemusion method. Thus the quantum size effect was found for glasses containing PbS prepared by the sol-gel process.

Key words: sol-gel process, quantum dot glass, surfactant adsorption, absorption edge blue shift, nanocomposite