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对用自行研制的ＳＣＤ－Ｉ型高压釜制备的ＳｉＯ２气凝胶与用胶体化学方法制备的ＰｂＳ纳米粒子的组装体系的光学性质进行了研究．用透射电镜观察了其形貌，用光吸收谱仪及荧光光谱仪测定其光吸收谱及荧光谱．发现样品的光吸收边随退火温度升高由可见逐渐移到红外波段．样品的光致发光强度随退火温度上升先增强直至５７３Ｋ，而后随退火温度上升而减弱．我们认为光吸收边红移是由量子限域效应引起的，而荧光强度变化与ＰｂＳ表面缺陷及激子的复合几率变化有关．
The optical properties of silica aerogels prepared by self-developed SCD-I autoclave and PbS nanoparticles prepared by colloidal chemistry were investigated. The morphology was observed by transmission electron microscopy. The optical absorption spectra and fluorescence spectra were measured by optical absorption spectrometer and fluorescence spectrometer. It is found that the light absorption edge of the sample gradually moves to the infrared band as the annealing temperature increases. The photoluminescence intensity of the sample increases with annealing temperature up to 573K, and then decreases with the increase of annealing temperature. We believe that the light absorption edge redshift is caused by the quantum confinement effect, and the change of fluorescence intensity is related to the variation of PbS surface defects and the recombination probability of excitons.