Preparation and Optical Properties of Nano-PhS/SiO2 Aerogel Assemblies
纳米PbS/SiO2气凝胶介孔组装体的制备及光学特性

The studies were focused on the optical properties of supercritical-drying-technique-prepared silica aerogels assembled with PbS colloids synthesized by colloidal chemistry route. Transmission electron microscope was used to image the assembled samples. Fluorescence spectroscopy and absorption spectrophotometer were employed to investigate the optical properties of the assembled systems. Large optical absorption edges red-shift along with the increase of annealing temperature was observed, which can be attributed to the quantum confinement effects. Photoluminescence intensity enhances along with the increase of the annealing temperature to the maximum at 573K, dropping thereafter, and the photoluminescence peaks show small red-shifts in the meanwhile. These phenomena are related to quantum confinement effects, defect states in the particle surface and excitonic recombination probability.