无机材料学报

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纳米PbS/SiO2气凝胶介孔组装体的制备及光学特性

姚连增; 叶长辉; 牟季美; 蔡维理   

  1. 中国科学技术大学材料科学与工程系, 合肥 230026
  • 收稿日期:2000-01-14 修回日期:2000-03-01 出版日期:2001-01-20 网络出版日期:2001-01-20

Preparation and Optical Properties of Nano-PhS/SiO2 Aerogel Assemblies

YAO Lian-Zeng; YE Chang-Hui; MOU Ji-Mei; CAI Wei-Li   

  1. Department of Materials Science and Engineering; University of Science and Technology of China; Hefei 230026; China
  • Received:2000-01-14 Revised:2000-03-01 Published:2001-01-20 Online:2001-01-20

摘要: 对用自行研制的SCD-I型高压釜制备的SiO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.

关键词: 介孔组装体, 气凝胶, 量子限域效应

Abstract: 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.

Key words: meso-porous assemblies, aerogels, quantum confinement effect

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