کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
1482864 | 1510485 | 2011 | 4 صفحه PDF | دانلود رایگان |
![عکس صفحه اول مقاله: Structural and luminescence properties of amorphous SiO2 nanoparticles Structural and luminescence properties of amorphous SiO2 nanoparticles](/preview/png/1482864.png)
We report an experimental study on the photoluminescence band peaked at 2.7 eV (blue band) induced by thermal treatments in nanometric amorphous SiO2. In particular the emission dependence on the nanometric particles size as a function of their mean diameter from 7 nm up to 40 nm is investigated. We found that the emission amplitude increases on decreasing the particle diameter, showing a strong correlation between the blue band and the nanometric nature of the particles. By Raman spectroscopy measurements it is evidenced that the SiO2 nanoparticles matrix is significantly affected by the reduction of size. Basing on the shell-like model, these findings are interpreted assuming that the defects responsible for the photoluminescence are localized on a surface shell of the particles and not simply on their surface. In addition it is found that the generation efficiency of these defects depends on the structural properties of the SiO2 matrix in the surface shell.
Research Highlights
► Amorphous SiO2 nanoparticles with different size.
► Visible luminescence band excited by ultraviolet laser energies.
► Strong dependence on particle size of the luminescence and structural properties.
► Core-shell model of amorphous SiO2 nanoparticles.
► Luminescence centers induced mainly in the surface shell.
Journal: Journal of Non-Crystalline Solids - Volume 357, Issues 8–9, 15 April 2011, Pages 1941–1944