SiO 2 coatings on glass containing copper colloids using the sol-gel technique
- 13 October 1994
- proceedings article
- Published by SPIE-Intl Soc Optical Eng
- p. 120-129
- https://doi.org/10.1117/12.188942
Abstract
A sol-gel method for the preparation of transparent copper nano particle-containing SiO2 coatings on glass has been developed. The sol is synthesized from alkoxysilanes and tetra ethyl orthosilicate with copper ammine complexes, prepared from Cu2+ salts and amino alkoxy silanes. Glass substrates are coated by dipping and layers up to 1 micrometers in thickness are obtained after thermal densification at temperatures between 200 degree(s) - 500 degree(s)C. The Cu colloid formation can be achieved using a reducing atmosphere during densification. Thus reddish-brown colored coatings on glass with optical densities between 0.5 and 2 are obtained. Under ambient air the color turns from reddish-brown to dark green. This process is reversible and by re-heating under reducing conditions the reddish-brown color can be re- established. UV-VIS absorbance measurements and structural investigations by WAXS, TEM, ESCA and SNMS show that the green color is due to an oxide layer at the colloidal interface.Keywords
This publication has 0 references indexed in Scilit: