ZINC COLLOIDS AND FILMS FROM NON-AQUEOUS SOLVENTS .7.

Citation
G. Cardenas et al., ZINC COLLOIDS AND FILMS FROM NON-AQUEOUS SOLVENTS .7., Boletin de la Sociedad Chilena de Quimica, 40(3), 1995, pp. 261-268
Citations number
19
Categorie Soggetti
Chemistry
ISSN journal
03661644
Volume
40
Issue
3
Year of publication
1995
Pages
261 - 268
Database
ISI
SICI code
0366-1644(1995)40:3<261:ZCAFFN>2.0.ZU;2-5
Abstract
Zinc colloids and zinc metal films have been prepared by Chemical Liqu id Deposition (CLD) from non-aqueous solvents. The goal is the synthes is of new colloids from another approach in order to obtain zinc collo ids and from them reactive solids for organic reductions. The zinc is evaporated to yield atoms which are solvated at low temperature (77 de grees K) and during the warm up colloidal sets are obtained. The chara cterization of these colloids was achieved by several studies such as stability, electrophoresis, flocculation speed, and transmission elect ron microscopy. organic solvents such as acetone, 2-butanone, isobutyl methyl ketone, tetrahydrofurane, N,N-dimethylformamide, dimethylsulfo xide, ethanol, 2-propanol, benzene and toluene, were used. These studi es are showing that zinc colloids are very reactive in the presence of oxygen. Their particles are spherical and negatively charged. Upon so lvent removal these colloidal particles grow to form metallic films, w hich contain some residual solvent. Characterization of these films by FTIR, thermogravimetry (TG) and electron microscopy have been carried out. These studies are showing that the solvents are incorporated int o the films. TG studies reveal that the loss of fragments occurs after 300 degrees C. Scanning electron microscopy gives us their surface mo rphology. The films are showing a metal composition ranging from 65.0 to 80% w/w and the carbon content is very low (around 1% w/w). The fil ms are extremely reactive in the presence of oxygen.