Preparation of Conductive Silver Films from Electrophoretic Concentrates Stabilized with Sorbitan Monooleate and Sodium Bis(2-Ethylhexyl)Sulfosuccinate in n-Decane

Abstract

A high-productivity method has been proposed for the synthesis of silver nanoparticles with sizes of 11.2 ± 0.3 nm in water-in-oil emulsions stabilized with sorbitan monooleate (Span 80). It has been shown that, in the course of the synthesis, initial reagents are transferred from emulsion droplets into Span 80 micelles. As a result, nanoparticles are formed due to the intermicellar exchange by the mechanism of micellar (microemulsion) synthesis. The addition of an anionic surfactant, sodium bis(2-ethylhexyl)sulfosuccinate (AOT) provides the nanoparticle surface with a negative charge (ζ-potential is –50.0 mV). This has made it possible to employ nonaqueous electrophoresis for obtaining a liquid concentrate, the evaporation of which has yielded a dry Ag/Span 80/AOT composite. Silver contents in the concentrate and composite are 30 and 70%, respectively. X-ray diffraction and thermal analysis methods have been used to study the composite thermolysis, which results in the formation of conductive silver films (0.43 Ω/sq).