Electrophoretic mobility of silver nanoparticles stabilized with nonionic surfactant Ecosurf SA4: Origin of charged particles, concentration by electrophoresis and production of conductive coatings

Linear electrophoresis in silver organosols was investigated in this work. Silver nanoparticles were obtained in reverse micelles of the nonionic ethoxylated surfactant Ecosurf SA4. Electrokinetic phenom-ena in media with low dielectric permittivity are described for the first time for this class of surfactants. The study of the composition of this surfactant showed weakly bound chlorine. This allowed us to pro-pose a mechanism for the stabilization of charged particles similar to the action of solvating nonpolar sol-vents like chloroform. This mechanism differs from that previously described for the case of both ionic and nonionic surfactants. The dependence of the electrokinetic f-potential of nanoparticles on the con-centration of surfactant is investigated. Electrophoretic concentration with close to quantitative degree of extraction was carried out for the systems with a maximum f-potential value. Silver content in the concentrate is up to 1.9 mol L-1. Thermal treatment allows getting films with a silver content of up to 97% and a conductivity of up to 20 lOhm/h. (c) 2023 Elsevier B.V. All rights reserved.

Automated summary

Linear electrophoresis in silver organosols was studied in this work using reverse micelles of the nonionic surfactant Ecosurf SA4. The electrokinetic phenomena in media with low dielectric permittivity were described for the first time for this type of surfactant. The composition analysis of the surfactant revealed weakly bound chlorine, suggesting a mechanism for the stabilization of charged particles similar to solvation by nonpolar solvents like chloroform. The dependence of the electrophoretic potential of silver nanoparticles on surfactant concentration was investigated, and electrophoretic concentration with high extraction efficiency was achieved.