Co-electrodeposition of inorganic fullerene (IF-WS 2) nano-particles with cobalt from a gluconate bath with anionic and cationic surfactants

Abstract

The codeposition of IF-WS 2 particles (130 nm diameter) in a cobalt matrix has been investigated. The influence of cobalt content and anionic and cationic surfactants on composite coatings produced using direct current (DC) and pulse reverse plating (PRP) are described. The coatings were assessed by XRD, SEM and EDX. The cationic surfactant promoted particle encapsulation and high oxygen content in DC coatings, whilst anionic surfactants do not offer controlled particle codeposition. Improved particle content and distributions were obtained by PRP, on the high cobalt bath containing anionic surfactant. The particle content was optimised by fixing the anodic cycle time t a, and varying the cathodic cycle time, t c. Sound coatings with a high percentage (11 vol.%) of particles were produced at t c of 60 s. This was encouraged by electrophoretic attraction of particles in the anodic phase and then encapsulation during the cathodic phase of the cycle.