Electroless plating of Co-Fe on the surface of MWCNTs

Multiwalled carbon nanotubes (MWCNTs) were electroless plated with cobalt-iron (Co-Fe). Palladium-atom centers were formed on the surface of MWCNTs by a pretreatment before the plating. Three main parameters, the molar ratio of C_Co²⁺:C_Fe²⁺, the concentration of complexing agent, and the temperature of plating bath, were changed to investigate their effects, whereas the concentrations of metal salts and reducing agent and pH were kept unchanged. A layer of metal deposited neatly with a Co-Fe content above 90% was obtained when the molar ratio of C_Co²⁺:C_Fe²⁺ was 9:1, the concentration of complexing agent was 0.32 mol/L, and the temperature of plating bath was 60°C. Metal granules were obtained, or the content of Co-Fe was much less in the other conditions investigated.