Influence of plating time and concentration on the thickness of the Ni coating on carbon nanotubes

To improve the compatibility of carbon nanotubes(CNTs) and the metal matrix by reducing the surface activation energy, the CNTs with Ni coatings were obtained by an electroless deposition process. The effects of the plating time and the concentration of plating solution on the thickness of the Ni coatings were studied. The results show that as the plating time is prolonged, the depositional particles become larger and the thickness of coatings increases. Moreover, the numbers of depositional particles increase and the coatings gradually become densified with the increase of concentration of the plating solution. The CNTs coated with a dense Ni layer can be successfully prepared with the plating solution concentration of 0.08 mol/L Ni²⁺ and the plating time of 30 min in this experiment, and the Ni layer possesses well interfacial interaction with CNTs and has a thickness of 10 nm. Heat treatment can effectively relive the stress between Ni layer and CNTs and increase interfacial interaction.