A study on electrodeposition of Ni-noncovalnetly treated carbon nanotubes nanocomposite coatings with desirable mechanical and anti-corrosion properties

•Successful incorporation of non-covalently functionalized CNTs in electrodeposition bath•Optimum electrodeposition condition obtained for Ni-MWCNT coatings with desirable properties•Remarkable effect of CNTs on the texture, crystallite size, and internal microstrain of the coatings•Nano-indentation and microhardness test confirm increased hardness and elastic modulus of the coatings.•Corrosion rate decreases with increase in CNT content.

In this study, we report on the successful incorporation of non-covalently functionalized multi-wall carbon nanotubes (MWCNTs) in electrodeposition bath using a multi-step dissolution to enhance dispersing and untangling. We observed that a saturation concentration exists for CNT dispersion in the electrodeposition solution and consequently an optimum condition for electrodeposition of Ni-MWCNT was obtained at a current density of 4 A/dm2, and CNT concentration of 2 g/l. X-ray diffraction spectrum revealed a remarkable effect of CNTs on the texture, crystallite size, and internal micro-strain of the coatings. On the basis of nanoindentation and micro-hardness tests, increased hardness and elastic modulus of the coatings were observed which directly depend upon CNT content of the composite coating. Corrosion study results in 3.5% sodium chloride solution showed that corrosion rate decreases with increase in CNT content, though the corrosion rate is directly influenced by nickel crystallite size.