Formation of homogenous copper film on MWCNTs by an efficient electroless deposition process

In this study, copper-coated multi-walled carbon nanotubes (MWCNTs) were prepared using electroless deposition process with an efficient bath composition. As-received MWCNTs underwent acid treatment and subsequent sensitization with tin and activation with palladium before the copper coating process. The electroless deposition process was performed in a bath, which contained copper sulphate pentahydrate as a copper precursor, potassium sodium tartrate as a complexing agent, and formaldehyde as a reducing agent. Surface modifications of MWCNTs were studied by Fourier transform infrared spectroscopy, imaging techniques (scanning electron microscopy, transmission electron microscopy), and X-ray diffraction. On the basis of the results, it was observed that the coating layer covers most surfaces of the nanotubes. Furthermore, copper oxide is also deposited on the surfaces of MWCNTs. The total amount of metals after each sensitization, activation, and metallization step was determined by thermo gravimetric method and induced coupled plasma atomic emission spectroscopy. Coating of MWCNTs was accomplished successfully through adjusting proper chemical ratios and concentrations. The calculated bath efficiency was about 99%