Synergistic impact of multiwalled carbon nanotubes on the properties of Ni-Mo thin-film via electrodeposition technique

Abstract

Carbon nanotubes (CNTs) are the hardest and strongest materials due to their perfect mechanical properties and excellent chemical, electrical, and thermal characteristics. Therefore, CNTs are attractive candidates for the development of innovative multifunctional nanocomposites. The goal of the study was to synthesize and characterize NiMoCNT nanocomposite coatings onto steel substrates by electrodeposition technique to enhance the properties of the NiMo layer coating. The electrodeposition was carried out galvanostatically, and the percentage of MWCNT (wt%) in the composites was investigated under various working circumstances, including current density, pH, temperature, and CNTs concentration in the electroplating bath. Different techniques, such as X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and energy dispersive X-ray analysis (EDS), were used for the composite characterization. Moreover, the corrosion resistance and the nanocomposites’ mechanical characteristics were investigated. The results of the NiMo alloy show that the enhancement in current density decreases the Mo content from 41.8 wt% (at 3.5×10⁻² Acm⁻²) to 31.06 wt% (at 6.5×10⁻² Acm⁻²). On the other hand, the results proved that as the concentration of CNTs in the bath increases, the wt% of CNTs co-deposited in the NiMo matrix enhances, peaking at 22.36 wt% at 0.03 gL⁻¹. Furthermore, the findings show that the Mo content of the coating is reduced when CNTs are present. In comparison to a NiMo coating without CNTs, the composite incorporating CNTs exhibits better corrosion resistance. In addition, the mechanical properties show that the microhardness of NiMoCNT composite-coated steel is better than that of NiMo, and the highest microhardness of NiMoCNT composite coated steel was 4.69 GPa, while pure NiMo coated steel had a microhardness of 2.37 GPa.