The effect of SiO2 nanoparticles dispersion on physico-chemical properties of modified Ni–W nanocomposite coatings

• Published in: Applied surface science 2015-01, Vol.324, p.369-379
• Main Authors: Sassi, W., Dhouibi, L., Berçot, P., Rezrazi, M.
• Format: Article
• Language: English
• Subjects: Coatings; Dispersions; Electrical conductivity; Media; Nanoparticles; Nanostructure; Nickel; Ni–W alloy; Silicon dioxide; SiO2 nanoparticles; X-ray photoelectron spectroscopy; Zêta potential
• ISSN: 0169-4332; 1873-5584
• DOI: 10.1016/j.apsusc.2014.10.142

•SiO2 nanoparticles are agglomerated at pH 3 but well dispersed at pH 4.•Nano-SiO2 has been not only adsorbed onto the Ni–W layer but also through it.•Ni–W/SiO2 nanocomposite electroplated at pH 3 presents glass palate like-structure.•The pH 4 enhances the crystallization of the Ni–W/SiO2 nanocomposite coating.•The nano-SiO2 improves the mechanical and electrical proprieties of Cu. In this work, we study the effect of pH on morphology, composition and crystallographic orientation during pulse electroplating of Ni–W/SiO2 nanocomposite coating from citrate-ammonia media. SEM and AFM analysis shows that the nanocomposite coatings obtained with well dispersed SiO2 nanoparticles were smoother, more compact and with finer grain size. Furthermore, XPS, GDOES and XRD reveal a good crystalline structure with the detection of new intermetallic phases. The interface electrochemical behavior and stability of the studied coatings into 3% NaCl media were discussed in the consideration of electrical conductivity and microhardness.