Codeposition of Particles: Role of Adsorption of the Electroactive Species

Abstract

Cu-Al 2 O 3 composite coatings were obtained from a 0.2 M Cu 2+ and 0.6 M monosodium glutamate electrolyte whose pH was adjusted at different values in the 3-10 range. Particle charging behavior was studied through ζ-potential measurements and the potential of zero charge of the electrode was determined using Electrochemical Impedance Spectroscopy. Scanning Electron Microscopy was used to characterize coatings surface and to detect particle incorporation. The wt% of alumina in the deposits was estimated using Energy Dispersive Spectroscopy performed on their cross section. Under these experimental conditions high incorporation of particles into the copper matrix was observed, which was ascribed to the increased Cu 2+ adsorption on Al 2 O 3 surface induced by the presence of glutamate in the electrolyte. It was found that hydration forces strongly influence the codeposition of particles as proposed by Fransaer et al. The results were used to identify the relevant steps in the process and to develop a semi-empirical model.

Direct Current Electrodeposition of Zn-SiC Nanocomposite Coatings from Citrate Bath

“…5a). Such maxima of ceramic particles incorporation in electrodeposited metal matrices have been observed in the literature, [60][61][62] suggesting that they occur at the potential of zero charge (E pzc ). 60,61,63 The latter is defined as the potential at which the net surface charge density equals zero.…”

Effect of thermal processing on the tribology of nanocrystalline Ni/TiO2 coatings

“…Optimization of the coating parameters can lead to substantial improvements of the coating's wear resistance [20,21]. The inclusion of nanoparticles in the coating has been shown to significantly improve hardness and other mechanical properties of the coatings [22]. The major challenge, however, is obtaining a uniform distribution of the ceramic particles in the coating.…”

Ultrasound Assisted Electrodeposition of Cu-SiO2 Composite Coatings: Effect of Particle Surface Chemistry

“…Thus, Cu 2+ adsorption is hampered under these conditions, which leads to lower incorporation rates. 55,62 When functionalized particles were added to the solution, a higher content of SiO 2 in the deposit was obtained for most experimental conditions, which suggests that the presence of amino groups at the particle surface enhances Cu 2+ uptake. Nevertheless, for these particles US irradiation had a negative effect on the codeposition of Cu and SiO 2 both in the absence and presence of P-7.…”

“…The influence of j on the amount of SiO 2 registered is in agreement with previously reported results 29,42,82 and has been explained in detail somewhere else. 56,62 Briefly, as current density increases, the electrode potential (E) shifts away from the potential of zero charge (E PZC ) (Table II) favoring the interaction between the electrode and water molecules. This results in a strongly attached hydration layer which hinders particles from reaching the electrode surface, leading to lower incorporation rates.…”