Ni/nano-TiO2 composite electrodeposits: Textural and structural modifications

Passivation Behavior and Surface Resistance of Electrodeposited Nickel-Carbon Composites

“…25 Addition of composite particles to the electroplating solution at a low current density and a low pH value changes the preferred orientation of Ni grain growth to (100) grains (represented by (200) reflection). 26 As seen on the XRD results where the preferred orientation of pure Ni is (111), then it changes to (200) of which peak intensity grows with increasing carbon content. Zhang et al found that (100) grains have the lowest stress and the lowest strain energy density in a plane of film surface so that the change in preferred orientation from (111) to (100) may be due to the minimization of the strain energy in consideration of the fact that increasing carbon content gives an increase in internal strain of the plating layer.…”

Electrodeposition of Metal Matrix Nanocomposites: Improvement of the Chemical Characterization Techniques

“…Considering the electrodeposition of Ni-SiC, Gyftou et al have concluded, from the study of the textural perfection of the deposits, that the presence of nanoparticles led to the worsening of the quality of the [1 0 0] preferred orientation, observing a mixed crystal orientation through [1 0 0] and [2 1 1] axes when high concentration of embedded particles were used (Gyftou et al, 2008). Some authors (Spanou et al, 2009) assume that the modification of metallic orientation in addition to the decrease of crystallite size point to an effective incorporation or embedding of the particles. In accordance with this, the embedding SiC nano-particles in a Ni metallic matrix resulted in the deposition of composite with smaller crystallite sizes and more structural defects than those of pure Ni deposits (Gyftou et al, 2008;Angerer et al, 2009).…”

“…For the Ni-TiO 2 system, the experimental data revealed that co-deposition of TiO 2 nanoparticles is favoured at low pH values and current densities, implying that there is a plentiful adsorption of H + on the titania surface. As the particle surfaces become positively charged they will be strongly adsorbed on the cathode leading to an enhanced electrolytic co-deposition (Spanou et al, 2009). Nevertheless, in some published works, it is pointed out the electrodeposition of negatively charged particles into Ni matrix with success.…”

Preparation and Characterization of Ni–TiO2 Nanocomposite Coatings Produced by Electrodeposition Technique

“…Ni matrix composites reinforced by TiO2 nanoparticles can be successfully synthesized by electrodeposition utilizing either sulfamate or Watts plating baths (Spanou et al, 2009). During this process, the powder particles are suspended in a conventional electrolyte and are captured in the growing metal coating (Abdel Aal and Hassan, 2009).…”