**Author details**

**5. Conclusions**

%, at scan rate 0.1667 mV/s [54].

212 Nanocomposites - Recent Evolutions

of nanoparticles, including Mt, SiC and Al2

in the system. When nano-Al2

Al2 O3

ZnNi nanocomposites can be formed by incorporating nanoparticles into the coating during an electrochemical deposition. The nanoparticles under study do not appear to affect the electrochemical behavior or electrochemical deposition mechanism of zinc-nickel γ-phase alloy formation. Anomalous deposition of the zinc-nickel alloy was observed which is consistent with formation of the γ-phase alloy, but small anodic shifts were observed in the ALSV scans of the metal species in the ZnNi-Mt bath as compared to baths without Mt nanoparticles present.

**Figure 10.** Potentiodynamic polarization curves of ZnNi and ZnNi-Mt nanocomposite coatings, electrolyte NaCl, 3.5 wt

also noted no overall effect on the electrochemical behavior of the system. The addition

also affected the onset of hydrogen evolution,

O3

particles were dispersed uniformly throughout the coating,

O3

appearing more cathodically, leads to alloy formation with less entrapped hydrogen.

O3

pushing the onset to more cathodic potentials, which can be an advantage in an aqueous plating system as it broadens the working window for the deposition. Zinc-nickel γ-phase deposition requires a high overpotential to overcome the kinetic limitations of nickel deposition, this added benefit of shifting the reduction of the metals anodically with the onset of hydrogen

Particle dispersion in the electrolytic bath is an important factor when considering deposition. Optimal corrosion protection is acquired from systems with better dispersion of nanoparticles

and incorporated in the matrix, they were able to protect the coating from corrosive medium, increasing the corrosion potential and retarding corrosion onset. Agglomerated nano-Al2

Heidi Conrad1 \* and Teresa D. Golden2

