Abstract:Zirconium oxide nanoparticles with 0.4 wt.% and 0.8 wt.% are incorporated into the Al-0.65Mg-0.05Ga- 0.15Sn (wt.%) alloy anode (base alloy) in order to improve the performance of the resulting anodes. Electrochemical characterization of the reinforced alloys was done by potentiodynamic polarization, electrochemical impedance spectroscopy and galvanostatic discharge and corrosion behavior was evaluated using self-corrosion rate and hydrogen evolution in 4 mol/L KOH solution. The surface morphology of the alloys was also studied using field emission scanning electron microscope (FESEM). The obtained results indicate that the base alloy shows high corrosion rate in 4 mol/L KOH solution by releasing 0.47 mL/(min·cm²) hydrogen gas, whereas the alloy containing 0.8 wt.% ZrO₂ provides the lowest hydrogen evolution rate by releasing 0.32 mL/(min·cm²) hydrogen gas. Furthermore, by increasing zirconium oxide nanoparticles, the corrosion current density of the aluminum anodes is decreased and their corrosion resistance increases significantly compared to the base alloy in alkaline solution. In addition, nanometer-sized zirconium oxide incorporated anodes exhibit the improved galvanic discharge efficiencies, so that 0.8 wt.% nano-zirconium oxide incorporated base alloy displays the highest power density and anodic utilization compared with the others in 4 mol/L KOH solution.

Key words: aluminum anode; zirconium oxide nanoparticles; electrochemical impedance spectroscopy; polarization; corrosion