Effect of nano zirconia on electrochemical performance, corrosion behavior and microstructure of Al-Mg-Sn-Ga anode for aluminum batteries

Abstract

In this research, stir cast Al-0.65Mg-0.15Sn-0.05Ga-xZrO2 (wt.%) reinforced alloys containing micro-additives of ZrO2 nanoparticles are fabricated to be used as an anode in aluminum batteries. The mean size of the ZrO2 particles was 40 nm and the amount of addition varies from 0.05 to 0.8 wt.%. Electrochemical characterization of the reinforced alloys was investigated by potentiodynamic polarization and electrochemical impedance spectroscopy and corrosion behavior were evaluated using self-corrosion rate, hydrogen evolution, and anode efficiency measurements in 3 wt.% NaCl solution. The microstructure of the reinforced alloys was also studied using field emission scanning electron microscope (FESEM) and undissolved particles were analyzed by energy dispersive spectrometer (EDS). Since a portion of the ZrO2 nano-particles enters the grain boundaries during solidification of the alloy, the improper dissolution of the anode is reduced by suppression of non-coulombic loss in these points. Hence, the hydrogen evolution and corrosion current density of the reinforced alloys decreased and the anode efficiency increased by the addition of ZrO2 nano-particles to the Al-0.65Mg-0.15Sn-0.05Ga (wt.%) alloy which in case of using reinforced anodes in an aluminum battery, energy dissipation would be reduced. In general, the addition of ZrO2 nanoparticles resulted in a reduced non-coulombic loss, which occurs due to self-corrosion and enhances the efficiency of the reinforced anodic alloys, especially in higher current densities. The severity of these changes is augmeted by increasing the amount of ZrO2 nano-particles in the reinforced alloys.