Synthesis of nanostructured zirconia by anodization at low potentials

This work reports the synthesis of nanostructured ZrO2 by anodization of zirconium electrodes at potentials well below the range of 10–50 V used as a standard procedure. Zirconium was first anodized in a 1M (NH4)2SO4 electrolyte and then further anodized in the presence of fluoride ions added to the electrolyte as NH4F. The maximum potential applied to zirconium during the whole process was 1 V with respect to an Ag/AgCl (sat.) reference electrode. Amorphous films of ZrO2 consisting of nanopores and nanowire-like structures were produced with this low-potential methodology.