Comparison of nanotube formation on zirconium in fluoride/glycerol electrolytes at different anodizing potentials

Porous anodic films on zirconium, formed potentiostatically in fluoride/glycerol electrolytes of different water content, are examined by ion beam analysis and analytical electron microscopy for the purpose of understanding the generation of nanotubes. Cross-sections of the films, prepared by focused ion beam, showed the presence of oxide-based nanotubes within a fluoride-based matrix. The atomic ratio of fluorine to oxygen in the films decreases with the addition of water to the electrolyte and with increase of the potential. The compositions and morphologies of the films, and their dependence on the anodizing conditions, are discussed in relation to the growth mechanism of the films.

Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slideHighlights► Nanotube formation is investigated on zirconium anodized in fluoride/glycerol electrolytes. ► TEM/FIB reveal film morphologies dependent on water content of the electrolyte and potential. ► IBA/TEM show increased fluorine in films formed at lower potential and lower water contents in the electrolyte. ► Growth mechanisms of the films are considered.