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An oblique angle electron beam co-deposition technique was used to fabricate nanostructured Sn based thin films: Sn, Cu-Sn and Cu-Sn-C. The morphological and structural properties of the films were observed via scanning electron microscopy (SEM) and thin film X-ray diffraction methods (XRD). The cyclic voltammetry (CV) and the galvanostatic test results demonstrated that the addition of Cu with or without C affected the electrochemical performance of the thin film positively since Cu and C improved both the mechanical and the electrical properties of the nanostructured Sn thin film electrode. The high cycleability and the capacity retention were achieved when the nanostructured Cu-Sn-C thin film was used as an anode material since C increased the mechanical tolerance of the thin film to the volume expansion due to its grain refiner effect, and Cu not only improved the electrical conductivity and the adhesion of the film to substrate but also the mechanical tolerance of the film with its ductile property.

The reversible cyclability of Si based composite anodes is greatly improved by optimizing the atomic ratio of Cu/Si in the films fabricated via magnetron sputtering. The galvanostatic test results show that the thin film anode made of 20%at. Cu delivers 1950 mAhg-1as the initial discharge capacity with 80% Coulombic efficiency. Then, after the 50thcycles 80% of the initial discharge capacity is retained, with 99.5 % Coulombic efficiency. This remarkable performance can be explained by small crystalline sizes, amorphous structures of the thin film and its enhanced physical and mechanical properties due to the 20 %at. Cu content. High specific capacities achieved in this study prove that magnetron sputtering deposition might be a good alternative production technique to fabricate high performance anode materials. Furthermore, this one step, environmentally friendly process enables one to control the film composition, structure as well as adhesion which minimizes delamination and pulverization.

The reversible cyclability of Si based anodes is greatly improved by tuning the atomic ratio of Cu/Si and the thickness of films fabricated via magnetron sputtering. High electrochemical performance is achieved when the thin film made of 10% at.Cu-90% at.Si is used. 1100 mAhg−1specific capacity is delivered after the 100thcycles with 99.7% Coulombic efficiency. This remarkable performance is the result of the amorphous structure and enhanced physical and mechanical properties of the thin film.

This work explores anodic polarization process to generate a surface pattern composed of conical features on an aluminum surface in hot acid mixtures composed of sulfuric and phosphoric acids. It is shown that the composition of the electrolyte with respect to its phosphoric acid and water content and the surface roughness of the aluminum substrate are the critical parameters for the formation of the patterns. The best surface pattern was generated in a hot acidic mixture (60°C) containing 150 mL sulfuric and 350 mL phosphoric acids on a ground aluminum surface. For the formation of conical structures, a mechanism based on the competitive etching action of sulfuric acid and the formation of phosphate precipitates is proposed. Additionally, the possibility of porous anodization of these surfaces in an oxalic acid based electrolyte has been also demonstrated.