Galvanostatically electrodeposited coatings of pure Sb or co-deposited Sb and Sb 2 O 3 nanoparticles, prepared from antimony tartrate solutions, were studied as anode materials in Li-ion batteries. It is demonstrated that the co-deposition of 20-25% (w/w) Sb 2 O 3 results from a local pH increase at the cathode (due to protonation of liberated tartrate) in poorly buffered solutions. This causes precipitation of Sb 2 O 3 nanoparticles and inclusion of some of the particles in the deposit where they become coated with a protecting layer of Sb. Chronopotentiometric cycling of the deposits, which also were characterized using, e.g., SEM, TEM, and XRD, clearly showed that the Sb 2 O 3 -containing deposits were superior as anode materials. While the Sb/Sb 2 O 3 coatings exhibited a specific capacity close to the Sb theoretical value of 660 mA‚h‚g -1 during more than 50 cycles, the capacity for the Sb coatings gradually decreased to about 250 mA‚h‚g -1 . This indicates that the influence of the significant volume changes present upon the formation and oxidation of Li 3 Sb was much smaller for the Sb/Sb 2 O 3 nanoparticle coatings. The improved performance can be explained by significant formation of Sb 2 O 3 during the reoxidation, the presence of smaller Sb particles in the Sb/Sb 2 O 3 coatings, and the formation of buffering nanoparticles of Li 2 O in a matrix of Sb during the first reduction cycle for the Sb/Sb 2 O 3 deposits.

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Nanolayers of Cu and Cu 2 O with a wide range of layer thicknesses have been produced using pulsed galvanostatic and potentiostatic electrodeposition from alkaline Cu͑II͒-citrate solutions. The thicknesses of the individual Cu and Cu 2 O layers can be independently controlled and the composition of the multilayered materials, which also were studied using electrochemical quartz crystal microbalance, X-ray diffraction, and scanning electron microscopy, can be varied from pure Cu to pure Cu 2 O by varying the current density or the deposition potential. It is shown that some of the deposited Cu 2 O is reduced during the subsequent copper deposition step and that the influence of this effect depends on the Cu͑II͒ concentration, the Cu 2 O microstructure, and the deposition mode. Additional Cu 2 O deposition is demonstrated to take place after the copper deposition step due to comproportionation and precipitation of Cu 2 O. This effect facilitates electrodeposition of Cu 2 O on Cu. Deposition of Cu on the Cu 2 O layer formed by comproportionation and precipitation was likewise found to be more straightforward than on electrodeposited Cu 2 O. Well-defined nanolayered Cu/Cu 2 O materials are generally best manufactured using pulsed galvanostatic techniques because a much larger fraction of the Cu 2 O was found to be reduced during the subsequent Cu deposition pulse in pulsed potentiostatic depositions.

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