Nanocrystalline tin oxides and nickel oxide film anodes for Li-ion batteries

Tin oxides and nickel oxide thin film anodes have been fabricated for the first time by vacuum thermal evaporation of metallic tin or nickel, and subsequent thermal oxidation in air or oxygen ambient. X-ray diffraction (XRD) and scanning electron microscopy (SEM) measurements showed that the prepared films are of nanocrystalline structure with the average particle size <100 nm. The electrochemical properties of these film electrodes were examined by galvanostatic cycling measurements and cyclic voltammetry. The composition and electrochemical properties of SnOx (1 < x < 2) films strongly depend on the oxidation temperature. The reversible capacities of SnO and SnO2 films electrodes reached 825 and 760 mAh g(-1), respectively, at the current density 1 of 10 muA cm(-2) between 0.10 and 1.30 V. The SnOx film fabricated at an oxidation temperature of 600 degreesC exhibited better electrochemical performance than SnO or SnO2 film electrode. Nanocrystalline NiO thin film prepared at a temperature of 600 degreesC can deliver a reversible capacity of 680 mAh g(-1) at 10 muA cm(-2) in the voltage range 0.01-3.0 V and good cyclability up to 100 cycles. (C) 2002 Elsevier Science B.V. All rights reserved.