Alkali ion intercalation inV2O5:: preparation and laboratory characterization of thin films produced by ALD

Thin films Of V2O5 act as performant alkali ion storage material, with applications mostly in Li microbatteries or in electrochromic windows. Oxide films less than 100 nm thick have been obtained by the Atomic Layer Deposition (ALD) method. The alkali ion insertion has been performed either via an electrochemical cathodic reaction in a non-aqueous solvent, or from the vapour phase in a vacuum chamber at RT. Both experimental procedures promoted the insertion of large amounts of the alkali ion with consequent reduction of the oxidation state of V, from 5+ to 4+ and even to 3+, measured with XPS-UPS. The reversibility of this reaction was a function of the amount of ionic charge inserted, of the substrate used (FTO, Cr-coated glass) and of the heat treatment adopted for the ALD film. Copyright (C) 2006 John Wiley & Sons, Ltd.