Synthesis, Characterization, and Electrochemical Properties of Nanocrystalline Silver Thin Films Obtained by Spray Pyrolysis

Abstract

Silver thin films were prepared using a spray pyrolysis method, silver acetate as the precursor, and stainless steel, heated at 225 and 300°C, as the substrate. Structural and morphological analyses carried out using X-ray diffraction, X-ray photoelectron spectroscopy (XPS), and scanning electron microscopy methods revealed the formation of highly homogeneous, porous coatings ca. 1 μm thick and with nanometric Ag particles as the main component. The presence of small amounts of Ag2OAg2O was also inferred from XPS data. The reduction process of these films, which are used as electrodes over the potential range 3.0-0.0 V in lithium cells, consisted of several steps involving the formation of a solid electrolyte interface between 1.5 and 0.2 V, and at least two Ag-Li alloys below 0.2 V, the patterns of which were indexed in the cubic and tetragonal systems, respectively. The alloying/dealloying processes are reversible, and the cell can deliver a capacity of 600 Ah kg−1600 Ah kg−1 in the potential window 1.0-0.0 V. © 2003 The Electrochemical Society. All rights reserved.