Electrochemical Investigation of Thin Nickel, Copper and Silver Films Interfaced with Yttria-Stabilized Zirconia

Abstract

The electrochemical investigation of nickel, copper and silver thin films interfaced with yttria stabilized zirconia (YSZ) solid electrolyte was accomplished to determine their response to polarization in dilute oxygen environments at 350 °C and assess their viability for electrochemical promotion of catalysis (EPOC). Polycrystalline YSZ (8 mol % Y2O3-ZrO2) pellets were synthesized in the lab and films deposited onto them using evaporative physical vapor deposition (PVD). The critical thickness of copper, silver and nickel thin films were foundusing in-situ resistance measurements. Following this, 50 and 100 nm copper and nickel films were studied using solid electrolyte cyclic voltammetry (SECV) to determine their response to polarization. Given that silver thin films at such thicknesses are thermally unstable, a film of 800 nm was used in this study. The materials were found to respond to polarization in different ways, forming oxides according to Wagner and Mott-Cabrera oxidation models.