Electrochemical Behavior of Ni-CZO Cermet Anodes Prepared By Glycine Nitrate Process

Abstract

The impact of H2O for H-2 oxidation on Ni-Ce0.75Zr0.25O2 (Ni-CZO) anode material synthesized by glycine-nitrate-process has been investigated under dry and wet H-2 fuel atmospheres over a range of operating conditions using yttria-stabilized zirconia (YSZ) electrolyte. Using electrochemical impedance spectroscopy (EIS), the polarization resistance (comprised of high frequency (HF) and low frequency (LF) features) of Ni-CZO symmetrical cells (Ni-CZO/YSZ/Ni-CZO) has been studied. The LF arc was almost negligible at all the operating temperatures in wet condition, and the HF arc linearly increased with time at 800 degrees C only in dry condition. The EIS response in dry and wet H-2 conditions clearly exhibited that water vapor enhanced the dissociative adsorption and surface diffusion of hydrogen and achieved stable electrochemical performance at 3PB on the Ni-CZO cermet.