Characterization of ceramic hydrogen separation membranes with varying nickel concentrations

Ceramic hydrogen separation membranes in the stoichiometric form BaCe0.8Y0. 2O3, doped with various concentrations of nickel, were characterized by uti lizing X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), and atomic-force microscopy ( AFM). Characterization was performed at room temperature, 550 degrees C and 650 degrees C, and after exposure to hydrogen. Migration of nickel to the surface and changes in both elemental composition and oxidation states were observed at elevated temperatures. The concentration of nickel significant ly affects surface morphology and roughness. (C) 2000 Published by Elsevier Science B.V.