Interaction of solid electrolyte La0.88Sr0.12Ga0.82Mg0.18O2.85 with hydrogen, water vapor, and carbon dioxide

Abstract

The air,Au/La 0.88 Sr 0.12 Ga 0.82 Mg 0.18 O 2.85 /Au,air cells are studied by an impedancemetry method before and after a week-long exposure at 700 ° C to atmospheres of hydrogen, humid air, and carbon dioxide. Blank specimens of the same electrolyte are examined by methods of x-ray diffraction, Raman scattering (RS), and x-ray photoelectron spectroscopy. The fact that the shape of the RS spectra and the shape of the electrode impedance dispersion alter unequivocally suggests that, at the very least, the electrode surface interacts with all the gases. The interaction in question is reversible in the case of hydrogen and carbon dioxide. In the case of water vapor, the interaction is irreversible.