Use of an 'Open' Triple-Phase Boundary to Demonstrate Where Chromium Contaminants Initially Deposit at the LSM-YSZ Interface.

摘要

Background & Method:A number of research groups have demonstrated that pure and mixed metal chromium oxides preferentially deposit around the general vicinity of the triple-phase boundary (TPB) during cathodic polarization of porous strontium-doped lanthanum manganite (LSM) cathodes in yttria-doped zirconia (YSZ)-based solid oxide fuel cells.This deposition directly leads to increased polarization losses by blocking diffusion of oxygen to the active sites (1-4).It is also well understood that the chromium originated from the chromium oxides found on the surface of the metal alloys used as the electrical contact to the cathode.Likewise,there are many factors that influence the rate of chromium species deposition at the cathode-electrolyte interface region.