Chemical interaction and diffusion on interface cathode/electrolyte of SOFC

The high-temperature solid oxide fuel cell (SOFC) is suited for the environ mentally acceptable and efficient conversion of chemical into electric ener gy. A prereyui-site for introducing this technology on the market is the co ntrolled formation of the interface between electrodes and the electrolyte. In the case of using an electrolyte based on LaGaO3 the formation of third phases and the diffusion of individual metallic cations from and to the ele ctrolyte was investigated with the aid of point analyses on micrographs of the environment of the interface using quantitative EDS analysis. In case of an anode of Ni-CeO2 cermet the mixed oxide SrLaGa3O7 is formed a nd, in addition, a relatively pronounced transport of La from the electroly te into the CeO2 phase was observed. A relatively strong diffusion of Mn an d an even stronger diffusion of Co into the electrolyte took place between the cathode of, e.g., La0.75Sr0.2Mn0.8Co0.2O3 and the La0.9Sr0.1Ga0.8Mg0.2O 3 electrolyte, whereas a weak transport of Ga to the cathode was identified .