Ni/CGO-Based Electrolyte-Supported Cells During Co-Electrolysis: The Role of Feed Gas Impurities

Abstract

In the present study, durability aspects of state-of-the-art Ni/CGO-based electrolyte-supported cells are investigated in steam electrolysis, dry CO2 electrolysis, and co-electrolysis operation under various operating conditions by means of current-voltage characteristics and electrochemical impedance spectroscopy, and high performance was demonstrated. Electrochemical steam reduction kinetics were shown to be faster than carbon dioxide reduction. Performance in co-electrolysis was observed to be close to performance in steam electrolysis. Furthermore, strong degradation of the Ni/CGO fuel electrode surface process was observed in CO/CO2 atmosphere under the absence of current which suggests the presence of impurities in the feed gas that poison the electrode surface.