Demonstration of direct conversion of CO2/H2O into syngas in a symmetrical proton-conducting solid oxide electrolyzer

We have previously reported the electrochemical reduction of CO2 to CO with simultaneous steam electrolysis in a proton conducting solid oxide electrolyzer (PCSOE); however, the conventional Ni-cermet electrode is rapidly oxidized by H2O/CO2 in cathode that causes cell performance degradation. In this work, we report a novel symmetrical PCSOE with redox-stable LSCM ((La0.75Sr0.25)(0.95)Cr0.5Mn0.5O3-delta) electrode for the electrochemical conversion of CO2/H2O into syngas (CO/H-2). The Ru catalyst is impregnated to LSCM to improve electrode activity. Electrochemical measurements demonstrate that the CO2 is electro-chemically reduced to syngas (CO/H-2) with simultaneous steam electrolysis. The loading of Ru catalyst promotes the electrochemical process with higher Faradic efficiency while induces a more competitive process of hydrogen evolution at 700 degrees C. Copyright (C) 2015, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.