Syngas production through CH4-assisted co-electrolysis of H2O and CO2 in La0.8Sr0.2Cr0.5Fe0.5O3-δZr0.84Y0.16O2-δ electrode-supported solid oxide electrolysis cells

High temperature co-electrolysis of H2O/CO2 allows for clean production of syngas using renewable energy, and the novel fuel-assisted electrolysis can effectively reduce consumption of electricity. Here, we report on symmetric cells YSZ-LSCrF vertical bar YSZ vertical bar YSZ-LSCrF, impregnated with Ni-SDC catalysts, for CH4-assisted co-electrolysis of H2O/CO2. The required voltages to achieve an electrolysis current density of -400 mA.cm(-2) at 850 degrees C are 1.0 V for the conventional co-electrolysis and 0.3 V for the CH4-assisted co-electrolysis, indicative of a 70% reduction in the electricity consumption. For an inlet of H2O/CO2 (50/50 vol), syngas with a H-2:CO ratio of approximate to 2 can be always produced from the cathode under different current densities. In contrast, the anode effluent strongly depends upon the electrolysis current density and the operating temperature, with syngas favorably produced under moderate current densities at higher temperatures. It is demonstrated that syngas with a H-2:CO ratio of approximate to 2 can be produced from the anode at a formation rate of 6.5.mL min(-1).cm(-2) when operated at 850 degrees C with an electrolysis current density of -450 mA.cm(-2). (C) 2021 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.