Distinguishing the CO_2 Electro-Catalytic Reduction Pathway on Modified Ni/GDC Electrodes for the SOEC H_2O/CO_2 Co-Electrolysis Process

摘要

Modified X-Ni/GDC electrodes (where X = Au, Mo and Fe) have been studied, in the form of half-electrolyte supported cells, for their performance in the RWGS through catalytic-kinetic measurements. The samples were tested at open circuit potential conditions in order to elucidate their catalytic activity towards the production of CO (r_(co)). The first results revealed that Fe and Mo modification enhances the catalytic production of CO, in the whole studied temperature range (800-900°C), reaching the thermo-dynamic equilibrium. Recent results from the electrocatalytic investigation on full electrolyte-supported cells are also presented. The derived catalytic profile of the electrodes, is used as a reference towards the distinction of the electro-catalytic pathway for the CO_2 reduction. Specifically, it is examined whether co-electrolysis is mainly catalytically/thermodynamically driven or it is a combination of electro- and catalytic processes.