Electrochemical Promotion of CO2 Hydrogenation Using a Pt/YSZ Fuel Cell Type Reactor

The hydrogenation of CO2 is a reaction of key technological and environmental importance, as it contributes to the sustainable production of fuels while assisting in the reduction of a major greenhouse gas. The reaction has received substantial attention over the years within the catalysis and electrocatalysis communities. In this respect, the electrochemical promotion of catalysis (EPOC) has been applied successfully to the CO2 hydrogenation reaction to improve the catalytic activity and selectivity of conductive films supported on solid electrolytes. However, designing an effective electrocatalytic reactor remains a challenge due to the connections required between the electrodes and the external potentiostat/galvanostat. This drawback could be alleviated if the catalytic reaction occurs in a reactor that simultaneously operates as a power generator. In this work, the Electrochemical Promotion of the CO2 hydrogenation reaction in a low-temperature solid oxide electrolyte fuel cell (SOFC) reactor is studied using yttria-stabilized zirconia (YSZ) and a platinum (Pt) electrode catalyst. The system has been studied in two distinct operation modes: (i) when the necessary energy for the electrochemical promotion is produced through the parallel reaction of H-2 oxidation (galvanic operation) and (ii) when a galvanostat/potentiostat is used to impose the necessary potential (electrolytic operation). The performance of the fuel cell declines less than 15% in the presence of the reactant mixture (CO2 and H-2) while producing enough current to conduct EPOC experiments. During the electrolytic operation of the electrochemical cell, the CO production rate is significantly increased by up to 50%.

Automated summary

The hydrogenation of CO2 is crucial for sustainable fuel production and greenhouse gas reduction. Electrochemical promotion of catalysis (EPOC) has shown potential in improving catalytic activity and selectivity in this reaction. Designing an effective electrocatalytic reactor remains a challenge, but the use of a low-temperature solid oxide electrolyte fuel cell (SOFC) reactor has been studied for promoting CO2 hydrogenation.