Pt-Decorated Ceria Enhances CO2 Electroreduction in Solid Oxide Electrolysis Cells.

CO2 electroreduction by solid oxide electrolysis cells (SOECs) can not only attenuate the greenhouse effect, but also convert surplus electrical energy into chemical energy. The adsorption and activation of CO2 on the cathode play an important role in the SOEC performance. La0.6 Sr0.4 Co0.2 Fe0.8 O3-δ -Ce0.8 Sm0.2 O2-δ (LSCF-SDC; SDC=samarium-doped ceria) is a promising SOEC cathode. However, its electrocatalytic activity still needs to be improved. In this study, Pt/SDC interfaces are constructed by decorating Pt nanoparticles onto the SDC surface. Electrochemical measurements indicate that the polarization resistance of the SOEC is decreased from 0.308 to 0.120 Ω cm2 , and the current density is improved from 0.913 to 1.420 A cm-2 at 1.6 V and 800 °C. Physicochemical characterizations suggest that construction of the Pt/SDC interfaces increases the oxygen vacancy concentration on the cathode and boosts CO2 adsorption and dissociation, which leads to enhanced CO2 electroreduction performance in SOECs.