Insights of Fe 2 O 3 and MoO 3 Electrodes for Electrocatalytic CO 2 Reduction in Aprotic Media.

Transition metal oxides (TMO) have been successfully used as electrocatalytically active materials for CO ₂ reduction in some studies. Because of the lack of understanding of the catalytic behavior of TMOs, electrochemical methods are used to investigate the CO ₂ reduction in thin-film nanostructured electrodes. In this context, nanostructured thin films of Fe ₂ O ₃ and MoO ₃ in an aprotic medium of acetonitrile have been used to study the CO ₂ reduction reaction. In addition, a synergistic effect between CO ₂ and the TMO surface is observed. Faradic cathodic processes not only start at lower potentials than those reported with metal electrodes, but also an increase in capacitive currents is observed, which is directly related to an increase in oxygen vacancies. Finally, the results obtained show CO as a product of the reduction.