Ceria‐Supported Cobalt Catalyst for Low‐Temperature Methanation at Low Partial Pressures of CO(2)

The direct catalytic conversion of atmospheric CO(2) to valuable chemicals is a promising solution to avert negative consequences of rising CO(2) concentration. However, heterogeneous catalysts efficient at low partial pressures of CO(2) still need to be developed. Here, we explore Co/CeO(2) as a catalyst for the methanation of diluted CO(2) streams. This material displays an excellent performance at reaction temperatures as low as 175 °C and CO(2) partial pressures as low as 0.4 mbar (the atmospheric CO(2) concentration). To gain mechanistic understanding of this unusual activity, we employed in situ X‐ray photoelectron spectroscopy and operando infrared spectroscopy. The higher surface concentration and reactivity of formates and carbonyls—key reaction intermediates—explain the superior activity of Co/CeO(2) as compared to a conventional Co/SiO(2) catalyst. This work emphasizes the catalytic role of the cobalt‐ceria interface and will aid in developing more efficient CO(2) hydrogenation catalysts.