Ceria‐Supported Cobalt Catalyst for Low‐Temperature Methanation at Low Partial Pressures of CO2

The direct catalytic conversion of atmospheric CO2 to valuable chemicals is a promising solution to avert negative consequences of rising CO2 concentration. However, heterogeneous catalysts efficient at low partial pressures of CO2 still need to be developed. Here, we explore Co/CeO2 as a catalyst for the methanation of diluted CO2 streams. This material displays an excellent performance at reaction temperatures as low as 175 °C and CO2 partial pressures as low as 0.4 mbar (the atmospheric CO2 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/CeO2 as compared to a conventional Co/SiO2 catalyst. This work emphasizes the catalytic role of the cobalt‐ceria interface and will aid in developing more efficient CO2 hydrogenation catalysts. Co/CeO2 is an efficient low‐temperature methanation catalyst at CO2 partial pressures down to atmospheric concentrations. Advanced spectroscopic investigations unveiled that the combination of a higher concentration and higher intrinsic activity of active intermediates (formates and carbonyls) explains the high activity, emphasizing the role of the metal‐ceria interface.