The Facile Dissociation of Carbon-Oxygen bonds in CO2 and CO on the Surface of LaCoSiHx Intermetallic Compound.

In catalysis science, the electronic structure of the active site determines the structure-activity relationship of the catalyst to a large extent. Therefore, modulating the electronic structure has become a main route for the rational design of metal-based catalyst materials. In this work, we prepared a LaCoSiH x material that has more electronegativity and a lower workfunction than traditional supported Co-based catalysts. Using CO 2 methanation as a model catalytic reaction, the facile dissociation of CO 2 and CO (a key reaction intermediate) on the surface of the LaCoSiH x catalyst is observed by various experimental methods (e.g., in situ Raman and FTIR) at room temperature. Moreover, theoretical calculation results further show that LaCoSiH x has a much stronger capacity for carbon-oxygen bond activation than does the Co surface. The intrinsic mechanism is attributed to the marked electron transferring from catalysts into the antibonding orbital of CO 2 and CO.