Direct cleavage of C=O double bond in CO2 by the subnano MoO x surface on Mo2N

Abstract

Abstract Compared to H2-assisted activation mode, the direct dissociation of CO2 into carbonyl (*CO) with a simplified reaction route is advantageous for CO2-related synthetic processes and catalyst upgrading, while the stable C = O double bond makes it very challenging. Herein, we construct a subnano MoO3 layer on the surface of Mo2N, which provides a dynamically changing surface of MoO3↔MoO x (x < 3) for catalyzing CO2 hydrogenation. Rich oxygen vacancies on the subnano MoO x surface with a high electron donating capacity served as a scissor to directly shear the C = O double bond of CO2 to form CO at a high rate. The O atoms leached in CO2 dissociation are removed timely by H2 to regenerate active oxygen vacancies. Owing to the greatly enhanced dissociative activation of CO2, this MoO x /Mo2N catalyst without any supported active metals shows excellent performance for catalyzing CO2 hydrogenation to CO. The construction of highly disordered defective surface on heterostructures paves a new pathway for molecule activation.