Na<sub>2</sub>O Promotion on CO<sub>2</sub> Hydrogenation on the χ-Fe<sub>5</sub>C<sub>2</sub>(2 0 0) Surface

Understanding the origin of the high activity of Na 2 O promotion on the χ-Fe 5 C 2 (2 0 0) surface during CO 2 hydrogenation is imperative. In this work, we revealed how Na 2 O promoted the catalytic performance of χ-Fe 5 C 2 during CO 2 hydrogenation. Detailed analyses confirmed that Na 2 O addition facilitated the adsorption of CO 2 and promoted the desorption of product (C 2 H 4 ). Electronic structure calculations suggested that the electron donating ability of Na could enhance the dissociation of CO 2 , which is essential for producing hydrocarbons from CO 2 .