Cu Atomic Chain Supported on Graphene Nanoribbon for Effective Conversion of CO2 to Ethanol.

Abstract

Cu catalysts are well-known for their good performance in CO2 conversion. Compared to CO and CH4 production, C2 products have higher volumetric energy densities and are more valuable in industrial applications. In this work, we screened the catalytic ability of C2 production on several 1D Cu atomic chain structures and find that Cu edge-decorated zigzag graphene nanoribbons (Cu-ZGNR) are capable of catalyzing CO2 conversion to ethanol, and CH3 CH2 OH is the main C2 product with a maximum free energy change of 0.60 eV. The planar tetracoordinate carbon structures in Cu-ZGNR provide unique chemical bonding features for catalytic reaction on the Cu atoms. Detailed mechanism analyses with transition states search show that CO* dimerization is favored against CHO* formation in the reaction. By adjusting the CO* coverage, the selectivity of the C2 product can be enhanced owing to less pronounced steric effects for COCHO*, which is feasible under experimental conditions. This study expands the catalyst family for C2 products from CO2 based on nano carbon structures with new features.