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

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 application. 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 nanoribbon (Cu-ZGNR) is capable of catalyzing CO2 to ethanol, and CH3CH2OH 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 C2 product can be enhanced due to less steric effect of COCHO*, which is feasible in experimental condition. This study expands the catalyst family for C2 products from CO2 based on nano carbon structures with new features.