Insight into the Preference Mechanism of CHx (x = 1–3) and C–C Chain Formation Involved in C2 Oxygenate Formation from Syngas on the Cu(110) Surface

Abstract

The possible formation pathways of CHx (x = 1–3) and C–C chain involved in C2 oxygenate formation from syngas on an open Cu(110) surface have been systematically investigated to identify the preference mechanism of CHx (x = 1–3) and C–C chain formation. Here, we present the main results obtained from periodic density functional calculations. Our results show that all CHx (x = 1–3) species formation starts with CHO hydrogenation; among them, CHx (x = 2, 3) are the most favored monomers, however, CH3OH is the main product from syngas on the Cu(110) surface, and the formation of CHx (x = 1–3) cannot compete with CH3OH formation. Further, on the basis of the favored monomer CHx (x = 2, 3), we probe into the C–C chain formation of C2 oxygenates by CO or CHO insertion into CHx (x = 2, 3), as well as the hydrogenation, dissociation, and coupling of CHx (x = 2, 3), suggesting that CO insertion into CH2 to form C2 oxygenates is the dominant reaction for CH2 on the Cu(110) surface with an activation barrier of 44.5...