Oxidative Dehydrogenation of C2H6 and CO2 Mediated by RhxNby -(x + y = 5) Clusters

Abstract

Oxidative dehydrogenation (ODHE) of C2H6 and CO2 to generate C2H4 and CO is of industrially important but remains a long-standing challenge due to the complexity of this co-conversion and the thermodynamically stable and kinetically inert nature of both reactants. Herein, we theoretically demonstrated that the RhxNby– (x + y = 5) bimetallic clusters can drive the ODHE of C2H6 with CO2 to produce C2H4, CO, and H2O. The results identified that the desorption of C2H4 and CO takes place under mild conditions and the increased number of Rh atoms in RhxNby– leads to progressively more difficult C2H4 desorption. In contrast, the formation and evaporation of H2O represent the kinetically and thermodynamically uphill pathway to govern the overall efficiency of ODHE. This finding provides an integrated picture to understand the fundamental mechanisms of ODHE of C2H6 and CO2. The selective release of C2H4 and the rate-determining H2O generation behaviours were rationalized.