Unraveling the mechanism of CH3CH2OH dehydrogenation on m-ZrO2(111) surface, Au13 cluster, and Au13 cluster/m-ZrO2(111) surface: A DFT and microkinetic modeling study

Abstract

The dehydrogenation of CH3CH2OH to produce CH3CHO and H2 is crucial for generating valuable chemicals. This study uses density functional theory (DFT) and microkinetic modeling to elucidate the reaction pathways on the m-ZrO2 (111) surface, Au13 cluster, and Au13 cluster/m-ZrO2(111) surface. Dehydrogenation on both the m-ZrO2(111) surface and Au13 cluster occurs via two key steps. The first step involves the cleavage of the OH bond in CH3CH2OH, forming a CH3CH2O moiety and an OH bond with the lattice oxygen on m-ZrO2 (111) surface or with a low-coordination Au atom in the Au13 cluster, respectively; while the formation of H2 takes place in the second step; however, the results microkinetic modeling render low values for the corresponding rate constants for this reaction path. Although the Au13cluster/m-ZrO2(111) surface introduces an additional step, where the H atom migrates from the m-ZrO2 (111) surface to the Au13 cluster, we shown that the relative energy of the three transition states is similar, the activation barriers are lower, and the rate constants are favorable for the dehydrogenation of CH3CH2OH. These results demonstrate the potential of the Au13 cluster supported on m-ZrO2(111) for efficient and selective CH3CHO and H2 production, providing valuable insights for advanced catalytic system design.