A density functional theory study of ethylene hydrogenation on MgO- and γ-Al2O3-supported carbon-containing Ir4
Kezhen Qi1, Jin-Mo Zhao, Gui-Chang Wang
1College of Chemistry and Life Science, Shenyang Normal University, Shenyang, 110034, P. R. China.
Abstract:
Density functional theory was used to investigate the reaction mechanisms of ethylene hydrogenation on MgO(100)- and γ-Al2O3(110)-supported carbon-containing Ir4 clusters. The cluster supported on γ-Al2O3(110) is more active than that on MgO(100), which is consistent with experimental observations. The present calculations show that the binding energies of reactants on the carbon-containing Ir4 cluster are weaker on the γ-Al2O3 supported catalysts compared to the MgO supported Ir cluster. This relatively weak adsorption energy of ethylene on the γ-Al2O3 surface means that ethylene desorption is easier, hence a higher catalytic activity is achieved. To gain further understanding, the energy decomposition method and micro-kinetic analysis are also introduced.
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