We studied decomposition pathways of ethanol on Ru(0001) with periodic slab-model calculations using a DFT-GGA approach. We calculated the adsorption modes of ethanol and several of its dehydrogenation products and we evaluated reaction energies as well as activation barriers of pertinent dehydrogenation, C-C, and C-O cleavage steps. The calculated barrier heights of C-C and C-O scission steps can be related to the number of hydrogen atoms bound to the C1-C2 and C1-O moieties of the intermediates, respectively. Two counteracting effects are at work, increasing with each dehydrogenation: (i) higher order of the pertinent bond of the adsorbate, and (ii) stronger substrate-surface interaction and thus better stabilization of the transition state. For most intermediates we determined C-O cleavage to be both kinetically and thermodynamically favored over C-C scission, except for the highly dehydrogenated species CH (k) CO (
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We studied decomposition pathways of ethanol on Ru(0001) with periodic slab-model calculations using a DFT-GGA approach. We calculated the adsorption modes of ethanol and several of its dehydrogenation products and we evaluated reaction energies as well as activation barriers of pertinent dehydrogenation, C-C, and C-O cleavage steps. The calculated barrier heights of C-C and C-O scission steps can be related to the number of hydrogen atoms bound to the C1-C2 and C1-O moieties of the intermediate...
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