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The DFT calculation of CO hydrogenation was studied based on the reaction of co-adsorbed CO and 2H 2 on β-Mo 2 C(1 0 0) and Co Mo carbide slabs. The hydrogenation of CO occurred on the two carbide slabs; undissociative adsorbed CO reacted with three dissociative H's to successively yield CHO, CH 2 O and CH 2 OH adsorbed on the β-Mo 2 C(1 0 0) slab, while the fourth hydrogen attack produced the adsorbed CH 2 and H 2 O. On the other hand, the Co Mo carbide slab produced the adsorbed CH 3 , O and H through CHO and CH 2 O but not through CH 2 OH. CH 3 OH was not produced on both the β-Mo 2 C(1 0 0) and Co Mo carbide slabs, which corresponded to the mass spectroscopic measurement results of no CH 3 OH formation. Furthermore, electronic structure calculations revealed the CO hydrogenation mechanism. A strong peak of the density of states on the Mo contributes to the CO activation, and the addition of Co increases the number of electrons around this peak position, which improves the CO activation. |
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