The density functional theory using a plane-waves basis set and pseudopotential has been used to study the reaction pathways for ODH of propane on the V₂O₅(001) surface. The calculations indicated that propane adsoprtion step was initiated by the insertion of vanadyl oxygen O (1) into methylene C-H bond forming an iso-propanol structure. This step is the rate-determining step with an activation energy of 23.3 kcal/mol. The subsequent step involved the abstraction of the second hydrogen by O (1) site leading the formation of propene. This process had an activation energy of 22.5 kcal/mol. The elimination of surface bound water molecule at the O (1) was a barrierless process. The energy required for this process was compensated from O₂ dissociative adsorption. Finally, the electronic density of state has been applied to prove the reality of the calculated results. © 2009 Wiley Periodicals, Inc.

Nguyen N.H., Tran T.H., Nguyen M.T., Le M.C.

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Từ khóa : A-plane; Activation barriers; Basis sets; C-H bond; Density of state; Dissociative adsorption; Iso-propanols; Oxidative dehydrogenation of propanes; Oxidative dehydrogenations; Pseudopotentials; Rate determining step; Reaction pathways; Surface-bound water; Vanadyl; Activation energy; Adsorption; Dehydrogenation; Electronic density of states; Oxygen; Propane; Propylene; Vanadium compounds; Density functional theory