Theoretical study of partial oxidation of ethylene by vanadium trioxide cluster cation

Density functional theory (DFT) study of reaction between vanadium trioxide cluster cation (VO₃⁺) and ethylene (C₂H₄) to yield VO₂⁺ + CH₃CHO (acetaldehyde) and VO₂CH₂⁺ + HCHO (formaldehyde) is carried out. Structures of all reactants, products, intermediates, and transition state in the reaction have been optimized and characterized. The results show unexpected barriers in the reaction due to the existence of a η²-O₂ moiety in the ground state structure of VO₃⁺. The initial reaction steps combining ethylene adsorption, C=C activation and O-O cleavage are proposed as rate limiting processes. Comparison of reactions of VO₃⁺ + C₂H₄ with VO₃ + C₂H₄ and VO₂⁺ + C₂H₄ in the previous studies is made in detail. The results of this work may shed light on the understanding of C=C bond cleavage in related heterogeneous catalysis. Supported by the Hundred Talents Fund, Chinese Academy of Sciences and National Natural Science Foundation of China (Grant No. 20703048)