Interaction of vanadium oxide cluster anions with water: an experimental and theoretical study on reactivity and mechanism

Abstract

Vanadium oxide cluster anions (V_xO_y⁻, x = 2–3; y = 3–7) are produced by laser ablation and reacted with water in a fast flow reactor. A time-of-flight mass spectrometer is used to detect the cluster distribution before and after the reactions. Reaction channels of molecular hydrogen elimination (for V_2,3O₃⁻), water association (for V₂O₅⁻ and V₃O_6,7⁻) and the coexistence of both channels (for V₂O₄⁻ and V₃O_4,5⁻) are observed. V₂O₆⁻ and V₃O₈⁻ are nearly inert toward water. Density functional theory (DFT) calculations are performed to study the reaction mechanism of V₂O₃⁻ in different spin states with water and the results support the experimental observation. The reaction mechanism of V₂O₃⁺ with water is also studied, which is in agreement with the experimental report in previous literature [Eur. J. Inorg. Chem., 2008, 4961] that molecular hydrogen elimination is a minor reaction channel for V₂O₃⁺ + H₂O. The influence of cluster charge states and oxidation states of vanadium atoms on the cluster reactivity are presented based on the experimental and theoretical studies.