Supported vanadium oxide catalysts contain a vanadium oxide phase deposited on a high surface area oxide support (e.g., Al₂O₃, SiO₂, TiO₂, etc.) and have found extensive applications as oxidation catalysts in the chemical, petroleum and environmental industries. This review of supported vanadium oxide catalysts focuses on the fundamental aspects of this novel class of catalytic materials (molecular structures, electronic structures, surface chemistry and structure–reactivity relationships). The molecular and electronic structures of the supported vanadium oxide phases were determined by the application of modern in situ characterization techniques (Raman, IR, UV-vis, XANES, EXAFS, solid state ⁵¹V NMR and isotopic oxygen exchange). The characterization studies revealed that the supported vanadium oxide phase consists of two-dimensional surface vanadia sites dispersed on the oxide supports. Corresponding surface chemistry and reactivity studies demonstrated that the surface vanadia sites are the catalytic active sites for oxidation reactions by supported vanadia catalysts. Combination of characterization and reactivity studies demonstrate that the oxide support controls the redox properties of the surface vanadia sites that can be varied by as much as a factor of ∼10³.

Waste not, want not: Natural gas often escapes or is deliberately burned at remote exploration sites because there is no economical way to transport it to markets. One route proposed for converting its main component, methane, into a more readily transported liquid is conversion to benzene over zeolites containing molybdenum (Mo). However, this method suffers from low conversion efficiency. Gao et al. identified the active Mo nanostructures as well as deactivated carbide species that form during this reaction. They were also able to recover and even enhance the zeolite catalytic activity after oxygen treatments. Science , this issue p. 686