Cooperation between the ? and ? phases of bismuth molybdate in the selective oxidation of propene

Abstract
Detailed characterization and catalytic properties of the Bi molybdate system are reported. By using XRD, IR, Raman and XPS techniques, the surface structures of the catalysts are defined, and the observed catalytic synergy is explained in relation to the structure of catalysts. The synergetic effect between α and γ Bi molybdate is attributed to the remote-control mechanism, i.e. an oxygen species emitted by the γ phase can migrate onto the surface of the α phase, where it creates or regenerates the active sites for acrolein formation.