Preparation and characterization of layered molybdenum trioxide pillared with chromia

The well-ordered polyhydroxyacetato-Cr3+ species intercalated molybdenum trioxide by the reaction of an aqueous solution of Cr(OAc)3 with a dispersion of layered sodium molybdenum bronze ([Na(H2O)5]0.25MoO3) was prepared. X-ray fluoroscopy (XRF), TGA and near/UV–VIS spectra showed that the intercalates may mainly be trimers and tetramers. The first chromia-pillared molybdenum trioxide with an interlayer distance of 10.9 Å was then obtained after calcined at 350 °C in a flow of mixed nitrogen and oxygen (4% O2, v/v). The obtained porous material has a surface area of 82.4 m2 g−1, with ca. 60% of pores having rp<20 Å. XPS result suggested that the chromia pillars existed as Cr2O3 in the interlayer of the material.