Novel M1/M2 Heterostructure in Mo-V-M-Ta (M = Te or Sb) Complex Oxide Catalyst Revealed by Aberration Corrected HAADF STEM

In-situ X-ray diffraction study of phase crystallization from an amorphous MoVTeNb oxide catalyst precursor

The formation of the crystalline phases M2, M1, orthorhombic MoO3, and a tetragonal M5O14 (M=Mo,V,Nb) type phase during heat treatment of an amorphous Mo-V-Te-Nb oxide precursor in helium is investigated applying in-situ X-ray diffraction. The precursor was synthesized by precipitation, spray-drying and subsequent calcination of the dried orange powder in air at 275°C. Crystallization of M2 sta...

Double aberration-corrected TEM/STEM of tungstated zirconia nanocatalysts for the synthesis of paracetamol

We report highly active tungstated zirconia nanocatalysts for the synthesis of paracetamol by Beckmann rearrangement of 4-hydroxyacetophenone oxime. Double aberration-corrected (2AC)-TEM/STEM studies were performed in a JEOL 2200FS FEG TEM/STEM at the 1 Angstrom (1 Å = 0.1 nanometer) level. Observations at close to zero defocus were carried out using the AC-TEM as well as AC-STEM including high...

Nanostructural and chemical characterization of supported metal oxide catalysts by aberration corrected analytical electron microscopy

1359-0286/$ see front matter 2011 Elsevier Ltd. A doi:10.1016/j.cossms.2011.06.001 ⇑ Corresponding authors. Addresses: Departmen Vanderbilt University, Nashville, TN 37235, USA Materials Science and Engineering, Lehigh Univer USA(C.J. Kiely). E-mail addresses: [email protected] (W (C.J. Kiely). The performance of catalyst materials are usually governed by the precise atomic structure and c...

Correlative Aberration-Corrected STEM-HAADF and STEM-EELS Analysis of Interface-Induced Polarization in LaCrO3-SrTiO3 Superlattices

Observation of Pt-atom complexes in CaTi1-xPtxO3-δ

The ‘intelligent catalyst’ concept, involving cyclical movement of precious metal atoms in and out of a perovskite oxide lattice, was proposed by Nishihata et al. in 2002, and the precious metal atom (Pd) was then believed to occupy the B site in the perovskite (LaFeO3) lattice, based on X-ray anomalous diffraction measurements [1]. Since then, B site occupancy has generally been assumed for al...