Electronic and chemical properties of mixed-metal oxides: adsorption of SO2 on SrTiO3(001)

Properties of nanoscale materials are very interesting and these are either comparable to or superior to those of bulk. These materials are interesting due to their exciting size dependent optical, electronic, magnetic, thermal, mechanical and chemical properties. Different mole ratios of nanostructured mixed metal oxides of LaCo x Fe 1-x O 3-δ (x = 0 to 1) were prepared by the sol–gel method by varying the mole ratios of iron and cobalt substrates. The compounds were sintered for 700°C in the tubular furnace for 8 h. The purity of the compounds was analyzed by TG-DTA. The compounds were characterized by X-ray diffraction (XRD), Fourier transform infrared (FT-IR) and scanning electron microscopy (SEM) studies were employed to study the structural phases, vibrational frequencies, surface morphology of the highest humidity sensing compounds.

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Studies on the Behavior of Mixed-Metal Oxides: Structural, Electronic, and Chemical Properties of β-FeMoO4

The Journal of Physical Chemistry B ◽

10.1021/jp001652c ◽

2000 ◽

Vol 104 (34) ◽

pp. 8145-8152 ◽

Cited By ~ 26

Author(s):

José A. Rodriguez ◽

Jonathan C. Hanson ◽

Sanjay Chaturvedi ◽

Amitesh Maiti ◽

Joaquín L. Brito

Keyword(s):

Metal Oxides ◽

Chemical Properties ◽

Mixed Metal Oxides ◽

Mixed Metal ◽

And Chemical Properties

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Electronic and chemical properties of mixed-metal oxides: Adsorption and reaction of NO on SrTiO3(100)

The Journal of Chemical Physics ◽

10.1063/1.1539864 ◽

2003 ◽

Vol 118 (14) ◽

pp. 6562-6571 ◽

Cited By ~ 28

Author(s):

J. A. Rodriguez ◽

S. Azad ◽

L.-Q. Wang ◽

J. Garcı́a ◽

A. Etxeberria ◽

...

Keyword(s):

Metal Oxides ◽

Chemical Properties ◽

Mixed Metal Oxides ◽

Mixed Metal ◽

And Chemical Properties

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Characterization of Mixed-Metal Oxides Using Synchrotron-Based Time-Resolved x-ray Diffraction and x-ray Absorption Spectroscopy

MRS Proceedings ◽

10.1557/proc-590-113 ◽

1999 ◽

Vol 590 ◽

Author(s):

José A. Rodriguez ◽

Jonathan C. Hanson ◽

Joaquín L. Brito ◽

Amitesh Maiti

Keyword(s):

Metal Oxides ◽

Density Functional ◽

Chemical Properties ◽

Local Symmetry ◽

Mixed Metal Oxides ◽

X Ray Diffraction ◽

Time Resolved ◽

X Ray ◽

Mixed Metal ◽

X Ray Absorption

ABSTRACTExperiments are described showing the utility of synchrotron-based time-resolved x-ray diffraction (TR-XRD) and x-ray absorption near-edge spectroscopy (XANES) for characterizing the physical and chemical properties of mixed-metal oxides that contain Mo and a second transition metal (Fe, Co or Ni). TR-XRD was used to study the transformations that occur during the heating of a FeMoO4/Fe2(MoO4)3 mixture and the α⇒β phase transitions in CoMoO4 and NiMoO4. The Mo LII- and O K-edges in XANES are very useful for probing the local symmetry of Mo atoms in mixed-metal oxides. The results of XANES and density-functional calculations (DMo13, DFT-GGA) show large changes in the splitting of the empty Mo 4d levels when going from tetrahedral to octahedral coordinations. XANES is very useful for studying the reaction of H2, H2S and SO2 with the mixed-metal oxides. Measurements at the S K-edge allow a clear identification of S, SO2, SO3 or SO4 on the oxide surfaces. Changes in the oxidation state of molybdenum produce substantial shifts in the position of the Mo LII- and MIII-edges.

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