New Insights into Catalytic Sites from Slow-Electron Velocity Map Imaging of Cryogenically Cooled Transition Metal Oxide Anion Clusters

Abstract

Spectroscopy and dynamics of bare and complexed transition metal oxide clusters has been investigated using slow electron velocity-map imaging of cryogenically cooled anions (cryo-SEVI). This research program is motivated by the importance of transition metal oxide catalysts in many key chemical reactions. Understanding the reactive sites in catalysts is of prime importance in chemistry, and transition metal oxide clusters represent tractable model systems for these catalysts. Cryo-SEVI is a high resolution (sub-meV) variant of anion photoelectron spectroscopy that provides a unique probe of size-selected transition metal oxide clusters and their complexes with reactants, reactive intermediates, and products. It has been shown to yield highly vibrationally resolved spectra even for clusters comprising multiple transition metal atoms. Comparison of these spectra with Franck-Condon simulations enables one to distinguish among possible isomeric structure and to make definitive structural assignments. First targets for this effort were the suboxide clusters Fe n O, V n O, and Co n O. We've also targeted the product formed by reaction of TiO 2 with water. SEVI experiments on both bare metal oxide clusters and reactive intermediates have been complemented by infrared spectroscopy.

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Document Details

Document Type
Technical Report
Publication Date
Mar 15, 2019
Accession Number
AD1085907

Entities

People

  • Daniel Neumark

Organizations

  • University of California Regents

Tags

Communities of Interest

  • Air Platforms
  • C4I
  • Energy and Power Technologies

DTIC Thesaurus Topics

  • Catalysts
  • Chemical Reactions
  • Chemical Synthesis
  • Chemistry
  • Dynamics
  • Electrons
  • Frequency
  • High Resolution
  • Infrared Spectroscopy
  • Ionization
  • Metal Oxides
  • Oxides
  • Spectra
  • Spectroscopy
  • Titanium
  • Titanium Oxides
  • Transition Metals

Fields of Study

  • Chemistry

Readers

  • Electrochemical Engineering/ Fuel Cell Technologies
  • Molecular Photonics/Laser Physics
  • Quantum Chemistry

Technology Areas

  • Microelectronics