High-energy Electron Beam Stimulated Chemical Reaction 0603993

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High-energy Electron Beam Stimulated Chemical
Reaction 0603993

• An external electric field induced chemical
  reactions, known as electrochemical reactions, as
  in rechargeable batteries, are redox reactions,
  involving oxidation and reduction process. The
  dynamics of high-energy electron beam stimulated
  reactions, however, are quite different. The
  interactions of incident high-energy electrons
  with atoms and atom electrons are more
  complicated, involving direct transfer of kinetic
  energy and radiolysis. Very little is known about
  the process of reaction at atomic scale. In order
  to observe the dynamical process of electron beam
  stimulated reactions, we have developed
  techniques utilizing time-resolved electron
  energy-loss spectroscopy (EELS) in a transmission
  electron microscope. So far successes of this
  program include the direct observation of the
  high-energy electron beam stimulated transition
  from Al(OH)3 to ?-type amorphous Al2O3 (see
  figure). First, the H atoms are removed quickly
  by knock-on interaction, leaving O in surplus
  (Al(OH)3 ? AlO3 3H?). The O2 then quickly forms
  and the layered Al(OH)3 structure collapses (AlO3
  ? ?-Al2O3 O2?). The newly formed structure
  contains tetrahedrally coordinated Al, as in
  ?-Al2O3. This knowledge also aids the proper
  characterization of H-containing materials.

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High-energy Electron Beam Stimulated Chemical
Reaction 0603993
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High-energy Electron Beam Stimulated Chemical
Reaction 0603993

• Broad impacts
• This program uniquely combines the electron
  energy-loss spectroscopy and electron irradiation
  techniques. It offers the realistic prospect of
  understanding and manipulating atomic structures
  by new means in order to obtain wanted novel
  properties.