Authors: Tomoki Akita Shingo Tanaka Koji Tanaka Masatake Haruta Masanori Kohyama
Publish Date: 2011/02/15
Volume: 46, Issue: 12, Pages: 4384-4391
Abstract
Sequential highangle annular darkfield scanning transmission electron microscopy HAADFSTEM was used to clarify the detailed process of structural changes in Au/CeO2 catalysts found in our previous TEM observations The layerbylayer shrinkage of a Au nanoparticle on CeO2 during electron beam irradiation and recovery at the same position after switching off the beam were observed with clear resolution of Ce and Au atomic columns Displaced Au atomic columns at the perimeter of the Au/CeO2 interface during the electron beam irradiation have been analyzed using firstprinciples calculations which indicate that such Au atoms at the perimeter edge are located above oxygen vacancies or Ceterminated surface regions The present behavior of Au atoms and nanoparticles provides valuable insights into the mechanisms of both structural changes and catalytic activity of Au/CeO2 catalystsThis study was supported by the Japan Society for the Promotion of Science JSPSGrantinAid for Scientific Research B 18360322 and GrantinAid for Specially Promoted Research 19001005 The authors are grateful to Ms J Maekawa for her assistance with sample preparation
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