Improvement of windowed type environmental-cell transmission electron microscope for in situ observation of gas-solid interactions.
We have developed an improved, windowed type environmental-cell (E-cell) transmission electron microscope (TEM) for in situ observation of gas-solid interactions, such as catalytic reactions at atmospheric pressure. Our E-cell TEM includes a compact E-cell specimen holder with mechanical stability, resulting in smoother introduction of the desired gases compared with previous E-cell TEMs. In addition, the gas control unit was simplified by omitting the pressure control function of the TEM pre-evacuation chamber. This simplification was due to the successful development of remarkably tough thin carbon films as the window material. These films, with a thickness of <10 nm, were found to withstand pressure differences >2 atm. Appropriate arrangement of the specimen position inside the E-cell provided quantitatively analyzable TEM images, with no disturbances caused by the windowed films. As an application, we used this E-cell TEM to observe the dynamic shape change in a catalytic gold nanoparticle supported on TiO(2) during the oxidation of CO gas.
Kawasaki
Tadahiro
T
Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa, Nagoya 464-8603, Japan. kawasaki@nuee.nagoya-u.ac.jp
Ueda
Kouta
K
Ichihashi
Mikio
M
Tanji
Takayoshi
T