2014 Volume 49 Issue 2 Pages 93-97
We have developed a closed-type environmental-cell (E-cell) transmission electron microscope (TEM) enabling to observe catalyst specimens reacted at ambient conditions. As a part of the developed system, a coaxial-type gas-flow specimen holder has been invented. A hybrid membrane has been also developed as a window material of the E-cell, which consists of an amorphous carbon film and a silicon nitride thin layer. The membrane showed high performances such as less deterioration of spatial resolution, high toughness for pressure difference, and high stability for electron beam irradiation. As an application of our developed system, nanoparticulate gold catalysts supported on TiO2 anatase substrates were observed dynamically at a condition of a selective oxidation of propylene. In-situ observations by the E-cell TEM revealed that product materials of catalytic reaction were formed from the perimeters of the gold/TiO2 interfaces.