In-situ Observation of Nano-particulate Gold Catalysts under Reaction Gas and Non-reaction Gas Conditions
نویسنده
چکیده
Gold exhibits catalytic activity when it is in the form of fine particles having a size of less than 10 nm and is tightly supported on specific metal oxides such as TiO2, etc [1]. To reveal its mechanism, dynamic observation of the sample structures during the reaction by the transmission electron microscope (TEM) is quite essential. “Environmental-cell (E-cell) TEM” technique [2], which enables gas introduction around specimens, is one of the most powerful methods for the purpose. The authors also have developed the closed-type E-cell TEM [3], and had revealed that the shape of catalytic gold nano-particles are changing during reaction [4]. In the paper, we report about difference of the shape change of gold nano-particles between under reaction gas and non-reaction gas conditions.
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