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Detailed Structural Analysis of Pd Particles through Use of XAFS and STEM-EELS in Tandem

Article of Honda R&D Technical Review Vol.29 No.1


In order to realize more effective use of palladium, one of the precious metals employed in catalysts for the conversion of automobile exhaust gases, it is important to possess an understanding of the detailed structure of the metal particles. However, it has not proved easy to visualize the structure of palladium particles in three dimensions using individual analytic techniques. A detailed analytic technique was therefore created through the use of X-ray absorption fine structure analysis, scanning transmission electron microscopy and electron energy loss spectroscopy, and first principle calculations in tandem. The application of this analytic method made it possible to formulate a model of palladium particles incorporating nano-scale data. The formulated model showed that palladium oxide in three different valence states displays a unique structure, forming aggregates with microscopic clusters of approximately 3 nm as the minimum units.


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Author (organization or company)

Tomohiro IKEDA(Automobile R&D Center)、Atsushi FURUKAWA(Automobile R&D Center)、Tatsuya OKAYAMA(Automobile R&D Center)、Hisao YOSHIDA(Kyoto University)

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