Abstract

When a platinum supported acidic support catalyst is used as a hydrocarbon purification catalyst for lean burn engines, it shows a high level of purification performance. In order to elucidate the causal factors, the surface state of the platinum particles was analyzed by an X-ray absorption near-edge structure analysis and ab-initio calculations, with a density functional theory using a large-scale cluster model and slab model, were carried out. The results showed that platinum particles retain a metallic state when acidic support is used. It was also found that there is a distribution of charge in the platinum particles, and when platinum atoms in proximity to the support are positively charged, they are in a state that tends to resist the adsorption of oxygen. It was found from these results that the high level of purification performance of acidic supported platinum is due to the electronic activity of the acidic support, which helps to prevent oxygen adsorption on the surface of platinum in proximity to the support so that the catalyst yields high activity with respect to paraffin.

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Author (organization or company)

• Yuichi MATSUO（Automobile R&D Center）
• Satoshi HIROSE（Automobile R&D Center）
• Hiroki TAKEORI（Automobile R&D Center）
• Tatsuya OKAYAMA（Automobile R&D Center）

Publication Information

Article of Honda R&D Technical Review Vol.31 No.1 (88 - 96)

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