MECHANISM OF THE DECOMPOSITION OF PT-CO BIMETALLIC PARTICLES IN NAY ZEOLITES

被引：19

作者：

GUCZI, L

SARKANY, A

KOPPANY, Z

机构：

[1] Department of Surface Chemistry and Catalysis, Institute of Isotopes, the Hungarian Academy of Sciences, Budapest, H-1525

来源：

APPLIED CATALYSIS A-GENERAL | 1994年 / 120卷 / 01期

关键词：

BIMETALLIC PARTICLES; DECOMPOSITION; PLATINUM COBALT; NAY ZEOLITES;

D O I：

10.1016/0926-860X(94)80329-3

中图分类号：

O64 [物理化学（理论化学）、化学物理学];

学科分类号：

070304 ; 081704 ;

摘要：

The decomposition mechanism of bimetallic particles encapsulated in the Pt-Co/NaY zeolite system is discussed. The large decrease in hydrogen uptake observed in TPR measurements taken before and after mild oxidation is interpreted in the light of the decomposition of bimetallic particles. During mild oxidation, Co2+ ions are first enriched on the surface of the bimetallic particles, then they become detached and migrate to the hexagonal or sodalite cages leaving Pt2+-covered Pt-0 kernels in the supercage. No agglomeration or migration of these kernels to the external surface was observed.

引用

页码：L1 / L5

页数：5

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