Pd segregation to the surface of bimetallic Pt-Pd particles supported on H-β zeolite evidenced with X-ray photoelectron spectroscopy and argon cation bombardment

被引：50

作者：

Fiermans, L

De Gryse, R

De Doncker, G

Jacobs, PA

Martens, JA

机构：

[1] Katholieke Univ Leuven, Ctr Oppervlaktech Katalyse, B-3001 Heverlee, Belgium

[2] State Univ Ghent, Vakgrp Vaste Stofwetenschappen, B-9000 Ghent, Belgium

来源：

JOURNAL OF CATALYSIS | 2000年 / 193卷 / 01期

关键词：

hydrocracking catalyst; bimetallic; platinum; palladium; beta zeolite; X-ray photoelectron spectroscopy; argon bombardment; surface segregation;

D O I：

10.1006/jcat.2000.2868

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：

Bimetallic PtPd/H-beta hydrocracking catalyst samples with 1.75 and 3.5 wt% metals, Pt:Pd atomic ratio of 3:1, and metal particle size of 1.7 nm were prepared using impregnation and cation exchange of Pt2+ and Pd2+ tetrammine complexes, oxidation, and hydrogen reduction at 400 degrees C. The dispersed metal phases were characterized using XPS, The formation of bimetallic Pt-Pd particles with segregation of the palladium to the particles surfaces was evidenced by intensity changes of the Pd 3d and Pt 4d photolines upon bombardment with argon cations and by comparison with a physical mixture of monometallic Pd/H-beta and Pt/H-beta catalysts, subjected to the same treatment. (C) 2000 Academic Press.

引用

页码：108 / 114

页数：7

共 16 条

[1] REEVALUATION OF X-RAY ATOMIC ENERGY LEVELS [J].