Contribution of shape resonance and Pt-H EXAFS in the Pt L2,3 X-ray absorption edges of supported Pt particles:: Application and consequences for catalyst characterization

被引：83

作者：

Ramaker, DE ^{[1
]}

Mojet, BL

Oostenbrink, MTG

Miller, JT

Koningsberger, DC

机构：

[1] George Washington Univ, Dept Chem, Washington, DC 20052 USA

[2] Univ Utrecht, Dept Inorgan Chem & Catalysis, Debye Inst, NL-3508 TB Utrecht, Netherlands

[3] Amoco Corp, Amoco Res Ctr, Naperville, IL 60566 USA

来源：

PHYSICAL CHEMISTRY CHEMICAL PHYSICS | 1999年 / 1卷 / 09期

关键词：

D O I：

10.1039/a900716d

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 electronic and geometric effects induced by hydrogen chemisorption on small platinum particles supported on high surface-area saponite clay and zeolite LTL were studied by near edge X-ray absorption fine structure (XAFS) spectroscopy. A new subtraction procedure was developed to separate the electronic from geometric effects. A significant Pt-H extended X-ray absorption fine structure (EXAFS) scattering (structural effect) was found for energy values between 0 and 20 eV. In addition, the Pt-H antibonding state (electronic effect) was found to produce a shape-resonance and was isolated from the near edge of the L-3 X-ray absorption spectrum. Moreover, for Pt/LTL the shape and energy of the shape-resonance was found to strongly depend on the acidity/alkalinity of the support material, implying a direct influence of the support on the electronic properties of the platinum particles. The results of the study of the resonance state and the Pt-H EXAFS scattering demonstrate the potential of these techniques for characterization of hydrogen chemisorption, metal-promoter, and metal-support effects in catalysis research.

引用

页码：2293 / 2302

页数：10

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