Electronic properties and charge transfer phenomena in Pt nanoparticles on γ-Al2O3: size, shape, support, and adsorbate effects

被引：69

作者：

Behafarid, F. ^{[1
]}

Ono, L. K. ^{[1
]}

Mostafa, S. ^{[1
]}

Croy, J. R. ^{[1
]}

Shafai, G. ^{[1
]}

Hong, S. ^{[1
]}

Rahman, T. S. ^{[1
]}

Bare, Simon R. ^{[2
]}

Roldan Cuenya, B. ^{[1
]}

机构：

[1] Univ Cent Florida, Dept Phys, Orlando, FL 32816 USA

[2] Honeywell Co, UOP LLC, Des Plaines, IL 60017 USA

来源：

PHYSICAL CHEMISTRY CHEMICAL PHYSICS | 2012年 / 14卷 / 33期

基金：

美国能源部; 美国国家科学基金会;

关键词：

RAY-ABSORPTION SPECTROSCOPY; NEGATIVE THERMAL-EXPANSION; GAMMA-ALUMINA SURFACES; EDGE STRUCTURES XANES; HYDROGEN ADSORPTION; PARTICLE-SIZE; DISSOCIATIVE CHEMISORPTION; MICELLE ENCAPSULATION; PLATINUM CLUSTERS; VALENCE ORBITALS;

D O I：

10.1039/c2cp41928a

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：

This study presents a systematic detailed experimental and theoretical investigation of the electronic properties of size-controlled free and gamma-Al2O3-supported Pt nanoparticles (NPs) and their evolution with decreasing NP size and adsorbate (H-2) coverage. A combination of in situ X-ray absorption near-edge structure (XANES) and density functional theory (DFT) calculations revealed changes in the electronic characteristics of the NPs due to size, shape, NP-adsorbate (H-2) and NP-support interactions. A correlation between the NP size, number of surface atoms and coordination of such atoms, and the maximum hydrogen coverage stabilized at a given temperature is established, with H/Pt ratios exceeding the 1 : 1 ratio previously reported for bulk Pt surfaces.

引用

页码：11766 / 11779

页数：14

共 68 条

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