Elucidating the electronic structure of supported gold nanoparticles and its relevance to catalysis by means of hard X-ray photoelectron spectroscopy

SURFACE SCIENCE

卷:650

Article

Reinecke, Benjamin N.¹  Kuhl, Kendra P.¹  Ogasawara, Hirohito³  Li, Lin²  Voss, Johannes³  Abild-Pedersen, Frank³  Nilsson, Anders³  Jaramillo, Thomas F.^1,2,3 

[1] Stanford Univ, Dept Chem Engn, Shriram Ctr, 443 Via Ortega, Stanford, CA 94305 USA

[2] Stanford Univ, SUNCAT Ctr Interface Sci & Catalysis, Stanford, CA 94305 USA

[3] SLAC Natl Accelerator Lab, SUNCAT Ctr Interface Sci & Catalysis, 2575 Sand Hill Rd, Menlo Pk, CA 94025 USA

关键词: Gold nanoparticles;    Transmission electron microscopy;    Valence band;    Support effect;    Titanium dioxide;    Hard X-ray photoelectron spectroscopy;   

DOI  :  10.1016/j.susc.2015.12.025

来源: Elsevier

【 摘 要 】

We report on the electronic structure of Au (gold) nanoparticles supported onto TiO2 with a goal of elucidating the most important effects that contribute to their high catalytic activity. We synthesize and characterize with high resolution transmission electron microscopy (HRTEM) 3.4, 5.3, and 9.5 nm diameter TiO2-supported Au nanoparticles with nearly spherical shape and measure their valence band using Au 5d subshell sensitive hard X-ray photoelectron spectroscopy (HAXPES) conducted at Spring-8. Based on density functional theory (DFT) calculations of various Au surface structures, we interpret the observed changes in the Au 5d valence band structure as a function of size in terms of an increasing percentage of Au atoms at corners/edges for decreasing particle size. This work elucidates how Au coordination number impacts the electronic structure of Au nanoparticles, ultimately giving rise to their well-known catalytic activity. (C) 2015 Published by Elsevier B.V.

【 授权许可】

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