Morphology and Lateral Strain Control of Pt Nanoparticles via Core鈥揝hell Construction Using Alloy AgPd Core Toward Oxygen Reduction Reaction
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- 作者：Jinhua Yang ; Jun Yang ; Jackie Y. Ying
- 刊名：ACS Nano
- 出版年：2012
- 出版时间：November 27, 2012
- 年：2012
- 卷：6
- 期：11
- 页码：9373-9382
- 全文大小：843K
- 年卷期：v.6,no.11(November 27, 2012)
- ISSN：1936-086X
文摘
Controlling the morphology of Pt-based nanomaterials can be an effective way to improve the catalytic activity on a mass basis. Herein we demonstrate for the first time the synthesis of monodispersed core鈥搒hell AgPd@Pt nanoparticles with multiply twinned structures. These multiply twinned particles (MTPs), which possess the icosahedra structure, exhibit superior catalytic activity toward oxygen reduction reaction (ORR) in fuel cells. The Ag component of the alloy AgPd inner core is crucial for the construction of the multiply twinned structure of the core鈥搒hell nanoparticles, while the Pd component is used to reduce the tensile strain effect of the Ag on the deposited Pt layers, rendering the Pt binding energy in core鈥搒hell AgPd@Pt MTPs to be close to that of commercial Pt nanoparticles. The enhanced ORR activity of AgPd@Pt/C can be explained in terms of a much higher surface fraction of atoms on the (111) facets for icosahedral MTPs. This core鈥搒hell structure offers an interesting example to investigate the morphology and lateral strain effect of the substrate on the deposited layers, and their influence on the catalytic activity of metal catalysts.