Issue 18, 2013

First principles computational study on the electrochemical stability of Pt–Co nanocatalysts

Abstract

Using density functional theory (DFT) calculations, we identify the thermodynamically stable configurations of Pt–Co alloy nanoparticles of varying Co compositions and particle sizes. Our results indicate that the most thermodynamically stable structure is a shell-by-shell configuration where the Pt atom only shell and the Co only shell alternately stack and the outermost shell consists of a Pt skin layer. DFT calculations show that the structure has substantially higher dissolution potential of the outermost Pt shell compared with pure Pt nanoparticles of approximately the same size. Furthermore, our DFT calculations also propose that the shell-by-shell structure shows much better oxygen reduction reaction (ORR) activity than conventional bulk or nanoparticles of pure Pt. These novel catalyst properties can be changed when the surfaces are adsorbed with oxygen atoms via selective segregation followed by the electrochemical dissolution of the alloyed Co atoms. However, these phenomena are thermodynamically not plausible if the chemical potentials of oxygen are controlled below a certain level. Therefore, we propose that the shell-by-shell structures are promising candidates for highly functional catalysts in fuel cell applications.

Graphical abstract: First principles computational study on the electrochemical stability of Pt–Co nanocatalysts

Article information

Article type
Paper
Submitted
20 May 2013
Accepted
04 Jul 2013
First published
05 Jul 2013

Nanoscale, 2013,5, 8625-8633

First principles computational study on the electrochemical stability of Pt–Co nanocatalysts

S. H. Noh, M. H. Seo, J. K. Seo, P. Fischer and B. Han, Nanoscale, 2013, 5, 8625 DOI: 10.1039/C3NR02611F

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements