CaltechAUTHORS
  A Caltech Library Service

Robust nanostructures with exceptionally high electrochemical reaction activity for high temperature fuel cell electrodes

Jung, WooChul and Gu, Kevin L. and Choi, Yoonseok and Haile, Sossina M. (2014) Robust nanostructures with exceptionally high electrochemical reaction activity for high temperature fuel cell electrodes. Energy and Environmental Science, 7 (5). pp. 1685-1692. ISSN 1754-5692. https://resolver.caltech.edu/CaltechAUTHORS:20140603-133823110

[img]
Preview
PDF - Published Version
See Usage Policy.

735Kb

Use this Persistent URL to link to this item: https://resolver.caltech.edu/CaltechAUTHORS:20140603-133823110

Abstract

Metal nanoparticles are of significant importance for chemical and electrochemical transformations due to their high surface-to-volume ratio and possible unique catalytic properties. However, the poor thermal stability of nano-sized particles typically limits their use to low temperature conditions (<500 °C). Furthermore, for electrocatalytic applications they must be placed in simultaneous contact with percolating ionic and electronic current transport pathways. These factors have limited the application of nanoscale metal catalysts (diameter <5 nm) in solid oxide fuel cell (SOFC) electrodes. Here we overcome these challenges of thermal stability and microstructural design by stabilizing metal nanoparticles on a scaffold of Sm_(0.2)Ce_(0.8)O_(2−δ) (SDC) films with highly porous and vertically-oriented morphology, where the oxide serves as a support, as a mixed conducting transport layer for fuel electro-oxidation reactions, and as an inherently active partner in catalysis. The SDC films are grown on single crystal YSZ electrolyte substrates by means of pulsed-laser deposition, and the metals (11 μg cm^(−2) of Pt, Ni, Co, or Pd) are subsequently applied by D.C. sputtering. The resulting structures are examined by TEM, SIMS, and electron diffraction, and metal nanoparticles are found to be stabilized on the porous SDC structure even after exposure to 650 °C under humidified H_2 for 100 h. A.C. impedance spectroscopy of the metal-decorated porous SDC films reveals exceptionally high electrochemical reaction activity toward hydrogen electro-oxidation, as well as, in the particular case of Pt, coking resistance when CH_4 is supplied as the fuel. The implications of these results for scalable and high performance thin-film-based SOFCs at reduced operating temperature are discussed.


Item Type:Article
Related URLs:
URLURL TypeDescription
http://dx.doi.org/10.1039/c3ee43546f DOIArticle
http://pubs.rsc.org/en/Content/ArticleLanding/2014/EE/c3ee43546fPublisherArticle
ORCID:
AuthorORCID
Haile, Sossina M.0000-0002-5293-6252
Additional Information:© 2014 The Royal Society of Chemistry. Received 26th October 2013; Accepted 12th February 2014. First published online 12 Feb 2014. This work was supported in part by the Stanford Global Climate Energy Program, by the National Science Foundation under contract number DMR 08-43934, and by Liox, Inc. Additional support was provided by the National Science Foundation through the Caltech Center for the Science and Engineering of Materials, a Materials Research Science and Engineering Center (DMR 05-20565) and by the National Research Foundation of Korea through its support for the Center for Multiscale Energy System, a Global Frontier R&D Program of the Ministry of Science, ICT & Future (2011-0031569).
Funders:
Funding AgencyGrant Number
Stanford Global Climate Energy ProgramUNSPECIFIED
NSFDMR 08-43934
Liox, Inc.UNSPECIFIED
NSFDMR 05-20565
National Research Foundation of Korea (NRF)UNSPECIFIED
Center for Multiscale Energy SystemUNSPECIFIED
Global Frontier R&D Program of the Ministry of Science, ICT Future2011-0031569
Issue or Number:5
Record Number:CaltechAUTHORS:20140603-133823110
Persistent URL:https://resolver.caltech.edu/CaltechAUTHORS:20140603-133823110
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:46051
Collection:CaltechAUTHORS
Deposited By: Tony Diaz
Deposited On:03 Jun 2014 20:55
Last Modified:03 Oct 2019 06:40

Repository Staff Only: item control page