title: Three-dimensional reconstruction of a solid-oxide fuel-cell anode.
abstract: The drive towards increased energy efficiency and reduced air pollution has led to accelerated worldwide development of fuel cells. As the performance and cost of fuel cells have improved, the materials comprising them have become increasingly sophisticated, both in composition and microstructure. In particular, state-of-the-art fuel-cell electrodes typically have a complex micro/nano-structure involving interconnected electronically and ionically conducting phases, gas-phase porosity, and catalytically active surfaces. Determining this microstructure is a critical, yet usually missing, link between materials properties/processing and electrode performance. Current methods of microstructural analysis, such as scanning electron microscopy, only provide two-dimensional anecdotes of the microstructure, and thus limited information about how regions are interconnected in three-dimensional space. Here we demonstrate the use of dual-beam focused ion beam-scanning electron microscopy to make a complete three-dimensional reconstruction of a solid-oxide fuel-cell electrode. We use this data to calculate critical microstructural features such as volume fractions and surface areas of specific phases, three-phase boundary length, and the connectivity and tortuosity of specific subphases.
authors.affiliation: Department of Materials Science and Engineering, Northwestern University, Evanston, Illinois 60208, USA. jameswilson@northwestern.edu
authors.forename: James R
authors.initials: JR
authors.lastname: Wilson
authors.forename: Worawarit
authors.initials: W
authors.lastname: Kobsiriphat
authors.forename: Roberto
authors.initials: R
authors.lastname: Mendoza
authors.forename: Hsun-Yi
authors.initials: HY
authors.lastname: Chen
authors.forename: Jon M
authors.initials: JM
authors.lastname: Hiller
authors.forename: Dean J
authors.initials: DJ
authors.lastname: Miller
authors.forename: Katsuyo
authors.initials: K
authors.lastname: Thornton
authors.forename: Peter W
authors.initials: PW
authors.lastname: Voorhees
authors.forename: Stuart B
authors.initials: SB
authors.lastname: Adler
authors.forename: Scott A
authors.initials: SA
authors.lastname: Barnett