title: A Stability Study of Ni/Yttria-Stabilized Zirconia Anode for Direct Ammonia Solid Oxide Fuel Cells.
abstract: In recent years, solid oxide fuel cells fueled with ammonia have been attracting intensive attention. In this work, ammonia fuel was supplied to the Ni/yttria-stabilized zirconia (YSZ) cermet anode at 600 and 700 °C, and the change of electrochemical performance and microstructure under the open-circuit state was studied in detail. The influence of ammonia exposure on the microstructure of Ni was also investigated by using Ni/YSZ powder and Ni film deposited on a YSZ disk. The obtained results demonstrated that Ni in the cermet anode was partially nitrided under an ammonia atmosphere, which considerably roughened the Ni surface. Moreover, the destruction of the anode support layer was confirmed for the anode-supported cell upon the temperature cycling test between 600 and 700 °C because of the nitriding phenomenon of Ni, resulting in severe performance degradation.
authors.affiliation: Department of Energy and Hydrocarbon Chemistry, Graduate School of Engineering, Kyoto University , Kyoto 615-8510, Japan.
authors.forename: Jun
authors.initials: J
authors.lastname: Yang
authors.affiliation: Department of Energy and Hydrocarbon Chemistry, Graduate School of Engineering, Kyoto University , Kyoto 615-8510, Japan.
authors.forename: Ahmed Fathi Salem
authors.initials: AF
authors.lastname: Molouk
authors.affiliation: Department of Energy and Hydrocarbon Chemistry, Graduate School of Engineering, Kyoto University , Kyoto 615-8510, Japan.
authors.forename: Takeou
authors.initials: T
authors.lastname: Okanishi
authors.affiliation: Department of Energy and Hydrocarbon Chemistry, Graduate School of Engineering, Kyoto University , Kyoto 615-8510, Japan.
authors.forename: Hiroki
authors.initials: H
authors.lastname: Muroyama
authors.affiliation: Department of Energy and Hydrocarbon Chemistry, Graduate School of Engineering, Kyoto University , Kyoto 615-8510, Japan.
authors.forename: Toshiaki
authors.initials: T
authors.lastname: Matsui
authors.affiliation: Department of Energy and Hydrocarbon Chemistry, Graduate School of Engineering, Kyoto University , Kyoto 615-8510, Japan.
authors.forename: Koichi
authors.initials: K
authors.lastname: Eguchi
keywords: Ni/yttria-stabilized zirconia anode; ammonia; degradation; nickel nitride; solid oxide fuel cells; stability