title: TOF-SIMS characterization of impurity enrichment and redistribution in solid oxide electrolysis cells during operation.
abstract: TOF-SIMS analyses of state-of-the-art high temperature solid oxide electrolysis cells before and after testing under different operating conditions were performed. The investigated cells consist of an yttria stabilized zirconia (YSZ) electrolyte, a La1-xSrxMnO3-δ composite anode and a Ni-YSZ cermet cathode. The surfaces and cross-sections of the cells were analyzed, and several elemental impurities like Si, Ca and Na were identified and spatially mapped and their enrichment and migration during operation is reported. With advancing operation time, the concentration of these elements, especially Na and Ca, increases. For Si, a concentration gradient is found from the gas inlet to the gas outlet. Additionally, a loss of Ni percolation in the active cathode is observed in the same area where the Si enrichment is found. Based on the obtained TOF-SIMS results, the influence of the operating conditions on degradation is discussed.
authors.affiliation: Department of Energy Conversion and Storage, Technical University of Denmark, Risø Campus, Frederiksborgvej 399, DK-4000 Roskilde, Denmark. woki@dtu.dk.
authors.forename: Ragnar
authors.initials: R
authors.lastname: Kiebach
authors.forename: Kion
authors.initials: K
authors.lastname: Norrman
authors.forename: Christodoulos
authors.initials: C
authors.lastname: Chatzichristodoulou
authors.forename: Ming
authors.initials: M
authors.lastname: Chen
authors.forename: Xiufu
authors.initials: X
authors.lastname: Sun
authors.forename: Sune D
authors.initials: SD
authors.lastname: Ebbesen
authors.forename: Mogens B
authors.initials: MB
authors.lastname: Mogensen
authors.forename: Peter Vang
authors.initials: PV
authors.lastname: Hendriksen