Effect of High-Temperature Exposure on Degradation of La0.6Sr0.4CoO3 Coated Metallic Interconnects for ITSOFC and SOEC

Matias de Angelis Korb (1, 2) , Diego Pereira Tarragó (1) , Cesar Augusto Krischer (1) , Sandrine Nathalie Duluard (3) , Florence Ansart (3) , Célia de Fraga Malfatti (1)

1 UFRGS - Universidade Federal do Rio Grande do Sul [Porto Alegre]
2 IFSUL - Instituto Federal Sul-rio-grandense [Passo Fundo]
3 CIRIMAT - Centre interuniversitaire de recherche et d'ingenierie des matériaux

Previous studies showed the formation of new phases affecting the electrical properties of LSC thin films deposited on stainless steel substrates, which are commonly tested for ITSOFC and SOEC interconnects. A 4.3 μm thick La0.6Sr0.4CoO3 coating was deposited on AISI430 steel by spray pyrolysis, followed by heat treatment (800°C/2h) and an oxidation in air (800°C/96h). The La0.6Sr0.4CoO3 phase interacted with the metallic substrate and formed SrCrO4, causing degradation of the perovskite into La0.9Sr0.1CoO3. An EDS mapping showed Sr and Cr enrichment in the coating/substrate interface. TG analysis indicated a lower mass gain for the coated substrate. The total ASR at 800°C of the interconnect before and after oxidation was 3.23 Ω.cm2 and 3.98 Ω.cm2, respectively. The Ea underwent very small variation, remaining around 0.24 eV (T≤300°C) and 0.65 eV (T≥400°C). The reaction of Cr from the substrate and Sr from LSC seems to have impaired the performance of the interconnect.

Mots clés: Steel intreconnect; Coating; Lanthanum cobaltite; Impedance spectroscopy

Domaines: Matériaux

Matias de Angelis Korb, Diego Pereira Tarragó, Cesar Augusto Krischer, Sandrine Nathalie Duluard, Florence Ansart, et al.. Effect of High-Temperature Exposure on Degradation of La0.6Sr0.4CoO3 Coated Metallic Interconnects for ITSOFC and SOEC. Materials Research, 2020, 23 (3), pp.1-7. ⟨10.1590/1980-5373-MR-2020-0084⟩. ⟨hal-03170651⟩