Electrochemical behaviour of propane-fed solid oxide fuel cells based on low Ni content anode catalysts

✍ Scribed by M. Lo Faro; D. La Rosa; I. Nicotera; V. Antonucci; A.S. Aricò

• Publisher: Elsevier Science
• Year: 2009
• Tongue: English
• Weight: 862 KB
• Volume: 54
• Category: Article
• ISSN: 0013-4686
• DOI: 10.1016/j.electacta.2009.03.077

✦ Synopsis

Two different low Ni content (10 wt.%) anode catalysts were investigated for intermediate temperature (800 • C) operation in solid oxide fuel cells fed with dry propane. Both catalysts were prepared by the impregnation of a Ni-precursor on different oxide supports, i.e. gadolinia doped ceria (CGO) and La 0.6 Sr 0.4 Fe 0.8 Co 0.2 O 3 perovskite, and thermal treated at 1100 • C for 2 h. The Ni-modified perovskite catalyst was mixed with a CGO powder and deposited on a CGO electrolyte to form a composite catalytic layer with a proper triple-phase boundary. Anode reduction was carried out in-situ in H 2 at 800 • C for 2 h during cell conditioning. Electrochemical performance was recorded at different times during 100 h operation in dry propane. The Ni-modified perovskite showed significantly better performance than the Ni/CGO anode. A power density of about 300 mW cm -2 was obtained for the electrolyte supported SOFC in dry propane at 800 • C. Structural investigation of the composite anode layer after SOFC operation indicated a modification of the perovskite structure and the occurrence of a La 2 NiO 4 phase. The occurrence of metallic Ni in the Ni/CGO system caused catalyst deactivation due to the formation of carbon deposits.