Electrochemical ageing study of mixed lanthanum/praseodymium nickelates La2-PrNiO4+δ as oxygen electrodes for solid oxide fuel or electrolysis cells

Vaibhav Vibhu (1) , Aurelien Flura (1) , Aline Rougier (1) , Clément Nicollet (1) , Sébastien Fourcade (1) , Teresa Hungría (2) , Jean-Claude Grenier (1) , Jean-Marc. Bassat (1)

1 ICMCB - Institut de Chimie de la Matière Condensée de Bordeaux
2 Centre Castaing - Centre de microcaractérisation Raimond Castaing

The chemical and electrochemical stability of lanthanide nickelates La2NiO4+δ (LNO), Pr2NiO4+δ (PNO) and their mixed compounds La2-xPrxNiO4+δ (LPNOs) with x = 0.5, 1 or 1.5 is reported. The aim is to promote these materials as efficient electrodes for solid oxide fuel cell (SOFC) and/or solid oxide electrolysis cell (SOEC). La2NiO4+δ and La1.5Pr0.5NiO4+δ compounds are chemically very stable as powders over one month in the temperature range 600 − 800°C, while the other materials rich in praseodymium progressively decompose into various perovskite-deriving components with additional Pr6O11. Despite their uneven properties, all these materials are quite efficient and sustainable as electrodes on top of gadolinium doped ceria (GDCBL) // yttrium doped zirconia (8YSZ) electrolyte, for one month at 700°C without polarization. Under polarization (300 mA·cm−2), the electrochemical performances of LNO, PNO and La1.5Pr0.5NiO4+δ (LP5NO) quickly degrade in SOFC mode, i.e. for the oxygen reduction reaction, while they show durability in SOEC mode, i.e. for the oxide oxidation reaction.

Mots clés: Lanthanide nickelates; SOFC cathode; SOEC anode; Ageing; Degradation 2

Domaines: Matériaux

Vaibhav Vibhu, Aurelien Flura, Aline Rougier, Clément Nicollet, Sébastien Fourcade, et al.. Electrochemical ageing study of mixed lanthanum/praseodymium nickelates La2-PrNiO4+δ as oxygen electrodes for solid oxide fuel or electrolysis cells. Journal of Energy Chemistry, 2020, 46, pp.62-70. ⟨10.1016/j.jechem.2019.10.012⟩. ⟨hal-02354352⟩