Temperature programmed oxygen desorption and sorption processes on Pr2-XLaxNiO4+δ nickelates

Alexandra Usenka (1) , Vladimir V. Pankov (1) , Vaibhav Vibhu (2) , Aurelien Flura (2) , Jean-Claude Grenier (2) , Jean-Marc. Bassat (2)

1 Institute of General of Inorganic Chemistry
2 ICMCB - Institut de Chimie de la Matière Condensée de Bordeaux

The present work is devoted to the investigation of temperature programmed oxygen desorption - sorption (TPD) processes performed on SOFC innovative cathode materials with Pr2-xLaxNiO4+δ composition. The experiments were performed using the coulometric titration technique involving an OXYLYT™ device, over the temperature cycle 20 – 900 – 20 °C. The considered parameters were the time and temperature dependences of both the titration current and the oxygen over-stoichiometry. TPD spectra of Pr2-xLaxNiO4+δ (x ≠ 0) exhibited two sharp peaks (maxima) of titration current with excellent resolution at p(O2) = 50 Pa, induced by removal of oxygen from different sites of the crystal lattice. TPD spectrum of Pr2NiO4+δ recorded under the same conditions drastically differs from the spectra of Pr2-xLaxNiO4+δ as four sharp maxima of titration current are detected. The TPD spectra of Pr2-xLaxNiO4+δ then strongly depend on the nature of the rare-earth (La or Pr) in link with the oxygen over-stoichiometry amount.

Domaines: Matériaux

Alexandra Usenka, Vladimir V. Pankov, Vaibhav Vibhu, Aurelien Flura, Jean-Claude Grenier, et al.. Temperature programmed oxygen desorption and sorption processes on Pr2-XLaxNiO4+δ nickelates. ECS Transactions, 2019, 91 (1), pp.1341-1353. ⟨10.1149/09101.1341ecst⟩. ⟨hal-02337219⟩