Characterization of the high temperature properties of BaCe 0.4 Zr 0.4 Pr 0.2 O 3−δ perovskite as a potential material for PC-SOFCs

BASBUS, JUAN; ARCE, MAURICIO; TROIANI, HORACIO; PRADO, FERNANDO; MOGNI, LILIANA; SERQUIS, ADRIANA

NEW JOURNAL OF CHEMISTRY

ROYAL SOC CHEMISTRY

Año: 2021 vol. 45 p. 12957 - 12965

1144-0546

Compounds based on barium cerates and zirconates, Ba(Ce,Zr)O3d, are oxides able to transportprotons through their crystal lattice by proton hopping between oxygen sites. This feature makes thempotential candidates as electrolytes for proton conducting solid oxide fuel cells (PC-SOFCs). Pr-dopingthis family of compounds decreases sintering temperature and introduces electronic conductivity. Thiswork presents a systematic study of the high temperature properties of BaCe0.4Zr0.4Pr0.2O3d (BCZP)perovskite in view of its potential application as a PC-SOFC cathode. At room temperature, BCZPpresents as a rhombohedral structure, which transforms reversibly to cubic at 550 1C in dry air. Electricalmeasurements under dry and wet air with water vapor (B2% H2O) and heavy water vapor (B2% D2O)were employed to study the conductivity over a wide temperature range. The total conductivity dataexhibit behavior changes between 400 and 600 1C which could be associated with a crystal structuretransition. BCZP presents low total conductivity (64 mS cm1 at 600 1C), which limits its application assingle phase cathode material. However, the material has good thermomechanical compatibility withelectrolytes (B11 106 K1) and high CO2 tolerance (T 4 900 1C). These properties suggest that thiscompound could be used as an oxide support for composite, or backbone for impregnated, electrodes,or as a buffer layer to avoid degradation mechanisms improving the performance of another cathode