Effect of chromium doping on structural development and electrical properties of LaNiO3 perovskites

• Published in: Journal of electroceramics Vol. 51; no. 4; pp. 281 - 291
• Main Authors: Borcezi, Janaina Semanech, Ramos, Kethlinn, de Oliveira Ouba, Ana Kaori, Chinelatto, Adriana Antonio Scoton, Grzebielucka, Edson Cezar, Monteiro, Francielli Casanova, Monteiro, João Frederico Hass Leandro, Wendler, Leonardo Pacheco, Chinelatto, Adilson Luiz
• Format: Journal Article
• Language: English
• Published: New York Springer US 01-12-2023; Springer Nature B.V
• Subjects: Catalytic activity; Cell anodes; Ceramics; Characterization and Evaluation of Materials; Chemistry and Materials Science; Chromium; Composites; Composition; Crystallography and Scattering Methods; Electrical properties; Electrochemistry; Electrode materials; Energy value; Fuel cells; Glass; Lanthanum oxides; Materials Science; Natural Materials; Optical and Electronic Materials; Oxidizing atmospheres; Perovskite structure; Perovskites; Sintering (powder metallurgy); Stability analysis; Structural stability; IT-SOFCs; Electrical conductivity; Pechini synthesis; Perovskite electrodes; Structural analysis
• ISSN: 1385-3449; 1573-8663
• DOI: 10.1007/s10832-023-00336-8

Perovskite-type oxides (ABO
3
) are potential alternatives as electrode materials for IT-SOFC. Their properties of electronic conduction, catalytic activity, and stability in oxidative and reductive atmospheres arouse this interest. Due to their electronic conduction properties, both LaNiO
3
perovskites, commonly used as a cathode, and LaCrO
3
perovskites, commonly used as interconnectors, can also be developed to be used as an anode. Thus, this work describes the results of experiments carried out on Cr-doped LaNiO
3
compositions aiming at their use as fuel cell anodes. The compositions of LaNi
1 − x
Cr
x
O
3
(0 ≤ x ≤ 0.7) were synthesized by a modified Pechini method, and the effects of replacing Ni with Cr in LaNiO
3
, mainly perovskite phase formation and structural stability, beyond microstructure and electrical properties were analyzed. Phases with a perovskite-like structure were obtained via calcination at 900 °C. For the sintered samples, it was observed that an increase in the amount of Cr led to an increase in porosity. The compositions with x = 0.7 and x = 0.5 sintered at 1300 and 1400 °C remained single-phase after sintering, while the composition x = 0.3 sintered at 1500 °C and the composition x = 0.0 sintered at 1250 °C decomposed into secondary phases. Concerning electrical properties, the activation energy values obtained were consistent with electronic conductivity, 0.03 eV, indicating p-type conduction in an oxidizing atmosphere.