High-performance BaZr0.1Ce0.7Y0.1Yb0.1O3-δ (BZCYYb) protonic ceramic fuel cell electrolytes by the Ba evaporation inhibition strategy

• Published in: Ceramics international Vol. 50; no. 2; pp. 3633 - 3640
• Main Authors: Zhong, Zhaoyu, Song, Tao, Zhao, Shikai, Sun, Haibin, Guo, Xue, Feng, Yurun, Hu, Qiangqiang
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 15.01.2024
• Subjects: Barium cerate; Grain boundary; Protonic ceramic fuel cell; Space-charge layer; Protonic ceramic fuel cell; Space-charge layer; Barium cerate; Grain boundary
• ISSN: 0272-8842
• DOI: 10.1016/j.ceramint.2023.11.113

BaZr0.1Ce0.7Y0.1Yb0.1O3-δ (BZCYYb) as a potential candidate for protonic ceramic fuel cells (PCFCs) electrolytes, often suffers from its high sintering temperature, making it deviate from the stoichiometric ratio and present a poor electrochemical performance than expected. Here, we reported a Ba evaporation inhibition strategy to fabricate stoichiometric BZCYYb electrolyte. By using this strategy, Ba evaporation and Y2O3/Yb2O3 segregation can be effectively suppressed. The electrolyte's average grain size is ∼5.29 μm, significantly promoting grain growth. An improvement of 60 % in total conductivity is accomplished at 700 °C in humid air, approaching 2.7 × 10−2 S cm−1. By constructing the proton transport model, the reasons for the enhanced electrochemical performance are explained from both bulk and grain boundary. Finally, at 700 °C, an anode-supported single cell with stoichiometric BZCYYb electrolyte demonstrates a maximum power density of 0.65 W cm−2, showing that the barium evaporation inhibition strategy is a powerful tool to fabricate PCFCs with high performance. •Stoichiometric BZCYYb electrolyte is obtained by a Ba evaporation inhibition strategy.•Large grain size (∼5.29 μm) of BZCYYb electrolyte is obtained.•Enhanced electrical conductivity reaches to 2.7 × 10−2 S cm−1 at 700 °C in humid air.