Details

Autor(en) / Beteiligte

• Ren, Rongzheng
• Wang, Zhenhua
• Xu, Chunming
• Sun, Wang
• Qiao, Jinshuo
• Rooney, David W
• Sun, Kening

Titel

Tuning the defects of the triple conducting oxide BaCoFeZrYO perovskite toward enhanced cathode activity of protonic ceramic fuel cells

Ist Teil von

• Journal of materials chemistry. A, Materials for energy and sustainability, 2019-08, Vol.7 (31), p.18365-18372

Erscheinungsjahr

2019

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• Protonic ceramic fuel cells (PCFCs) have interesting potential to efficiently produce electrical power from fuels in a low-temperature range (<650 °C). However, the sluggish activity of the oxygen reduction reaction is one of the greatest obstacles to the development of PCFCs. Single-phase triple-conducting (e − /O 2− /H + ) oxides are considered to be the most promising candidates for highly active PCFC cathodes because they can extend the electrochemically active sites to the entire cathode surface. Here, A-site deficiency of perovskite is introduced to tune the triple-conducting properties, which can stimulate the generation of oxygen vacancies and increase the oxygen-ion bulk diffusion and proton hydration kinetics. The so-obtained A-site-deficient perovskite oxides, Ba x Co 0.4 Fe 0.4 Zr 0.1 Y 0.1 O 3− δ ( x = 1, 0.95, 0.9), exhibit area specific resistance values of 1.61, 0.94, and 0.52 Ω cm 2 for BaCo 0.4 Fe 0.4 Zr 0.1 Y 0.1 O 3− δ , Ba 0.95 Co 0.4 Fe 0.4 Zr 0.1 Y 0.1 O 3− δ , and Ba 0.9 Co 0.4 Fe 0.4 Zr 0.1 Y 0.1 O 3− δ , respectively, at 500 °C in wet air ( p H 2 O = 0.1 atm). Peak power densities of 797.47, 668.64, 548.07, and 376.27 mW cm −2 are obtained from the PCFC with the Ba 0.9 Co 0.4 Fe 0.4 Zr 0.1 Y 0.1 O 3− δ cathode at 650, 600, 550 and 500 °C, respectively. Such remarkable performance demonstrates that introducing A-site deficiency is an effective strategy to enhance the triple-conducting properties of perovskite oxides for the high-activity cathode of PCFCs. Ba deficiency is used to tune the electronic, oxygen-ion and proton conduction in BaCo 0.4 Fe 0.4 Zr 0.1 Y 0.1 O 3− δ perovskite for a high-activity cathode of PCFCs.