Electrokinetic Insights into the Triple Ionic and Electronic Conductivity of a Novel Nanocomposite Functional Material for Protonic Ceramic Fuel Cells. Issue 40 (4th September 2022)

• Record Type: Journal Article
• Authors: Bello, Idris Temitope; Yu, Na; Song, Yufei; Wang, Jian; Chan, Ting‐Shan; Zhao, Siyuan; Li, Zheng; Dai, Yawen; Yu, Jie; Ni, Meng
• Is Part Of: Small. Volume 18:Issue 40(2022)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2022-09-04
• Subjects: cathodes -- nanocomposites -- proton uptake mechanism -- protonic ceramic fuel cells -- self‐assembled -- triple ionic and electronic conductivity (TIEC); Nanotechnology -- Periodicals; Nanoparticles -- Periodicals; Microtechnology -- Periodicals; 620.5
• DOI: 10.1002/smll.202203207
• Languages: English
• ISSNs: 1613-6810

Abstract

Abstract: Triple ionic and electronic conductivity (TIEC) in cathode materials for protonic ceramic fuel cells (PCFCs) is a desirable feature that enhances the spatial expansion of active reaction sites for electrochemical oxygen reduction reaction. The realization of optimal TIEC in single‐phase materials, however, is challenging. A facile route that facilitates the optimization of TIEC in PCFC cathodes is the strategic development of multiphase cathode materials. In this study, a cubic‐rhombohedral TIEC nanocomposite material with the composition Ba(CeCo)0.4 (FeZr)0.1 O3− δ (BCCFZ) is designed via self‐assembly engineering. The material consists of a mixed ionic and electronic conducting phase, BaCo1−( x + y + z ) Ce x Fe y Zr z O3− δ (M‐BCCFZ), and a dominant proton‐conducting phase, BaCe1−( x + y + z ) Co x Zr y Fe z O3− δ (H‐BCCZF). The dominant cerium‐rich H‐BCCFZ phase enhances the material's oxygen vacancy concentration and the proton defects formation and transport with a low enthalpy of protonation of −30 ± 9 kJ mol −1 . The area‐specific resistance of the BCCFZ symmetrical cell is 0.089 Ω cm 2 at 650 °C in 2.5% H2 O‐air. The peak power density of the anode‐supported single cell based on BCCFZ cathode reaches 1054 mW cm −2 at 650 °C with good operation stability spanning over 500 h at 550 °C. These promote BCCFZ as a befitting cathode material geared toward PCFC commercialization. Abstract : The multiphase material developed through self‐assembly engineering exhibits a high oxygen vacancy concentration. This consequently enhances its proton defect formation and transport with a low enthalpy of protonation reaching −30 ± 9 kJ mol −1 . The peak power density of the single cell reaches 1054 mW cm −2 at 650 °C with good operation stability spanning over 500 h at 550 °C.