Role of Cathode Material GDC with B-Site-Substituted Bi <sub>0.5</sub> Sr <sub>0.5</sub> Fe <sub>0.9</sub> X <sub>0.1</sub> O <sub>3−δ</sub> (X = Nb, Sn, and Sb) Composites in Enhanced Electrochemical Performance of IT-SOFCs
This work presents a strategy for enhancing the performance of intermediate-temperature solid oxide fuel cell (IT–SOFC) cathodes by using GDC-based composites with Sn-, Nb-, and Sb-substituted Bi0.5Sr0.5FeO3−δ(BiSFO) as cathode material. This significantly improved oxygen ion transport and electrochemical performance. Among the composites, 70 wt % Sb-substituted BiSFO and 30 wt % GDC exhibited the highest power density (844 mW/cm2), current density (4210 mA/cm2), and lowest polarization resistance (0.031 Ω·cm2) due to enhanced oxygen vacancy concentration and mixed Sb valence. Detailed electrochemical impedance spectroscopy and distribution of relaxation and time analysis revealed dominant intermediate-frequency processes linked to oxygen surface exchange and bulk diffusion. The GDC phase also promoted an improved triple-phase boundary activity and ionic conduction. The synergistic effect of B-site substituents and GDC composite design enabled cobalt-free cathodes with improved oxygen transport and promising thermal compatibility for IT-SOFC cathodes.
Authors
- R.S. Gedam (ORCID: https://orcid.org/0000-0002-7744-1600)
- Oroosa Subohi (ORCID: https://orcid.org/0000-0001-9642-4630)
- Suddhasatwa Basu (ORCID: https://orcid.org/0000-0001-7288-2370)
- Vicky Dhongde (ORCID: https://orcid.org/0000-0003-0732-8204)
- Isha Bhasin (ORCID: https://orcid.org/0009-0009-0202-7323)
- Gitesh I. Choudhari
Institutions
- Visvesvaraya National Institute of Technology (IN)
- Indian Institute of Technology Delhi (IN)
Publication Details
- Journal
- ACS Applied Energy Materials
- Published
- 2025-10-17
- DOI
- https://doi.org/10.1021/acsaem.5c02610
- Primary Topic
- Advancements in Solid Oxide Fuel Cells
- Type
- article
- Field-Weighted Citation Impact
- 0.00