Ba0.5Sr0.5Fe0.8Sb0.2O3-δ- Sm0.2Ce0.8O2-δ bulk heterostructure composite: A cobalt free Oxygen Reduction Electrocatalyst for low-temperature SOFCs. (9th November 2022)

• Record Type: Journal Article
• Authors: Lu, Yuzheng; Mushtaq, Naveed; Yousaf Shah, M.A.K.; Irshad, Muhammad Sultan; Rauf, Sajid; Yousaf, Muhammad; Zhu, Bin
• Is Part Of: International journal of hydrogen energy. Volume 47:Number 90(2022)
• Page Start: 38348
• Page End: 38360
• Publication Date: 2022-11-09
• Subjects: Sm0.2Ce0.8O2-δ-Ba0.5Sr0.5Fe0.8Sb0.2O3-δ -- Bulk heterostructure composite -- Co-free cathode material -- High oxygen-reduction reaction activity -- Low area-specific resistance -- LT-SOFC; Hydrogen as fuel -- Periodicals; Hydrogène (Combustible) -- Périodiques; Hydrogen as fuel; Periodicals; 665.81
• DOI: 10.1016/j.ijhydene.2022.09.009
• Languages: English
• ISSNs: 0360-3199

Abstract

Abstract: Low-temperature operated ceramic fuel cells (LT-CFCs 350° to 550 °C) hold a great promise than high-temperature solid oxide fuel cells (HT-SOFCs ≥ 800 °C) for numerous large-scale real-application. If a suitable cathode should be developed to overcome the sluggish oxygen reduction activity at low temperatures, the low-temperature operation of ceramic fuel cells could be possible. In this study, we have developed a cobalt-free Ba0.5 Sr0.5 Fe0.8 Sb0.2 O3-δ - Sm0.2 Ce0.8 O2-δ (BSFSb- SDC) a bulk heterostructure composite for efficient ORR electrocatalyst for LT-SOFC cathode. The established BSFSb-SDC bulk heterostructure composite exhibits large lattice parameters, very low-area-specific resistance, and high oxygen reduction reaction (ORR) activity at low operating temperatures. The prepared fuel cell device has demonstrated high-power densities of 890 mW-cm- 2 at 550 °C for button-sized SOFC on H2 and even possible operation at 400 °C. It is also found that BSFSb-SDC effectively facilitates small polaron hopping of valence electrons and diffusion of oxygen ions. Various spectroscopic measurements such as X-ray photoelectron, UV–visible, Raman, and Density Functional Theory (DFT) calculations were employed to understand the improved ORR electrocatalyst function of BSFSb-SDC bulk heterostructure composite SOFC cathode. The results can further help to develop functional cobalt-free electro-catalysts for LT-SOFCs and other related applications. Graphical abstract: Image 1 Highlights: BSFSb-SDC heterostructure composite cathode is developed for LT-SOFCs applications. BSFSb-SDC heterostructure shows a porous structure and excellent Oxygen reduction reaction (ORR) activity. The excellent electrochemical performance of 890 mW cm −2 is achieved at 550 °C . BSFSb-SDC shows very low mass and charge transfer losses of 0.07 and 0.45 Ωcm −2 at 550 °C .