Thickness‐dependent high‐performance solid oxide fuel cells with Ba_0.5Sr_0.5Co_0.8Fe_0.2O_3‐δ cathode

Abstract

The electrochemical performance of solid oxide fuel cells (SOFCs) is highly reliant upon the properties of cathodes, including crystal structure, electrical conductivity, electrode thickness, and so on. Here, Ba 0.5 Sr 0.5 Co 0.8 Fe 0.2 O 3-δ (BSCF) is synthesized and served as the electrode for enabling highperformance SOFCs. The effect of electrode thickness on the electrocatalytic activity is systematically investigated. The electrode thickness is adjusted in two ways. One is spray-coating and then calcining once, and the other is performing the above process twice. On the basis of symmetrical cells configuration, the oxygen reduction reaction (ORR) activity of BSCF electrode with different thickness is evaluated and analyzed by the electrochemical impedance spectroscopy (EIS) technique and distribution of relaxation time (DRT).The obtained area-specific resistances (ASRs) of electrodes on the oxygen ion conducting electrolyte Sm 0.2 Ce 0.9 O 1.90 (SDC) demonstrate the thicknessdependent electrochemical activity in ORR of BSCF electrode. With an electrode thickness of 24 μm that controlled by conducting "spray-coating and calcining" twice, the BSCF electrode displays the optimal electrochemical performance with an ASR of 0.072 Ω cm 2 in ambient air at 600 C. This strategy has allowed us to produce an electrode layer with optimal thickness, paving a new path for the design of high-performance SOFCs.

High-Performance and Robust Composite Cathode via W Doping-Induced Phase Separation for Proton Ceramic Fuel Cells

“…As well-known, SrCoO 3−δ (SC)-based perovskite is seen as one of the most potential cathodes for SOFCs on account of the advantages of sufficiently high electronic and ionic conductivity and adequate activity for ORR. , In the past few years, some well-known SC-based perovskite-type materials possessing mixed electron conductivity and ion conductivity (MIEC), such as SmSrCoO 3−δ (SSC), La 0.6 Sr 0.4 Co 0.8 Fe 0.2 O 3−δ (LSCF), and Ba 0.5 Sr 0.5 Co 0.8 Fe 0.2 O 3−δ (BSCF), have demonstrated their potential as cathodes for O-SOFCs, while exhibiting dissatisfactory performance for PCFCs. − This is mainly due to the insufficient protonic conductivity. Later on, although developing some encouraging cathode materials, realizing widespread popularization and commercial application of PCFC technology is still of great difficulty. , …”

Enhanced ORR Activity of A-Site-Deficient SrCo0.8Nb0.1Ti0.1O3−δ as a Bifunctional Air Electrode for Low-Temperature Solid Oxide Fuel Cells

“…The MIEC allows the ORR active site to diffuse over the entire surface of the cathode to enhance ORR activity. − SrCoO 3−δ -based materials have received much attention owing to their superior oxygen ionic and electronic conductivity. Nevertheless, the chemical stability and thermal matching of these materials are not very satisfactory. − …”

Toward High Performance Mixed Ionic and Electronic Conducting Perovskite-Based Oxygen Permeable Membranes: An Overview of Strategies and Rationales

“…At 950 °C, the oxygen permeation flux of the membrane (1.5 mm) could reach 1.6 mL min –1 cm –2 under an air–He atmosphere . Since then, BSCF has aroused substantial interest. − Recently, many new and efficient OPMs have been developed, for instance, BaCo 1– x – y Fe x Zr y O 3‑δ , Ba 0.95 La 0.05 FeO 3‑δ , BaCo 0.7 Fe 0.2 Nb 0.1 O 3‑δ , and so on. − However, these membranes have relatively poor stability when their oxygen permeability reaches commercial requirements, and their oxygen permeability decreases when their stability increases, making it difficult to meet commercial standards. In recent years, scientific communities have developed substantial membrane modification strategies, aiming to improve the performance of OPMs. − Several reviews on high-performance OPMs have been published.…”