Symmetric electrodes for solid oxide fuel cells based on Zr-doped SrFeO3−δ

Sucrose-Assisted Solution Combustion Synthesis of Doped Strontium Ferrate Perovskite-Type Electrocatalysts: Primary Role of the Secondary Fuel

“…Among the three samples under study, SCFC-SPx has a higher symmetrical behavior than SCFC-S and SCFC-SP20 is the most symmetrical one. Therefore, oxygen evolution is slightly favored in comparison with the oxygen reduction and this indicates a good behavior of the materials also as anode for IT-SOFC, as highlighted in the literature [37,43,67]. The commercial specimen shows the highest performances with the lowest overpotentials achieved i.e., −0.4 A cm −2 at −0.34 V for the reduction reaction and 0.4 A cm −2 at 0.34 V for the evolution reaction of oxygen (Figure 7a).…”

“…The perovskite structure formation depends on the relative A-site and B-site cation radius according to the Goldsmith tolerance factor, which is the most widely recognized criterion [28]. Electrocatalysts with ABO 3 structure found application as electrode materials for electrochemical devices like Intermediate Temperatures Solid Oxide Fuel Cells (IT-SOFC) [29][30][31][32][33][34], Symmetrical Solid Oxide Fuel Cells (SSOFCs) [35][36][37], and electrolyzers [35,38,39]. The main requirements of electrode materials are (i) to be able to adsorb oxygen from the air and catalytically reduce it (oxygen reduction reaction) or to evolve oxygen and catalytically oxidize the fuel (oxygen evolution reaction), (ii) to possess high mixed ionic and electronic conductivity, (iii) to be highly compatible with the electrolyte in terms of thermal expansion coefficient (TEC), to avoid detrimental effects on the performances and failures in long-term operations.SrFeO 3-δ is a perovskite-type mixed oxide where iron has the expected oxidation state of +4, whereas in most ABO 3 perovskites, like pure and doped LaFeO 3 , the common oxidation state at B-site is +3 [38].…”

Pr and Ti co-doped Strontium Ferrite as a Novel Hydrogen Electrode for Solid Oxide Electrolysis Cell

“…angle, which can be explained as cell expansion (a=3.9021±0.0016 Å, V=59.4172±0.0748 Å 3 ) resulted from the transition of Fe 4+ (0.585 Å) to Fe 3+ (0.645 Å) and/or Ti 4+ (0.605 Å) to Ti 3+ (0.670 Å)[24,25]. As reported in the literature[26], a phase transformation from SrFeO 3−δ to Sr 2 Fe 2 O 5 occurred after annealing in a flow of 5%H 2 /Ar at 800 °C for 24 h. In comparison, PSTF shows much better at phase stability in reducing atmosphere.The mixed conductivity of PSTF is 0.25 S cm −1 at 800 °C in 5%H 2 /N 2 . It is significantly higher than that of pure SrFeO 3 in 5%H 2 /Ar at 800 °C, e.g.…”

Advances in electrode materials for Li-based rechargeable batteries

“…210 Symmetric electrodes have also been assembled and demonstrated in supercapacitors, 211 fuel cells, 212 and in redox ow batteries with the attempt to avoid cross-contamination of active species. [213][214][215][216] 4.5 Semi-solid Li-ow batteries Although signicant advances in electrochemical energy storage devices, development of low-cost and high energy density system remains a challenge, especially for medium-and large-scale applications.…”