Structural and Electrochemical Analysis of SmBa0.8Sr0.2Co2O5+δ Cathode Oxide for IT-SOFCs

Abstract

The double perovskite SmBa0.8Sr0.2Co2O5+δ(SBSC82)wasprepared using a conventional techniqueand evaluatedas solid oxide fuel cells (SOFCs) cathode materialwhich operatesat intermediate temperatures. The SBSC82 cathode powder was produced using the solid-state reaction technique and an alumina ball as a grinder. XRD was used to determine the cathode powder structure, and the microstructure was analyzed using SEM.The oxygen content (δ) for the SBSC82 cathode was recorded by a thermogravimetric analyzer.Powder patterns and lattice parameters weredetected using General Structure Analysis System (GSAS) software. The symmetrical cell was examined using a Voltalab PGZ 301 potentiostat. The δ of SBSC82 cathode reached5.68, 5.43, and 5.22 at 400oC, 600oC, and 800oC.It was found that SBSC82 oxide showasa simple perovskite-type structure with tetragonal P4/mmm.The polarization resistance (Rp) of the symmetrical cell with SDC|SBCS82|SDC configuration reached of 0.420Ω.cm2, 0.091 Ω.cm2,and 0.041 Ω.cm2at 650oC, 750oC, and 850oC, respectively.Single cell specimen achieves a power density of 377 mW/cm2under humidified air/hydrogen.

Progress in Developing LnBaCo2O5+δ as an Oxygen Reduction Catalyst for Solid Oxide Fuel Cells

“…Kim et al [86] observed improved chemical stability when GDC and LSGM electrolytes are used. Numerous investigations have systematically examined the electrical and electrochemical properties of the LnBa 1−x Sr x Co 2 O 5+δ system, with Ln representing La 3+ [73], Pr 3+ [87,92], Nd 3+ [90,91], Sm 3+ [87][88][89]112,114], and Gd 3+ [85][86][87]111]. Kim et al [86] demonstrated that the electrical conductivity of GdBa 1−x Sr x Co 2 O 5+δ increases with rising Sr content, attributed to increased oxygen content, which is believed to be linked to the difference in A-site cation radii between (Ba 1−x Sr x ) 2+ and Gd 3+ .…”