Preparation of SmBa_0.5Sr_0.5Fe_2-XZn_XO_5+δ Nanofiber-Based Cathodes for Their Application in Solid Oxide Fuel Cells

In this paper, the Fe-based double perovskite-type oxide SmBa 0.5 Sr 0.5 Fe 2-x Zn x O 5+δ (SBSFZn x ) was prepared by electrospinning. (x = 0.1, 0.2, 0.3) nanofibers, which are used as the cathode materials for the prepared batteries. The XRD and Rietveld refinement results indicate that SBSFZn x presents a tetravalent structural system. With the introduction of Zn doping, the unit cell parameters increase and the lattice expands. Furthermore, the XPS results indicate that Fe presents a mixed valence state of Fe 3+ /Fe 4+ , among which SBSFZn 0.2 has the highest oxygen vacancy concentration. A solid oxide battery was composed of NiO + BZCY and SBSFZn x nanofibers as the cathode material, and its performance was tested. The test structure exhibits the maximum peak power density (PPD) of the device equals 712.12 mW cm -2 at 700 °C. So, Zn-doped SmBa 0.5 Sr 0.5 Fe 1.8 Zn 0.2 O 5+δ is a good choice for H-SOFC cathode materials.