Nanofiber Sr₂Fe_1.5Mo_0.5O_6-δ Electrodes Fabricated by the Electrospinning Method for Solid-Oxide Cells

Abstract

Solid oxide cells (SOCs) are attracting much more attention as promising energy conversion and storage devices. One of the challenges of optimizing of solid-oxide cells’ performance is that there are not enough triple-phase boundaries (TPB) in the electrode bulk. To enhance the reaction area for SOCs, Sr2Fe1.5Mo0.5O6-δ nanofibers are synthesized by electrospinning with metal nitrate precursors and used for SOC electrodes operated in both humidified air and a hydrogen atmosphere. SFMO nanofibers display a highly porous and crystallized perovskite structure and continuous pathways by XRD analysis and SEM observation. The average diameter of the SFMO nanofibers after sintering is about 100 nm. The La0.8Sr0.2Ga0.8Mg0.2O3-δ(LSGM) electrolyte-supported symmetrical cell with the SFMO nanofiber electrode exhibits enhanced electrochemical performance in humidified air and an H2 atmosphere. Moreover, a distribution of the relaxation time method is used to analyze the impedance spectra, and the polarization peaks observed are assigned to correspond different electrochemical processes. The results indicate that the SFMO nanofiber with an improved nanostructure can be the potential material for the SOC electrode.

Keywords

• solid-oxide cells
• electrospinning nanofiber
• distribution of relaxation time