Optimization of a cobalt-free La0.7Sr0.3FeO3-δ-BaZr0.1Ce0.7Y0.2O3-δ composite cathode for proton-conducting solid oxide fuel cells

Abstract

Nano-sized hollow porous network composite cathode La0.7Sr0.3FeO3-δ-BaZr0.1Ce0.7Y0.2O3-δ (LSF-BZCY) is successfully prepared by electrostatic spinning and applied to anode-supported proton-conducting solid oxide fuel cell (H+-SOFC) with BaZr0.1Ce0.7Y0.2O3-δ (BZCY) as electrolyte. The pure phase of La0.7Sr0.3FeO3-δ (LSF) nanofiber is obtained after calcination at 700 oC for 2 h, and no impurity phases appear. The micrograph of LSF-BZCY composite cathode is characterized by loose texture and porous nanofiber structure. The electrochemical performance of H+-SOFC is excellent, with BZCY electrolyte and nanostructure cobalt-free composite cathode LSF-BZCY. At 700 oC, the peak power output corresponding to H+-SOFC is 849 mW cm-2, and the polarization impedance value is 0.12 Ω cm2. In this work, the efficiency of H+-SOFC is greatly improved at moderate temperatures by reshaping the microstructure of the LSF cathode. On this basis, more suitable cathode materials can be developed to promote the development of H+-SOFC.