Ti-doped SrFeO3 nanostructured electrodes for symmetric solid oxide fuel cells

Abstract

Nanostructured electrodes of Sr_0.98Fe_1−xTi_xO_3−δ are evaluated as both cathode and anode for solid oxide fuel cells. The electrodes are prepared by a low-cost and simple procedure based on spray-pyrolysis deposition on a porous Ce_0.8Gd_0.2O_1.9 (CGO) layer. A homogenous coating layer of electrode catalyst nanoparticles is formed on the CGO backbone surface in a single deposition-firing step. Sr_0.98Fe_0.8Ti_0.2O_3−δ (SFT_0.2) exhibits high efficiency operating as both cathode and anode with polarization resistance values of 0.1 Ω cm² in air and 0.07 Ω cm² in humidified H₂ at 700 °C. An electrolyte supported cell with 300 μm thick La_0.9Sr_0.1Ga_0.8Mg_0.2O_3−δ electrolyte and SFT_0.2 symmetric electrodes shows maximum power densities of 700 and 140 mW cm⁻² at 800 and 600 °C, respectively.