Electrochemical properties of micro-tubular intermediate temperature solid oxide fuel cell with novel asymmetric structure based on BaZr0.1Ce0.7Y0.1Yb0.1O3−δ proton conducting electrolyte

Abstract This study employed a simple phase-inversion method to achieve anode-supported micro-tubular solid oxide fuel cells on the basis of the BaZr0.1Ce0.7Y0.1Yb0.1O3−δ proton conducting electrolyte. The typical cell with configuration of Ni–BaZr0.1Ce0.7Y0.1Yb0.1O3−δ|BaZr0.1Ce0.7Y0.1Yb0.1O3−δ|La0.6Sr0.4Co0.2Fe0.8O3-δ-Sm0.2Ce0.8O2-δ. The novel “sponge-like micro-pores electrode | homogeneous porous functional layer” asymmetric pore structure is obtained. Achieved results include: i) the electrodes revealed the single phase collected by the powder X-Ray Diffractometer analysis; ii) observed by Scanning Electron Microscope, the single cell presenting uniform distribution of micro sponge-like pores electrode was well-adhered to the dense and crack-free 12 μm thick electrolyte layer; iii) the cells showed excellent electrochemical performance with the maximum power densities of 1.070, 0.976, 0.815, and 0.700 W cm−2 at 750, 700, 650 and 600 °C, respectively, characterized by Electrochemical Impedance Spectroscopy; iv) the designed cell clearly indicated a very low concentration polarization value (0.01 and 0.02 Ω cm2 at 750 and 700 °C). Our findings provide a promising approach to improve intermediate temperature solid oxide fuel cells performance by optimizing the electrode-electrolyte interface microstructure, based on proton and oxide ion mixed conductor electrolytes.