High strength bilayer finger-like ceramic supported reversible solid oxide cells via phase inversion tape-casting technology

Reversible solid oxide fuel cells (RSOCs) are advanced energy conversion and storage devices, allowing for the flexible interconversion of electricity and chemical energy in fuels like hydrogen or syngas. However, the pores structure of RSOCs prepared by conventional methods is not conducive to fuel gas diffusion, resulting in severe concentration polarization. In this work, a novel cell structure with 3 mol% Y2O3 stabilized ZrO2 (3YSZ) | NiO-Sc2O3 stabilized ZrO2 (SSZ) bilayer finger-like porous structure with favorable strength is successfully prepared by the phase-inversion tape casting method. The peak power density of the cell is reached 0.97 W cm(-2) at 800 degrees C in the fuel cell (FC) mode and no notable degradation is observed after undergoing 30 thermal cycles at 0.75 V. Furthermore, the cell demonstrates a current density of 1.00 A cm(-2) when operated in electrolysis cell (EC) mode with 90% H2O at 800 degrees C and 1.3 V, and no obvious degradation is observed on the cell alternating between FC mode and EC mode alternately for 80 h. These results show the improvement of mechanical strength and mass transfer, and strengthen the application ability of 3YSZ | NiO-SSZ bilayer finger-like porous structure in RSOCs.