Comparison of SOFC cathode microstructure quantified using X-ray nanotomography and focused ion beam–scanning electron microscopy

X-ray nanotomography and focused ion beam scanning electron microscopy (FIB‐SEM) have been applied to investigate the complex 3D microstructure of solid oxide fuel cell (SOFC) electrodes at spatial resolutions of 45 nm and below. The application of near edge differential absorption for x-ray nanotomography and energy selected backscatter detection for FIB–SEM enable elemental mapping within the microstructure. Using these methods, non‐destructive 3D x-ray imaging and FIB–SEM serial sectioning have been applied to compare three‐dimensional elemental mapping of the LSM, YSZ, and pore phases in the SOFC cathode microstructure. The microstructural characterization of an SOFC cathode is reported based on these measurements. The results presented demonstrate the viability of x-ray nanotomography as a quantitative characterization technique and provide key insights into the SOFC cathode microstructure.

Research Highlights
► Solid oxide fuel cell cathode microstructure is characterized with x-ray nanotomography and FIB-SEM.
► Near edge differential absorption and EsB detection enable elemental mapping of distinct cathode phases (e.g. LSM, YSZ, pore).
► The accuracy of cathode characterization by x-ray nanotomography is confirmed.