Multiple Length Scale Characterization of Doped Lanthanum Manganate Composite Cathodes

Composite cathodes extend the electrochemically active region for solid oxide fuel cells (SOFCs). The complex microstructural and chemical composition of composite cathodes often make them difficult to fully characterize. The active regions of composite cathodes were analyzed at various length scales using Focused Ion Beam/Scanning Electron Microscope (FIB/SEM) and Transmission Electron Microscope (TEM) techniques, to verify the effect of calcium doping on microstructure and interfacial stability. Dual beam FIB/SEM three-dimensional (3-D) reconstructions provided micron-level information on porosity, surface area and tortuosity while the TEM provided nanometer-level two-dimensional (2-D) chemical characterization of the interface between the cathode and electrolyte. These characterization techniques were applied on two different calcium doped lanthanum manganite (LCM)-scandium stabilized zirconia (SCZ) composite cathodes.