Microstructural evolution during β
-phase deposition and stripping through the open-porous MIEC interlayer. (a) Schematic representation of the movement of different metallic elements during charging and discharging processes. (b) Cross-sectional TEM, corresponding EDS images, and the selected area diffraction patterns of Ag nanoparticles in the MIEC interlayer at four different stages: pristine, after 0.1C charging, after 1 cycle, and after 100 cycles. (c) Cross-sectional SEM and corresponding EDS images for the MIEC interlayer at three different stages: pristine, after 0.1C charging, and after 0.1C discharging. Adapted from Ref. [25
] with permission from Springer Nature.