3D Ion percolation path in gadolinium doped ceria nanofibres for solid oxide electrochemical cells

Understanding transport properties in ion conductive solids is key to supporting the development of devices for energy conversion, e.g., solid oxide electrochemical cells. Because of the complex nanostructured nature of such materials they have numerous types of grain boundaries and the prediction of the percolation path becomes challenging. We employ, for the first time, a combination of 3D orientation mapping in the transmission electron microscope and energy filtered transmission electron microscopy to map crystal orientation and doping concentration with nm-precision to predict 3D ion percolation paths in state-of-the-art electrospun (Ce_0.9Gd_0.1O_1.95) nanofibres. The results show that the conductivity of CGO nanofibres are affected by grain- and diameter size. Furthermore, we show that 3D-OMiTEM is a powerful non-destructive tool for determining 3D ion percolation paths with nm-precision of complex nanostructures.