The origin of heavy element doping to relieve the lattice thermal vibration of layered materials for high energy density Li ion cathodes

We report an effective strategy to inhibit the phase transition of LiCoO2 from hexagonal layered to cubic spinel during delithiation. The small thermal vibration amplitude of the Sn dopant helps pin the lattice vibration, stabilizing CoO6 octahedra during charge/discharge.

The Effects of Sn-Doping on a-Fe2O3 Nanostructures Properties

In this study, undoped and Sn-doped hematite (α-Fe2O3) nanostructures with variation of Sn (0.5, 1, 2, 3 at. %) were deposited on fluorine doped tin oxide (FTO) coated glass substrate using sonicated immersion method. The effect of Sn-dopant on structural and crystallinity properties were investigated by characterizing FESEM and XRD respectively, while the optical properties were measured by UV-Vis-NIR spectrometer. The surface morphologies from FESEM have shown that the hematite nanostructures were grown uniformly in all samples. However, as the dopant atomic percentage increases, the amount of hematite nanostructure being grown on the FTO decreases. Results demonstrated that the amount of Sn-doping was undoubtedly influence the structural, optical and electrical properties of hematite nanostructures.