Ab initio study of the surface properties and nanoscale effects of LiMnPO4

Using first-principles calculations, we investigate the surface energies, equilibrium morphology, and surface redox potentials for LiMnPO4 in the olivine structure. Low-energy surfaces are found in the [100], [010], [011], [101], [201], and [301] directions of the orthorhombic structure. With the calculated surface energies, we provide the thermodynamic equilibrium shape for the LiMnPO4 crystal through a Wulff construction. The dominating surfaces in the Wulff shape are (010), (011), and (201). Most of the surfaces in the Wulff shape have lower Li extraction potentials than the bulk, except for the (100) and (011) surfaces.