Preparation of a truncated octahedron LiNi0.5Mn1.5O4 by a solid-state method with high electrochemical performance

Abstract

A truncated octahedron structure LiNi0.5Mn1.5O4 is prepared by solid-state method. The result of X-ray diffraction (XRD) indexed to the truncated octahedron structure of LiNi0.5Mn1.5O4 with a cube space group of Fd3m. The results of scanning electron microscope (SEM) tests shows that the sample has a truncated octahedron structure with high crystallinity. Electrochemical tests display that the LiNi0.5Mn1.5O4 sample exhibits great electrochemical performance with a high reversible discharge capacity of 126.1 mAh g-1 at 0.5 C and excellent capacity retention of 92.8 % after 200 cycles. The superior performance of the synthesized sample is attributed to its appropriate proportions of {111} and {100} surfaces. It can achieve both high discharge capacity and good cyclic performance simultaneously.