Synthesis, Crystal Structure, and Electrochemical Properties of (Li,Na)xMn1−yTiyO2 (0 < y < 0.49) with O3-type Layered Structure

Abstract

Abstract O3-type (Li,Na)xMn1−yTiyO2 (0 < y < 0.49) materials were first prepared from Na0.7Mn1−yTiyO2 via Na/Li ion exchange. The substitution of Ti for Mn was confirmed by using XRD and STEM-EDX mapping. The solubility limit of Ti for Mn was estimated to be less than 0.49. The electrochemical measurements between 4.5 and 2.4 V showed that the initial discharge capacity increased from 163 to 191 mA h g−1 with decreasing Ti contents, while the capacity retention rate increased with Ti contents.