Design of a p-Type Electrode for Enhancing Electronic Conduction in High-Mn, Li-Rich Oxides

• DOI: 10.1021/acs.chemmater.6b03032
• Publication Date: 2016-10-19T16:13:19Z
• Authors: Jin-Myoung Lim; Taesoon Hwang; Min-Sik Park; Maenghyo Cho; Kyeongjae Cho
• Keywords: 02 engineering and technology; 0210 nano-technology

We report the introduction of p-type conductivity in high-Mn, Li-rich oxides (HMLOs) by the introduction of Cu doping to improve intrinsic electronic conduction. The study is based on experimental observations and a fundamental understanding through first-principles electronic structure analysis. Although the Cu-doped HMLO (CuHMLO) has a crystal structure identical to the original HMLO, the electrochemical performance of CuHMLO is superior in terms of specific energy and power characteristics. Specifically, CuHMLO exhibits a larger specific capacity with enhanced rate capability, and could be charged at lower voltages and discharged at higher voltages. For the first-principles calculations, HMLO and CuHMLO structures are modeled based on Rietveld refinement of the powder X-ray diffraction data of the powders synthesized herein. The electronic structure of CuHMLO reveals the generation of an electron hole in the valence band, above the Fermi level, indicating p-type conductivity and improving the electroni...