알루미늄 도핑된 스피넬 구조에서의 얀-텔러 효과의 이해

Through first-principles calculations and experimental observations, we present the fundamental understanding of mechanism of the suppression of Jahn-Teller effects using Al doping in the cubic spinel oxide (LiMn2O4). The Al-doped spinel exhibits better cycle stability as compared with the pristine spinel. Considering partial density of states (PDOS) and band fillings of the two oxides from the first-principles calculations, the pristine spinel is entirely suffered from Jahn-Teller distortion by Mn3+, indicating the anisotropic electronic structure. On the other hand, the Al-doped spinel shows suppressed Jahn-Teller effects, presenting the isotropic electronic structure. These findings based on the mechanistic understanding of Jahn-Teller effects are expected to be a basic solution and design new cathodes for the electrochemically enhanced properties in Li-ion batteries.