Two-Dimensional BeB2 and MgB2 as High Capacity Dirac Anodes for Li-Ion Batteries: A DFT Study

• Published in: Journal of physical chemistry. C Vol. 126; no. 23; pp. 9642 - 9651
• Main Authors: Wan, Meiqian, Zhao, Shangquan, Zhang, Zhongyong, Zhou, Naigen
• Format: Journal Article
• Language: English
• Published: American Chemical Society 16-06-2022
• Subjects: C: Energy Conversion and Storage
• ISSN: 1932-7447; 1932-7455
• DOI: 10.1021/acs.jpcc.2c02563

The development of anode materials with good stability, high capacity, and excellent electrical conductivity is an important challenge for high-performance Li-ion batteries. Herein, the feasibility of BeB2 and MgB2 monolayers as Li-ion batteries anode materials has been theoretically investigated. The simulation results reveal that the BeB2 and MgB2 monolayers maintain good electrical conductivity throughout the lithiation process. Meanwhile, the Li–BeB2 and Li–MgB2 systems exhibit small changes in lattice (−1.66 and 1.75%) during the lithiation/delithiation process showing good cycle stability. The BeB2 and MgB2 monolayers exhibit high energy density for Li adsorption due to the high storage capacities (1749.8 and 1750.9 mAh g–1) and low average open-circuit voltage (0.333 and 0.697 V). The Li storage capacities of BeB2 and MgB2 are 4.5 times higher than that of the commercial anode material graphite. These results demonstrate that BeB2 and MgB2 monolayers can be used as promising alternative anode materials with high energy density for Li-ion batteries.