Ab Initio Prediction and Characterization of TiB<sub>2</sub> as a Two-Dimensional Dirac Anode for Metal (Li/Na/Mg) Ion Batteries
Yuling Zhao, Diancheng Chen, Yichun Zheng, Yang Sun
Abstract
Two-dimensional (2D) Dirac materials exhibit promising characteristics as anode materials due to their exceptional conductivity and versatile properties. This study explores the potential of TiB 2 monolayers as a 2D Dirac anode for both lithium-ion batteries (LIBs) and nonlithium-ion batteries (NLIBs) using density functional theory. Our findings demonstrate that TiB 2 monolayers possess outstanding mechanical, dynamic, and thermal stability. The calculated adsorption energy values suggest that the adsorption of Li, Na, and Mg atoms on the TiB 2 monolayer is a favorable process. Additionally, the TiB 2 monolayer maintains its metallic nature and undergoes minimal volume expansion (<2%) during Li/Na/Mg intercalation, ensuring excellent conductivity and long-term cycle stability. The ultralow barrier energy for Li, Na, and Mg (0.04, 0.06, and 0.07 eV, respectively) along with a suitable open-circuit voltage indicates exceptional charging and discharging capabilities. Moreover, the high specific storage capacities of 771, 771, and 3084 mA h g –1 for Li, Na, and Mg, respectively, surpass those of traditional anode materials like graphite. Ab initio molecular dynamics simulations reveal that the TiB 2 monolayer is stable at room temperature. This research offers valuable insights for the development of advanced rechargeable metal-ion batteries with high capacity and a lightweight design.