Monolayer 1 T-Phase TaSe 2 for High-Performance Li + and Na + storage

Developing novel and high-performance anode materials as lithium-ion (Li + ) and sodium-ion (Na + ) hosts is urgent. Herein, a novel conductive two-dimensional (2D) 1 T-phase TaSe 2 (1 T-TaSe 2 ) is proposed firstly as a promising anode material for Li + and Na + storage based on density functional theory (DFT). The 2D 1 T-TaSe 2 is stable at room temperature thermodynamically. The anode material shows high specific capacities of 640 and 480 mAh g −1 for Li + and Na + storage, respectively. Moreover, the energy barrier of Li + and Na + diffusion over the 2D 1 T-TaSe 2 is as low as 0.052 eV and 0.015 eV respectively, suggesting its excellent rate performance. The plateau of open current voltage for Li + and Na + storage is ~ 0.45 V and ~ 0.35 V respectively, ensuring safety and high energy density simultaneously. The possibility of experimental preparation by the top-down approach is also estimated based on its anisotropic mechanical properties. The 2D 1 T-TaSe 2 is a potential high-performance anode material. Graphical Abstract