,First-principles study of high performance lithium/sodium storage of Ti3C2T2 nanosheets as electrod

• 作 者: Li-Na Bai Ling-Ying Kong Jing Wen Ning Ma Hong Gao Xi-Tian Zhang
• 机 构: Key Laboratory for Photonic and Electronic Bandgap Materials, Ministry of Education, School of Physi
• 出 处: 中国物理B（英文版）
• 发表日期: 2020年1期
• 关键词: density functional theory MXene electrode materials

Ti3C2Tx nanosheet, the first synthesized MXene with high capacity performance and charge/discharge rate, has at-tracted increasingly attention in renewable energy storage applications. By performing systematic density functional theory calculations, the theoretical capacity of the intrinsic structure of single-and multi-layered Ti3C2T2 (T=F or O) correspond-ing to M (M=Li and Na) atoms are investigated. Theoretical volumetric capacity and gravimetric capacity are obtained, which are related to the stacking degree. The optimal ratios of capacity to structure are determined under different stacking degrees for understanding the infl uence of surface functional groups on energy storage performance. Its performance can be tuned by performing surface modification and increasing the interlayer distance. In addition, the reason for theoreti-cal capacity differences of M atoms is analyzed, which is attributed to difference in interaction between the M-ions and substrate and the difference in electrostatic exclusion between adsorbed M-ions. These results provide an insight into the understanding of the method of efficiently increasing the energy storage performance, which will be useful for designing and using high performance electrode materials.