Ti–Cl bonds decorated Ti2NTx MXene towards high-performance lithium-ion batteries. (1st January 2023)

• Record Type: Journal Article
• Authors: Cao, Yuyang; Wei, Shiqiang; Zhou, Quan; Zhang, Pengjun; Wang, Changda; Zhu, Kefu; Xu, Wenjie; Guo, Xin; Yang, Xiya; Wang, Yixiu; Wu, Xiaojun; Chen, Shuangming; Song, Li
• Is Part Of: 2D materials. Volume 10:Number 1(2023)
• Publication Date: 2023-01-01
• Subjects: chlorine termination -- nitride MXene -- lithium-ion battery (LIB) -- XAFS; Graphene -- Periodicals; Materials science -- Periodicals; Nanostructured materials -- Periodicals; 620.115
• DOI: 10.1088/2053-1583/ac953b
• Languages: English
• ISSNs: 2053-1583

Abstract

Abstract: Transition metal carbides or nitrides, collectively known as MXenes, are burgeoning two-dimensional materials for energy conversion and storage. The surface chemistry of MXenes could be specially tuned by the modified surface terminations, which directly influences their physicochemical properties. However, the in-depth study and understanding of the specific microstructure and the influence on the electrochemical performance of these terminations remain lacking. Herein, we present an accordion layered Ti2 NT x MXene with –Cl and –O terminations obtained from copper chloride molten salt etching at a relatively low temperature. X-ray absorption fine structure and x-ray photoelectron spectroscopy analyses reveal the formation of Ti–Cl and Ti–O bonds on the surface of Ti2 NT x MXene. Density functional theory calculations further suggest that the surface terminations tend to be replaced by –O terminations after Ti–Cl decoration, which implies promising lithium-ion storage performance due to the high lithium affinity of –O terminations. As a result, the Ti2 NT x MXene based electrode delivers a high reversible capacity (303.4 mAh g −1 at 100 mA g −1 ), stable cycling capability (1200 cycles without capacity attenuation), and fast Li + storage (52% capacity retention at 32 C). This work provides a new vision for MXene surface chemistry and an effective avenue to prepare high-performance nitride electrodes, expanding the diversity and controllability of the MXenes family.