Regulating interlayer spacing with pillar and strain structures in Ti3C2 MXene layers by molecular welding for superior alkali metal ion storage. (December 2021)

• Record Type: Journal Article
• Authors: Liu, Mao-Cheng; Zhang, Bin-Mei; Zhang, Yu-Shan; Gu, Bing-Ni; Tian, Chen-Yang; Zhang, Dong-Ting; Wang, Ya-Qin; Zhao, Bei; Wang, Yuan-Yi; Liu, Ming-Jin; Yu, Yi-Jen; Zhao, Kun; Kong, Ling-Bin; Chueh, Yu-Lun
• Is Part Of: Materials today energy. Volume 22(2021)
• Publication Date: 2021-12
• Subjects: Two-dimensional materials -- Organic molecular welding -- Tunable interlayer spacing -- Fast Li+/Na+ diffusion dynamics -- High-rate capability; Energy development -- Periodicals; Energy industries -- Periodicals; Power resources -- Periodicals; Energy policy -- Periodicals; Energy development; Energy industries; Energy policy; Power resources; Electronic journals; Periodicals; 621.042
• DOI: 10.1016/j.mtener.2021.100832
• Languages: English
• ISSNs: 2468-6069

Abstract

Abstract: An ion insertion type in two-dimensional (2D) materials has attracted extensive attention making 2D materials as promising energy storage materials. However, the interlayer spacing plays a key role in the design of 2D materials with fast ions de-intercalation dynamics and high-rate capability. Here, an unprecedented and convenient organic molecular welding approach was proposed to controllably tune different interlayer spacings in Ti3 C2 MXene layers, resulting in pillar and strain- x DA-Ti3 C2 structures by a dehydration condensation reaction between diacid molecules (HOOC(CH2 ) n COOH) and -NH2 functionalized Ti3 C2 layers. The x DA molecules can not only tighten the adjacent layers acting as ropes during the ion insertion process but also pillar the adjacent layers when ion extraction process was used to stabilize the Ti3 C2 structure by suppressing the volume change. Furthermore, the interlayer spacing of x DA-Ti3 C2 can be controllably tuned from 1.03 to 1.45 nm by choosing x DA with different lengths and controlled interlayer spacings of 1.35 and 1.38 nm can be achieved for the best rate capability of insertion/extraction processes with the superior diffusion coefficient of 4.6 × 10 −7 /2.8 × 10 −8 cm 2 /s in Li + /Na + batteries, respectively. Graphical abstract: Image 1 Highlights: Organic molecular welding between diacid molecules and -NH2 functionalized Ti3 C2 was demonstrated to prepare xDA-Ti3 C2 . The xDA-Ti3 C2 shows a unique pillar/strain 2D layered structure and controllably tuned interlayer spacing. The xDA-Ti3 C2 exhibits high rate alkali metal ion storage capability and long cycle stability. Organic molecular welding is a novel approach to controllably tune the interlayer spacing of other 2D materials.