摘要
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 Ti 3 C 2 MXene layers, resulting in pillar and strain-xDA-Ti 3 C 2 structures by a dehydration condensation reaction between diacid molecules (HOOC(CH 2 ) n COOH) and -NH 2 functionalized Ti 3 C 2 layers. The xDA 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 Ti 3 C 2 structure by suppressing the volume change. Furthermore, the interlayer spacing of xDA-Ti 3 C 2 can be controllably tuned from 1.03 to 1.45 nm by choosing xDA 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.