Nanostructured MoS<sub>2</sub> with Interlayer Controllably Regulated by Ionic Liquids/Cellulose for High‐Capacity and Durable Sodium Storage Properties
Wenjie Tao, Jianqiang Chen, Chengjie Xu, Shuai Liu, Sandile Fakudze, Jie Wang, Chen Wang
Abstract
Abstract Low intrinsic conductivity and structural instability of MoS 2 as an anode of sodium‐ion batteries limit the liberation of its theoretical capacity. Herein, density functional theory simulations for the first time optimize MoS 2 interlayer distance between 0.80 and 1.01 nm for sodium storage. 1‐Butyl‐3‐methyl‐imidazolium acetate ([BMIm]Ac) induces cellulose oligomers to intercalate MoS 2 interlayers for achieving controllable distance by changing the mass ratio of cellulose to [BMIm]Ac. Based on these findings, porous carbon loading the interlayer‐expanded MoS 2 allowing Na + to insert with fast kinetics is synthesized. A carbon layer derived from [BMIm]Ac and cellulose coating the composite prevents the MoS 2 from contacting electrolytes, leading to less sulfur loss for a more reversible specific capacity. Meanwhile, MoS 2 and carbon have a strong interfacial connection through MoN binding, contributing to enhanced structural stability. As expected, while cycling 250 times at 0.1 A g ‐1 , the MoS 2 ‐porous carbon composite displays an optimal reversible capacity at 517.79 mAh g ‐1 as a sodium‐ion batteries anode. The cyclic test of 1.0 A g ‐1 also shows considerable stability (310.74 mAh g ‐1 after 1000 cycles with 86.26% retentive capacity). This study will open up new possibilities of modifying MoS 2 that serves as an applicable material as sodium‐ion battery anode.