Supersized Graphitic Tube@MoS2 Pipelines with Abundant Ion Channels Synthesized by Selective Deposition toward High-Performance Anodes

Abstract

Molybdenum disulfide (MoS2) has been regarded as a promising anode material in lithium-ion batteries (LIBs) due to its high theoretical capacity. However, the poor conductivity and collapse of the structure upon cycling lead to poor stability, impeding the application of MoS2 in LIBs. Here, a novel strategy was reported to selectively deposit MoS2 nanosheets on a supersized graphitic tube (SGT) to obtain an SGT@MoS2 pipeline to tackle these problems. Compared with a conventional carbon nanotube (CNT), SGT has not only a graphitic wall but also a pipeline structure, which can act as an ion channel after immersion of an electrolyte. Additionally, the selective deposition of MoS2 on the outer surface effectively prevents the pipelines from being crammed by MoS2 nanosheets. Resultantly, diffusion efficiencies of both an electron and an ion are enhanced. Additionally, the shortened ion diffusion distance can boost pseudocapacitive behavior, contributing to high specific capacity and excellent rate performance. The results manifest that the specific capacity of the SGT@MoS2 pipeline reached 942 mAh g–1 at 100 mA g–1 after 200 cycles, 4 times higher than that of pure MoS2.