Porous-hollow nanorods constructed from alternate intercalation of carbon and MoS2 monolayers for lithium and sodium storage

Weak ion diffusion and electron transport due to limited interlayer spacing and poor electrical conductivity have been identified as critical roadbacks for fast and abundant energy storage of both MoS2-based lithium ion batteries (LIBs) and sodium ion batteries (SIBs). In this work, MoS2 porous-hollow nanorods (MoS2/m-C800) have been designed and synthesized via an annealing-followed chemistry-intercalated strategy to solve the two issues. They are uniformly assembled from ultrathin MoS2 nanosheets, deviated to the rod-axis direction, with expanded interlayer spacing due to alternate intercalation of N-doped carbon monolayers between the adjacent MoS2 monolayers. Electrochemical studies of the MoS2/m-C800 sample, as an anode of LIBs, demonstrate that the superstructure can deliver a reversible discharge capacity of 1,170 mAh center dot g(-1) after 100 cycles at 0.2 A center dot g(-1) and maintain a reversible capacity of 951 mAh center dot g(-1) at 1.25 A center dot g(-1) after 350 cycles. While for SIBs, the superstructure also delivers a reversible discharge capacity of 350 mAh center dot g(-1) at 0.5 A center dot g(-1) after 500 cycles and exhibits superior rate capacity of 238 mAh center dot g(-1) at 15 A center dot g(-1).The excellent electrochemical performance is closely related with the hierarchical superstructures, including expanded interlayer spacing, alternate intercalation of carbon monolayers and mesoporous feature, which effectively reduce ion diffusion barrier, shorten ion diffusion paths and improve electrical conductivity.