Fast Energy Storage of SnS2 Anode Nanoconfined in Hollow Porous Carbon Nanofibers for Lithium-Ion Batteries

The development of conversion-typed anodes with ultrafast charging and large energy storage is quite challenging due to the sluggish ions/electrons transfer kinetics in bulk materials and fracture of the active materials. Herein, the design of porous carbon nanofibers/SnS2 composite (SnS2@N-HPCNFs) for high-rate energy storage, where the ultrathin SnS2 nanosheets are nanoconfined in N-doped carbon nanofibers with tunable void spaces, is reported. The highly interconnected carbon nanofibers in three-dimensional (3D) architecture provide a fast electron transfer pathway and alleviate the volume expansion of SnS2, while their hierarchical porous structure facilitates rapid ion diffusion. Specifically, the anode delivers a remarkable specific capacity of 1935.50 mAh g(-1) at 0.1 C and excellent rate capability up to 30 C with a specific capacity of 289.60 mAh g(-1). Meanwhile, at a high rate of 20 C, the electrode displays a high capacity retention of 84% after 3000 cycles and a long cycle life of 10 000 cycles. This work provides a deep insight into the construction of electrodes with high ionic/electronic conductivity for fast-charging energy storage devices.

Automated summary

This study reports a porous carbon nanofibers/SnS2 composite for high-rate energy storage, which exhibits a highly interconnected carbon nanofibers structure and a hierarchical porous structure, resulting in fast electron transfer and rapid ion diffusion. The composite shows excellent energy storage performance and long cycle life.