Engineered Interfusion of Hollow Nitrogen‐Doped Carbon Nanospheres for Improving Electrochemical Behavior and Energy Density of Lithium–Sulfur Batteries

Abstract

Abstract Hollow nanostructures are one of promising sulfur host materials for lithium–sulfur (Li–S) batteries, but the ineffective contact among discrete particles usually generates overall poor electrical conductivity and low volumetric energy density. A new interfused hollow nitrogen‐doped carbon (HNPC) material, derived from imidazolium‐based ionic polymer (ImIP)‐encapsulated zeolitic imidazolate framework‐8 (ZIF‐8), is reported. A novel method for ZIF‐8 disassembly induced by the decomposition of the ImIP shell is proposed. The unique structural superiority gives the resultant electrodes remarkable cycling stability, high rate capability, and large volumetric energy density. A stable reversible discharge capacity over 562 mA h g −1 at 2 C is achieved after prolonged cycling for 800 cycles and the average capacity decay per cycle is as low as 0.035%. The electrochemical performance achieved greatly surpasses that of ZIF‐8‐derived carbon matrices and conventional nitrogen‐doped carbon materials. This proposed methodology opens a new avenue for the design of hollow‐structured carbon nanoarchitectures with target functionalities.