串联纳米反应器链式结构设计助力高性能 锂硫电池

The Design of a Chain Structure for the Series-Connected Nano-Reactor Helps to Achieve High-Performance Lithium-Sulfur Batteries

摘要: 锂硫电池因高理论能量密度和低成本优势被认为是下一代高比能储能体系的重要候选者，但多硫化锂穿梭、缓慢反应动力学和电极结构失稳仍限制其实际应用。本文提出一种链式串联结构正极材料(CNF/ZIS-IO-NR)，通过静电纺丝将ZnIn₂S₄修饰的In₂O₃圆柱状纳米反应器有序连接于碳纳米纤维导电骨架中。该结构中，In₂O₃壳层提供稳定限域空间，ZnIn₂S₄纳米片促进多硫化锂氧化还原转化，连续碳纳米纤维网络降低纳米反应器间的界面传输阻抗。得益于“限域–催化–传输”协同作用，CNF/ZIS-IO-NR电极在0.1 C下实现652.75 mAh g⁻¹的初始放电比容量，在1 C下保持424.78 mAh g⁻¹，并稳定循环1000次，单圈容量衰减率仅为0.042%。该研究为通过链式串联纳米反应器提升硫正极反应效率提供了新思路。

Abstract: Lithium-sulfur batteries are regarded as an important candidate for the next-generation high-energy-density energy storage system due to their high theoretical energy density and low cost. However, issues such as lithium polysulfide shuttle, slow reaction kinetics, and unstable electrode structure still limit their practical application. This study proposes a chain-serial structure cathode material (CNF/ZIS-IO-NR), which connects ZnIn₂S₄-modified In₂O₃ cylindrical nanoreactors orderly onto the carbon nanofiber conductive framework through electrospinning. In this structure, the In₂O₃ shell layer provides a stable confined space, the ZnIn₂S₄ nanosheets promote the redox conversion of lithium polysulfide, and the continuous carbon nanofiber network reduces the interface transmission impedance between the nanoreactors. Thanks to the “confined-catalytic-transmission” synergy, the CNF/ZIS-IO-NR electrode achieves an initial discharge specific capacity of 652.75 mAh g⁻¹ at 0.1 C, maintains 424.78 mAh g⁻¹ at 1 C, and undergoes stable cycling for 1000 times with a single-loop capacity degradation rate of only 0.042%. This research provides a new idea for enhancing the reaction efficiency of the sulfur cathode through chain-serial nanoreactor structures.