Integrated Design of Interlayer/Current-Collector: Heteronanowires Decorated Carbon Microtube Fabric for High-Loading and Lean-Electrolyte Lithium-Sulfur Batteries

Low sulfur loading, high electrolyte/sulfur (E/S) ratio, and sluggish sulfur redox reaction are the main challenges that severely impede the practical application of lithium-sulfur batteries (LSBs). To address these problems, a self-standing hollow carbonized cotton cloth (CCC) decorated with TiO2-TiN heteronanowires (CCC@TiO2-TiN) is proposed to replace the traditional cathode. Concretely, one side of CCC@TiO2-TiN serves as a current-collector to load sulfur (CCC@TiO2-TiN/S), while the other side facing the separator acts as interlayer to inhibit shuttle effect. This advanced intergrated interlayer/current-collector cathode is endowed with excellent 3D electron/ion transportation, a strong confinement barrier, and vast sulfur loading sites. Moreover, the as-developed TiO2-TiN heteronanowires work as in situ capture and catalysis sites for the reversible and accelerated sulfur redox reaction. Therefore, the intergrated cathode of CCC@TiO2-TiN/S achieves an ultrahigh sulfur loading of 13 mg cm(-2) and delivers a superb areal capacity of 9.09 mAh cm(-2) under the ultralow E/S ratio of 4.6 mu L mg(-1). This work provides a new model material to achieve high sulfur loading and lean-electrolyte toward the practical LSBs with high specific energy density.

Automated summary

This study proposes a new energy storage material that addresses the challenges of low sulfur loading, high E/S ratio, and slow sulfur redox reactions in lithium-sulfur batteries. By using a self-standing hollow carbonized cotton cloth decorated with TiO2-TiN heteronanowires, an integrated interlayer/current-collector cathode with excellent performance is achieved, enabling high sulfur loading and charging capacity.