Li Narui, Yu Lihong, Xi Jingyu
Institute of Materials Research, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen, 518055, China.
School of Applied Chemistry and Biological Technology, Shenzhen Polytechnic, Shenzhen, 518055, China.
Small. 2021 Sep;17(37):e2103001. doi: 10.1002/smll.202103001. Epub 2021 Jul 31.
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 TiO -TiN heteronanowires (CCC@TiO -TiN) is proposed to replace the traditional cathode. Concretely, one side of CCC@TiO -TiN serves as a current-collector to load sulfur (CCC@TiO -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 TiO -TiN heteronanowires work as in situ capture and catalysis sites for the reversible and accelerated sulfur redox reaction. Therefore, the intergrated cathode of CCC@TiO -TiN/S achieves an ultrahigh sulfur loading of 13 mg cm and delivers a superb areal capacity of 9.09 mAh cm under the ultralow E/S ratio of 4.6 µL mg . This work provides a new model material to achieve high sulfur loading and lean-electrolyte toward the practical LSBs with high specific energy density.
低硫负载量、高电解质/硫(E/S)比以及缓慢的硫氧化还原反应是严重阻碍锂硫电池(LSBs)实际应用的主要挑战。为了解决这些问题,提出了一种用TiO -TiN异质纳米线装饰的自立式中空碳化棉布(CCC)来替代传统阴极。具体而言,CCC@TiO -TiN的一侧用作集流体来负载硫(CCC@TiO -TiN/S),而另一侧面对隔膜则作为中间层以抑制穿梭效应。这种先进的集成中间层/集流体阴极具有出色的三维电子/离子传输能力、强大的限制屏障和大量的硫负载位点。此外,所制备的TiO -TiN异质纳米线作为可逆且加速硫氧化还原反应的原位捕获和催化位点。因此,CCC@TiO -TiN/S的集成阴极在4.6 µL mg的超低E/S比下实现了13 mg cm的超高硫负载量,并提供了9.09 mAh cm的超高面积容量。这项工作为实现高硫负载和贫电解质的高比能量密度实用LSBs提供了一种新型模型材料。