Soochow Institute for Energy and Materials InnovationS (SIEMIS), Key Laboratory of Advanced Carbon Materials and Wearable Energy Technologies of Jiangsu Province , Soochow University , Suzhou , Jiangsu 215006 , People's Republic of China.
Center for Multidimensional Carbon Materials (CMCM) , Institute for Basic Science (IBS) , Ulsan 689-798 , Republic of Korea.
ACS Appl Mater Interfaces. 2018 May 9;10(18):15733-15741. doi: 10.1021/acsami.8b02920. Epub 2018 Apr 30.
The lithium-sulfur (Li-S) battery has been deemed as one of the most promising energy-storage systems owing to its high energy density, low cost, and environmental benignancy. However, the capacity decay and kinetic sluggishness stemming from polysulfide shuttle effects have by far posed a great challenge to practical performance. We herein demonstrate the employment of low-cost, wet-chemistry-derived VO nanobelts as the effective host additives for the graphene-based sulfur cathode. The VO nanobelts displayed an ultrafast anchoring behavior of polysulfides, managing to completely decolor the polysulfide solution in 50 s. Such a fast and strong anchoring ability of VO was further investigated and verified by experimental and theoretical investigations. Benefitting from the synergistic effect exerted by VO in terms of chemical confinement and catalytic conversion of polysulfides, the Li-S batteries incorporating VO and graphene manifested excellent cycling and rate performances. Notably, the batteries delivered an initial discharge capacity of 1405 mAh g when cycling at 0.2 C, showed an advanced rate performance of ∼830 mAh g at 2 C, and maintained a stable cycling performance at high current densities of 1, 2, and 5 C over 200 cycles, paving a practical route toward cost-effective and environmentally benign cathode design for high-energy Li-S batteries.
锂硫（Li-S）电池因其高能量密度、低成本和环境友好性而被认为是最有前途的储能系统之一。然而，多硫化物穿梭效应引起的容量衰减和动力学迟缓迄今为止对实际性能构成了巨大挑战。本文展示了使用低成本的湿法化学衍生的 VO 纳米带作为基于石墨烯的硫阴极的有效主体添加剂。VO 纳米带对多硫化物表现出超快的锚定行为，能够在 50 s 内完全使多硫化物溶液褪色。通过实验和理论研究进一步研究和验证了 VO 的这种快速和强锚定能力。得益于 VO 在化学限制和多硫化物催化转化方面的协同作用，包含 VO 和石墨烯的 Li-S 电池表现出优异的循环和倍率性能。值得注意的是，电池在 0.2 C 循环时的初始放电容量为 1405 mAh g-1，在 2 C 时具有先进的倍率性能，约为 830 mAh g-1，在 1、2 和 5 C 的高电流密度下稳定循环 200 次以上，为高能 Li-S 电池的高性价比和环境友好型阴极设计铺平了道路。
