摘要
Lithium sulfur(Li-S)batteries have been regarded as a promising next-generation energy storage system with high theoretical specific capacity and energy density,but still facing challenges.In order to make Li-S batteries more competitive,combination of trapping sites and electrocatalytic properties for polysulfides is an effective way to improve the battery performance.In this study,we prepare a type of multifunctional V3S4-nanowire/graphene composites(V3S4-G)by uniformly dispersing V3S4 nanowires on the graphene substrate.This structure contributes to the sufficient exposure of multifunctional V3S4 active sites which can anchor polysulfides and accelerate reaction kinetics.Thus,the Li-S batteries based on the multifunctional V3S4-G sulfur cathode deliver a stable cycling performance and good rate capability.Even at sulfur loading of 3 mg cm^−2,the V3S4-G sulfur cathode possesses a low capacity decay rate of 0.186%per cycle at 0.5 C.
具有高理论比容量与能量密度的锂硫电池被认为是一种颇具前景的新一代能量储存系统,但其目前仍面临一定挑战.将多硫化物的吸附位点与电催化性能相结合,是提升电池性能的有效方法.在本工作中,我们将一种V3S4纳米线均匀分布在石墨烯基底上得到了多功能V3S4纳米线/石墨烯复合材料(V3S4-G).该材料的结构,有助于暴露V3S4活性中心,从而锚定多硫化锂并提升其反应动力学.基于该多功能V3S4-G硫正极的锂硫电池表现出稳定的循环性能与良好的倍率性能.即使在硫的负载量达到3 mg cm^−2时,在0.5 C的电流密度下,该V3S4-G硫正极仍然保持低的容量衰减速率(每圈0.186%).
作者
Tianyu Tang
Teng Zhang
Lina Zhao
Biao Zhang
Wei Li
Junjie Xu
Tao Li
Long Zhang
Hailong Qiu
Yanglong Hou
唐天宇;张腾;赵丽娜;张彪;李巍;徐俊杰;李涛;张隆;邱海龙;侯仰龙(Beijing Key Laboratory for Magnetoelectric Materials and Devices(BKLMMD),Beijing Innovation Center for Engineering Science and Advanced Technology(BIC-ESAT),Department of Materials Science and Engineering,College of Engineering,Peking University,Beijing 100871,China;Clean Nano Energy Center,State Key Laboratory of Metastable Materials Science and Technology,College of Materials Science and Engineering,Yanshan University,Qinhuangdao 066004,China)
基金
We acknowledge the financial support from the National Key R&D Program of China(2016YFA0200102 and 2017YFA0206301)
the National Natural Science Foundation of China(51631001,51590882,51672010 and 81421004).
