Donor−π–Acceptor Heterosystem-Functionalized Porous Hollow Carbon Microsphere for High-Performance Li–S Cathode Materials with S up to 93 wt %
Donor−π–Acceptor Heterosystem-Functionalized Porous Hollow Carbon Microsphere for High-Performance Li–S Cathode Materials with S up to 93 wt %
复制标题
供体-受体%20异质系统功能化%20多孔%20中空%20碳%20微球%20for%20高性能%20Li-S%20阴极%20材料%20with%20S%20up%20to%2093%20wt%20
DOI：
10.1021/acsami.1c15133
复制
发表时间：
2021
期刊：
影响因子：
--
通讯作者：
Xuefeng Qian
中科院分区：
文献类型：
--
作者：
Changyu Yan;Wenqian Li;Liu Xuejiao;Ming Chen;Xi Liu;Li Xiaomin;Jiantao Zai;Xuefeng Qian
锂硫（Li-S）电池作为一种很有发展前途的储能系统，目前仍存在许多问题，特别是正极中硫含量低，影响了其应用。本文中，具有高达93wt%的S的阴极材料经由中空给体-π-受体异质体系设计，其将催化位点、吸附位点和良好的导电性结合在一起。在此指导下，制备了具有CoO颗粒和单个V原子装饰在其上的中空多孔碳球（Co/V-HPCS），为硫提供了足够的体积空间。即使由硫负载的Co/V-HPCS（Co/V-HPCS@S）制成的电极也具有90wt%的高含量（电极中的硫含量为约83.5wt%），并且阴极在0.2C下在100次循环后表现出575.2mAh g-1的优异放电容量。通过高分辨透射电子显微镜（HRTEM）的仔细分析，证实了负载在碳壳上的CoO颗粒和单个V原子的催化量，这赋予该材料优异的催化硫转移能力和优异的多硫化物吸附。这种阴极材料的概念增加了具有高振实密度和高能量密度的先进长寿命Li-S电池的可能性。
Lithium-sulfur (Li-S) batteries, as a prospective energy storage system, are still plagued by many problems that prevent them from their application, especially the low content of sulfur in the cathode. Herein, a cathode material with S up to 93 wt % is designed via a hollow donor-π-acceptor heterosystem, which combines catalytic sites, adsorption sites, and good conductivity together. Following this guidance, a hollow porous carbon sphere is prepared with CoO particles and single V atoms decorated on it (Co/V-HPCS), providing ultrahigh volumetric space for sulfur. Even the electrode made of sulfur-loaded Co/V-HPCS (Co/V-HPCS@S) has a high content of 90 wt % (sulfur content in the electrode is ∼83.5 wt %), and the cathode exhibits an excellent discharge capacity of 575.2 mAh g-1 under 0.2C after 100 cycles. With careful analysis by means of a high-resolution transmission electron microscope (HRTEM), the catalytic amounts of CoO particles and single V atoms loaded on the carbon shell are confirmed, which endows the material with outstanding catalytic ability to transfer sulfur and excellent adsorption of polysulfides. This concept of the cathode material increases the possibility of advanced long-life Li-S batteries with high tap density and high energy density.