Facile Synthesizing Yolk-Shelled Fe<sub>3</sub>O<sub>4</sub>@Carbon Nanocavities with Balanced Physiochemical Synergism as Efficient Hosts for High-Performance Lithium–Sulfur Batteries
Lai Chen,
Chenying Zhao,
Yun Lu,
Lingyi Wan,
Kang Yan,
Youxiang Bai,
Zhiyu Liu,
Xulai Yang,
Yuefeng Su,
Feng Wu
Affiliations
Lai Chen
Beijing Key Laboratory of Environmental Science and Engineering, School of Materials Science and Engineering, Beijing Institute of Technology, Beijing 100081, China
Chenying Zhao
Beijing Key Laboratory of Environmental Science and Engineering, School of Materials Science and Engineering, Beijing Institute of Technology, Beijing 100081, China
Yun Lu
Beijing Key Laboratory of Environmental Science and Engineering, School of Materials Science and Engineering, Beijing Institute of Technology, Beijing 100081, China
Lingyi Wan
Beijing Key Laboratory of Environmental Science and Engineering, School of Materials Science and Engineering, Beijing Institute of Technology, Beijing 100081, China
Kang Yan
Beijing Key Laboratory of Environmental Science and Engineering, School of Materials Science and Engineering, Beijing Institute of Technology, Beijing 100081, China
Youxiang Bai
Beijing Key Laboratory of Environmental Science and Engineering, School of Materials Science and Engineering, Beijing Institute of Technology, Beijing 100081, China
Zhiyu Liu
Beijing Key Laboratory of Environmental Science and Engineering, School of Materials Science and Engineering, Beijing Institute of Technology, Beijing 100081, China
Xulai Yang
Beijing Institute of Technology Chongqing Innovation Center, Chongqing 401120, China
Yuefeng Su
Beijing Key Laboratory of Environmental Science and Engineering, School of Materials Science and Engineering, Beijing Institute of Technology, Beijing 100081, China
Feng Wu
Beijing Key Laboratory of Environmental Science and Engineering, School of Materials Science and Engineering, Beijing Institute of Technology, Beijing 100081, China
The severe “shuttle effect” of dissolved polysulfide intermediates and the poor electronic conductivity of sulfur cathodes cause capacity decay of lithium–sulfur batteries and impede their commercialization. Herein, we synthesized a series of well-designed yolk-shelled Fe3O4@carbon (YS-Fe3O4@C) nanocavities with different proportions of Fe3O4 as efficient sulfur hosts to stabilize polysulfide intermediates. The yolk-shelled nanocavity architectures were prepared through a facile method, which could effectively confine the active materials and achieve high conductivity. The polysulfide intermediate shuttle was successfully suppressed by a physiochemical synergism effect combining the retention of carbon shells and the adsorption of Fe3O4 nanoparticle cores. The highly conductive carbon shell provides efficient pathways for fast electron transportation. Meanwhile, the visible evolution of active materials and a reversible electrochemical reaction are revealed by in situ X-ray diffraction. With the balanced merits of enhanced electrical conductivity of carbon shell and optimal adsorption of Fe3O4 cores, the S/YS-27Fe3O4@C cathode (Fe3O4 accounts for 27 wt% in YS-Fe3O4@C) had the best electrochemical performance, exhibiting a high reversible specific capacity of 731.9 mAh g−1 and long cycle performance at 1 C (capacity fading rate of 0.03% over 200 cycles).
