The exploration of new catalytic hosts is highly important to tackle the sluggish electrochemical kinetics of sulfur redox for achieving high energy density of lithium-sulfur batteries.Herein,for the first time,we present high-entropy oxide(HEO,(Mg0.2Mn0.2Ni0.2Co0.2Zn0.2)Fe2O4)nanofibers as catalytic host of sulfur.The HEO nanofibers show a synergistic effect among multiple metal cations in spinel structure that enables strong chemical confinement of soluble polysulfides and fast kinetics for polysulfide conversion.Consequently,the S/HEO composite displays the high gravimetric capacity of 1368.7 mAh g-1 at 0.1 C rate,excellent rate capability with the discharge capacity of 632.1 mAh g-1 at 5 C rate,and desirable cycle stability.Furthermore,the S/HEO composite shows desirable sulfur utilization and good cycle stability under a harsh operating condition of high sulfur loading(4.6 mg cm-2)or low electrolyte/sulfur ratio(5 μL mg-1).More impressively,the high volumetric capacity of 2627.9 mAh cm-3 is achieved simultaneously for the S/HEO composite due to the high tap density of 1.92 g cm-3,nearly 2.5 times of the conventional sulfur/carbon composite.Therefore,based on high-entropy oxide materials,this work affords a fresh concept of elevating the gravimetric/volumetric capacities of sulfur cathodes for lithium-sulfur batteries.

Liyuan Tian;Ze Zhang;Sheng Liu;Guoran Li;Xueping Gao

Institute of New Energy Material Chemistry,School of Materials Science and Engineering,Renewable Energy Conversion and Storage Center,Nankai University,Tianjin 300350,China;College of Chemistry,Key Laboratory of Jiangxi Province for Environment and Energy Catalysis,Nanchang University,Nanchang 330031,China

能源与环境材料（英文）

[1]Liyuan Tian;Ze Zhang;Sheng Liu;Guoran Li;Xueping Gao-.High-Entropy Spinel Oxide Nanofibers as Catalytic Sulfur Hosts Promise the High Gravimetric and Volumetric Capacities for Lithium-Sulfur Batteries)[J].能源与环境材料（英文）,2022(02):645-654

Gravimetric

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