Nitrogen‐Doped Graphene‐Supported Mixed Transition‐Metal Oxide Porous Particles to Confine Polysulfides for Lithium–Sulfur Batteries |
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Authors: | Qian Sun Baojuan Xi Jiang‐Ying Li Hongzhi Mao Xiaojian Ma Jianwen Liang Jinkui Feng Shenglin Xiong |
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Institution: | 1. Key Laboratory of the Colloid and Interface Chemistry, Ministry of Education, and School of Chemistry and Chemical Engineering, Shandong University, Jinan, P. R. China;2. College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou, P. R. China;3. Department of Chemistry, University of Science and Technology of China, Hefei, P. R. China;4. Key Laboratory for Liquid‐Solid Structural Evolution & Processing of Materials (Ministry of Education), School of Materials Science and Engineering, Shandong University, Jinan, P. R. China |
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Abstract: | The intricate charge–discharge reactions and bad conductivity nature of sulfur determine the extreme importance of cathode engineering for Li–S batteries. Herein, spinel ZnCo2O4 porous particles@N‐doped reduced graphene oxide (ZnCo2O4@N‐RGO) are prepared via the combined procedures of refluxing and hydrothermal treatment, consisting of interconnected uniform ZnCo2O4 nanocubes with an average size of 5 nm anchored on graphene nanosheets. The as‐obtained composite can act as an inimitable cathode scaffold to suppress the shuttling of polysulfides by chemical confinement of ZnCo2O4 and N‐RGO for the first time, as demonstrated by the adsorption energy of ZnCo2O4 to Li2S4 via the strong chemical bonding between Zn or Co and S. The RGO nanosheets with a relatively high specific surface area provide a good conductive network and structural stability. The introduction of doped N atoms and numerous ZnCo2O4 porous nanoparticles can inhibit the transfer of lithium polysulfides between the cathode and anode. Due to the unique structural and compositional features, the as‐obtained hybrid materials with the high sulfur loading of 71% and even 82% still deliver high specific capacity, good rate capability, and enhanced cycling stability with exceptionally high initial Coulombic efficiency, which displays a high utilization of sulfur. |
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Keywords: | chemical confinement Li– S batteries nitrogen‐doped reduced graphene oxides ZnCo2O4 nanocubes |
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