Due to its high capacity (1675 mAh g-1), Li-S batteries have been considered as one of the ideal energy storage systems. The grand challenges of lithium-sulfur batteries are sulfur immobilization and improving electrical conductivity of cathode composite. The carbon-sulfur (C-S) composites and the polar materials (Ni(OH)2, TiO2, MnO2, TiS2, Co9S8, etc) integration have been proven to be two of the most effective routes to achieving good Li-S battery performance. However, each strategy has drawbacks: the C-S composites have low volume density and the polar materials are often lack of electrical conductivity. Therefore, the hybridization of carbon and polar materials shall provide synergistic effects achieving ideal sulfur cathode. Herein, a hybrid material with carbon-coated NiS nanoparticles grown on graphene sheets was synthesized through a hydrothermal reaction followed by two steps of annealing. The obtained composite has a well-balanced ratio between graphene and NiS. An optimized energy density was demonstrated in lithium-sulfur cells.

中文翻译：

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金属有机框架 (MOF) 衍生的碳包覆 NiS 纳米颗粒锚定在石墨烯层上，用于高性能 Li-S 正极材料

由于其高容量（1675 mAh g-1），锂硫电池被认为是理想的储能系统之一。锂硫电池的重大挑战是硫固定和提高正极复合材料的导电性。碳硫 (CS) 复合材料和极性材料（Ni(OH)2、TiO2、MnO2、TiS2、Co9S8 等）的集成已被证明是实现良好 Li-S 电池性能的两种最有效途径。然而，每种策略都有缺点：CS 复合材料的体积密度低，极性材料通常缺乏导电性。因此，碳和极性材料的杂化应提供协同效应，实现理想的硫正极。在此处，通过水热反应和两步退火合成了一种在石墨烯片上生长的碳包覆 NiS 纳米颗粒的混合材料。获得的复合材料在石墨烯和 NiS 之间具有良好平衡的比例。在锂硫电池中证明了优化的能量密度。