Remarkable chemical adsorption and catalysis of monodisperse metallic cobalt sulfide nanoparticles enable long-cycling Li-S battery with high areal capacity and low shuttle constant
Remarkable chemical adsorption and catalysis of monodisperse metallic cobalt sulfide nanoparticles enable long-cycling Li-S battery with high areal capacity and low shuttle constant
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DOI：
10.1016/j.energy.2023.129751
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发表时间：
2023-12-01
期刊：
影响因子：
9
通讯作者：
Zhou，Yingke
中科院分区：
文献类型：
--
作者：
Tian，Xiaohui;Che，Lukang;Zhou，Yingke
高能量密度锂硫电池被认为是最具潜力的新一代储能技术之一。然而，由于硫的体积变化严重，中间多硫化物的溶解和氧化还原动力学缓慢，以及锂负极的不稳定性，导致容量迅速衰减。为此，设计了一种新型的由石墨烯气凝胶和极性Co9S8纳米粒子组成的高导电性多孔硫磺阴极主体。多孔导电骨架不仅为电子和锂离子的快速传导提供了通道，而且还提供了足够的空间来物理限制多硫化锂并适应体积膨胀。实验和理论计算都表明，原位均匀沉积的Co9S8纳米粒子能够有效地结合极性多硫化物并催化它们之间的相互转化，从而有效地抑制了穿梭效应。Co9S8-GA/S正极材料在0.1C下表现出高的比放电容量(1219.1 mAhg−1)和高的面比容量(14.3mAhm−2)，较低的穿梭常数(0.15h−1)，优异的倍率性能(625.6 mAhg−1/7.4mAhm−2at 5℃)，出色的长循环稳定性(在2℃下1000次循环的低衰减率为0.024%/循环)。本研究展示了一种设计高性能锂硫电池复合正极的气凝胶策略。
High-energy density lithium-sulfur battery is considered as one of the most potential new-generation energy-storage technologies. Nevertheless, the capacity decays rapidly due to severe volumetric change of sulfur, dissolution and slow redox kinetics of intermediate polysulfides, and instability of lithium anode. Herein, a novel highly conductive porous sulfur cathode host composed of graphene aerogel and polar Co9S8nanoparticle is designed to address these obstacles. The porous conductive framework not only provides channels for rapid conduction of electron and lithium ion, but also provides adequate space to physically confine the lithium polysulfides and accommodate the volume expansion. Both experimental and theoretical calculations demonstrate that the in-situ uniformly deposited Co9S8nanoparticles can effectively bind polar lithium polysulfides and catalyze their interconversion, and the shuttle effect is therefore effectively suppressed. The Co9S8-GA/S cathode exhibits high specific discharge capacity (1219.1 mAh g−1) and high areal specific capacity (14.3 mAh m−2) at 0.1 C, low shuttle constant (0.15 h−1), excellent rate performance (625.6 mAh g−1/7.4 mAh m−2at 5 C), outstanding long cyclic stability (low decay of 0.024 %/cycle during 1000 cycles at 2 C). This study demonstrates a promising aerogel strategy to design high-performance composite cathode for lithium-sulfur battery.