The high specific capacity and energy density of lithium–sulfur batteries have attracted strong considerations on their fundamental mechanism and energy applications. However, polysulfide shuttle is still the key issue that impedes the development of Li–S batteries. Exploring nanocrystal hosts for polysulfide immobilization and conversion is a promising way. In this contribution, we have investigated well-dispersed Co₉S₈ nanocrystals grown on graphene oxide (GO) nanosheets with different degrees of dispersion as cathode host materials for Li–S batteries. The Co₉S₈-GO composite with 1 wt% GO (GCS1) has an average crystal size of 76 nm and shows the strongest adsorption capability toward lithium polysulfides. When used as the host material for the cathode of Li–S batteries, the GCS1-sulfur composite exhibits an initial specific capacity of ~1000 mAh g⁻¹ at 0.5 C and shows an average decay rate of 0.11% for 500 cycles. This work on the dispersion control of Co₉S₈ nanocrystals may inspire more investigations on well-dispersed nanocrystal based hosts for Li–S batteries.

锂硫电池的高比容量和能量密度在其基本机理和能量应用方面引起了强烈的考虑。但是，多硫化物穿梭仍然是阻碍Li-S电池发展的关键问题。探索用于多硫化物固定和转化的纳米晶体宿主是一种有前途的方法。在这项贡献中，我们研究了在分散程度不同的氧化石墨烯（GO）纳米片上生长的，分散良好的Co ₉ S ₈纳米晶体，作为Li-S电池的阴极主体材料。Co ₉ S ₈具有1 wt％的GO（GCS1）的-GO复合材料的平均晶体尺寸为76 nm，并且显示出对多硫化锂的最强吸附能力。当用作Li-S电池阴极的主体材料时，GCS1-硫复合材料在0.5 C时的初始比容量为〜1000 mAh g ^-1，在500个循环中的平均衰减率为0.11％。这项有关Co ₉ S ₈纳米晶体的分散控制的工作可能会激发人们对锂离子电池基于分散良好的纳米晶体基质的更多研究。