J Am Chem Soc. 2013 Nov 6;135(44):16736-43. doi: 10.1021/ja409508q.
Lithium–sulfur batteries have attracted much attention in recent years due to their high theoretical capacity of 1672 mAh g(–1) and low cost. However, a rapid capacity fade is normally observed, attributed mainly to polysulfide dissolution and volume expansion. Although many strategies have been reported to prolong the cyclability, the high cost and complex preparation processes still hinder their practical application. Here, we report the synthesis of a polyaniline–sulfur yolk–shell nanocomposite through a heating vulcanization of a polyaniline–sulfur core–shell structure. We observed that this heating treatment was much more effective than chemical leaching to prepare uniform yolk–shell structures. Compared with its sulfur–polyaniline core–shell counterparts, the yolk–shell nanostructures delivered much improved cyclability owing to the presence of internal void space inside the polymer shell to accommodate the volume expansion of sulfur during lithiation. The yolk–shell material exhibited a stable capacity of 765 mAh g(–1) at 0.2 C after 200 cycles, representing a promising future for industrial scale Li–S batteries.
锂硫电池由于其高达 1672 mAh g(-1)的理论容量和低成本而在近年来受到了广泛关注。然而，通常会观察到容量迅速衰减，这主要归因于多硫化物的溶解和体积膨胀。尽管已经报道了许多策略来延长循环寿命，但其高成本和复杂的制备工艺仍然阻碍了它们的实际应用。在这里，我们通过聚苯胺-硫核壳结构的加热硫化合成了聚苯胺-硫蛋黄壳纳米复合材料。我们观察到，与化学浸出相比，这种热处理更有效地制备了均匀的蛋黄壳结构。与它们的硫-聚苯胺核壳对应物相比，由于聚合物壳内存在内部空隙空间，可以容纳硫在锂化过程中的体积膨胀，因此蛋黄壳纳米结构表现出了显著改善的循环稳定性。该蛋黄壳材料在 0.2 C 下经过 200 次循环后表现出稳定的 765 mAh g(-1)容量，为工业规模的 Li-S 电池提供了有前景的未来。
