The Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA.
J Am Chem Soc. 2011 Nov 23;133(46):18522-5. doi: 10.1021/ja206955k. Epub 2011 Nov 1.
The loss of sulfur cathode material as a result of polysulfide dissolution causes significant capacity fading in rechargeable lithium/sulfur cells. Here, we use a chemical approach to immobilize sulfur and lithium polysulfides via the reactive functional groups on graphene oxide. This approach enabled us to obtain a uniform and thin (around tens of nanometers) sulfur coating on graphene oxide sheets by a simple chemical reaction-deposition strategy and a subsequent low-temperature thermal treatment process. Strong interaction between graphene oxide and sulfur or polysulfides enabled us to demonstrate lithium/sulfur cells with a high reversible capacity of 950-1400 mA h g(-1), and stable cycling for more than 50 deep cycles at 0.1C (1C = 1675 mA g(-1)).
硫阴极材料因多硫化物溶解而损失，导致可充电锂/硫电池的容量显著下降。在这里，我们使用一种化学方法通过氧化石墨烯上的反应性官能团来固定硫和多硫化锂。通过简单的化学反应-沉积策略和随后的低温热处理过程，我们能够在氧化石墨烯片上获得均匀且薄（约几十纳米）的硫涂层。氧化石墨烯与硫或多硫化物之间的强相互作用使我们能够展示具有 950-1400 mA h g(-1)高可逆容量和超过 50 次在 0.1C（1C = 1675 mA g(-1))下深度循环稳定的锂/硫电池。
