Yuan Shouyi, Guo Ziyang, Wang Lina, Hu Shuang, Wang Yonggang, Xia Yongyao
Department of Chemistry Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials Institute of New Energy iChEM (Collaborative Innovation Center of Chemistry for Energy Materials) Fudan University Shanghai 200433 P.R. China.
Adv Sci (Weinh). 2015 Jun 10;2(8):1500071. doi: 10.1002/advs.201500071. eCollection 2015 Aug.
Carbon/sulfur composites are attracting extensive attention because of their improved performances for Li-S batteries. However, the achievements are generally based on the low S-content in the composites and the low S-loading on the electrode. Herein, a leaf-like graphene oxide (GO), which includes an inherent carbon nanotube midrib in the GO plane, is synthesized for preparing GO/S composites. Owing to the inherent high conductivity of carbon nanotube midribs and the abundant surface groups of GO for S-immobilization, the composite with an S-content of 60 wt% exhibits ultralong cycling stability over 1000 times with a low capacity decay of 0.033% per cycle and a high rate up to 4. When the S-content is increased to 75 wt%, the composite still shows a perfect cycling performance over 1000 cycles. Even with the high S-loading of 2.7 mg cm on the electrode and the high S-content of 85 wt%, it still shows a promising cycling performance over 600 cycles.
碳/硫复合材料因其在锂硫电池中的性能提升而备受广泛关注。然而，这些成果通常基于复合材料中低硫含量以及电极上低硫负载量。在此，合成了一种叶状氧化石墨烯（GO），其在GO平面内包含一条固有的碳纳米管中脉，用于制备GO/S复合材料。由于碳纳米管中脉固有的高导电性以及GO表面丰富的用于固定硫的基团，硫含量为60 wt%的复合材料表现出超过1000次的超长循环稳定性，每循环的容量衰减低至0.033%，并且高达4倍率时仍具有高倍率性能。当硫含量增加到75 wt%时，该复合材料在1000次循环中仍表现出完美的循环性能。即使在电极上硫负载量高达2.7 mg cm且硫含量为85 wt%的情况下，它在600次循环中仍表现出有前景的循环性能。
