摘要
The ultrahigh specific energy density and low cost of lithium-sulfur batteries are suitable for the next generation of energy storage.However,the shuttle issue and sluggish conversion kinetics of polysulfides remain unsolved.Confining metal nanoclusters with strong polarity in conductive porous carbon is an effective strategy for tackling such knotty issues.Herein,we design and synthesize hollow cubic carbon embedded with highly dispersed cobalt nanoclusters as an effective sulfur reservoir for lithium sulfur batteries.The large cavity structure and well-dispersed cobalt nanoclusters,with uniform sizes near 11 nm,enable the hosting structure to hold the high sulfur loading,70%capacity retention after 500 cycles at 2 C with a high sulfur loading of 6.5 mg·cm^(−2),effective stress release,accelerated polysulfide conversion,superior rate performance,strong physical confinement and chemical absorption capability.Further density functional theoretical calculations demonstrate that the welldispersed cobalt nanoclusters in the hosting structure play a critical electrocatalytic role in boosting the capability of absorbing and converting polysulfides.
基金
supported by the National Key Research and Development Program of China(No.2017YFA0208200)
the Fundamental Research Funds for the Central Universities of China(No.0205-14380219)
the National Natural Science Foundation of China(Nos.22109069,22022505,21872069,21802119,and 21808195)
the Natural Science Foundation of Jiangsu Province(Nos.BK20181056 and BK20180008)
the Funding For School-Level Research Projects of Yancheng Institute of Technology(Nos.xjr2019006,and xjr2019055)
the 2021 Suzhou Gusu Leading Talents of Science and Technology Innovation and Entrepreneurship in Wujiang District,the Open Fund of Key Laboratory for Advanced Technology in Environmental Protection of Jiangsu Province and some enterprise projects(Nos.WJGTT-XT3,19KJA540001,and JNHB068).
