文献类型：期刊文献

英文题名：Efficient polysulfide barrier of a graphene aerogel-carbon nanofibers-Ni network for high-energy-density lithium-sulfur batteries with ultrahigh sulfur content

作者：Zhang, Yongzheng[1];Wang, Ruochen[1];Tang, Weiqiang[2];Zhan, Liang[1];Zhao, Shuangliang[2];Kang, Qi[3];Wang, Yanli[1];Yang, Shubin[4]

机构：[1]East China Univ Sci & Technol, State Key Lab Chem Engn, Key Lab Specially Funct Polymers & Related Techno, Minist Educ,Shanghai Key Lab Multiphase Mat Chem, Shanghai 200237, Peoples R China;[2]East China Univ Sci & Technol, State Key Lab Chem Engn, Sch Chem Engn, Shanghai 200237, Peoples R China;[3]Nanjing Univ Posts & Telecommun, Key Lab Organ Elect & Informat Displays, IAM, Nanjing 210023, Jiangsu, Peoples R China;[4]Beihang Univ, Key Lab Aerosp Adv Mat & Performance, Minist Educ, Sch Mat Sci & Engn, Beijing 100191, Peoples R China

年份：2018

卷号：6

期号：42

起止页码：20926

外文期刊名：JOURNAL OF MATERIALS CHEMISTRY A

收录：;EI(收录号：20184506049012);WOS:【SCI-EXPANDED(收录号:WOS:000451600200037)】；

基金：This work was financially supported by the National Science Foundation of China (51472086, 51002051) and the CAS Key Laboratory of Carbon Materials (KLCMKFJJ1703). W. T. is grateful to the China Scholarship Council and British Council for the visiting fellowship. We also thank Dr Hu Pengfei, who serves in the Instrumental Analysis and Research Center of Shanghai University, for his help in microstructural characterization and analysis of the materials.

语种：英文

外文关键词：Chemical bonds - Cathodes - Aerogels - Electrolytes - Lithium batteries - Protective coatings - Lithium sulfur batteries - Graphene - Lithium compounds - Polysulfides

摘要：Low sulfur loading and content, as well as severe shuttle effects, remain the key issues for the application of lithium-sulfur (Li-S) batteries, resulting in a low areal capacity and fast capacity fade. Herein, a highly efficient conductive network is developed by growing herringbone structured carbon nanofibers (CNFs) on the surface of graphene aerogel (GA-CNFs-Ni) and is further applied as a functional coating layer in Li-S batteries. The conductive coating layer, serves as both a shield to trap the active materials detached from the cathode and a conductive "second current collector" to reactivate the trapped active materials. The herringbone structured CNFs enriched with defects and gaps enlarge the available reaction site for electrons, the electrolyte and sulfur species, ensuring the smooth operation of the sulfur cathode with high loading and high content. In addition, the uniformly distributed Ni nanoparticles also exert strong chemical bonding with polysulfides by first-principle calculations. Consequently, the GA-CNFs-Ni coated separator enables the "double high" sulfur cathode (5 mg cm(-2), 90 wt%) to display an ultrastable cycle capability and superior rate performance. Moreover, a high sulfur loading of 10 mg cm(-2) and a low electrolyte/sulfur (E/S) ratio (6 mL mg(-1)) are obtained, delivering a high areal capacity of 5.5 mA h cm(-2) after 60 cycles.