钴基沸石咪唑酯骨架结构衍生物锂硫电池正极材料  

Derivative of cobalt-based zeolitic imidazolate framework for cathode material of lithium-sulfur batteries

作　　者：洪轶伦 丛健伟 石明晨 陈江南 杨晖[1] 刘晓敏[1] HONG Yilun;CONG Jianwei;SHI Mingchen;CHEN Jiangnan;YANG Hui;LIU Xiaomin(College of Materials Science and Engineering, Nanjing Tech University, Nanjing 211800, China)

机构地区：[1]南京工业大学材料科学与工程学院,江苏南京211800

出　　处：《南京工业大学学报（自然科学版）》2021年第1期40-46,共7页Journal of Nanjing Tech University(Natural Science Edition)

基　　金：国家自然科学基金(21573109,21206069)。

摘　　要：通过原位复合法合成沸石咪唑酯骨架结构材料(ZIF-67),经高温碳化生成含钴的氮掺杂碳多面体(Co-NC),然后通过热熔融渗硫方法制得钴基沸石咪唑酯骨架结构衍生物(S@CoS2-NC)复合材料,以此复合材料作为锂硫电池的正极材料。采用X线衍射仪(XRD)、场发射扫描电子显微镜(FESEM)、能谱仪(EDS)、N2吸附-脱附分析仪、热重分析仪(TGA)、X线光电子能谱仪(XPS)以及电化学测试等手段对不同样品进行表征分析并测试其电化学性能。结果表明:在0.2C倍率下S@CoS2-NC/1(制备ZIF-67时反应6 h)复合正极的首次放电比容量最高达1129 mA·h/g,100次充放电循环后容量的保持率为66.61%,相比S@CoS2-NC/2(反应12 h)、S@CoS2-NC/3(反应24 h)复合正极和纯硫正极,比表面积和孔容最大的载体碳骨架经热熔融渗硫后生成的S@CoS2-NC/1复合正极拥有更优良的容量和循环稳定性。Zeolitic imidazolate framework(ZIF-67)was synthesized by in-situ compositing,and the cobalt-based zeolitic imidazolate framework(Co-NC)was formed by high temperature carbonization from ZIF-67.Derivative of cobalt-based zeolitic imidazolate framework(S@CoS2-NC)composite material was prepared by hot melt sulfurization,which was used as cathode material of lithium-sulfur batteries.The analysis,characterization,and electrochemical performance of these composites were investigated by X-ray diffraction(XRD),field emission scanning electron microscope(FESEM),energy dispersive spectroscopy(EDS),nitrogen adsorption-desorption analysis,thermogravimetric analysis(TGA),X-ray photoelectron spectroscopy(XPS)and electrochemical test.Results showed that the initial discharge specific capacity of S@CoS2-NC/1(reacted for 6 h when preparing ZIF-67)composite cathode was as high as 1129 mA·h/g at 0.2C rate.And the capacity retention rate was 66.61%after 100 cycles.Compared with S@CoS2-NC/2(reacted for 12 h),S@CoS2-NC/3(reacted for 24 h)composite cathodes and the S cathode,the S@CoS2-NC/1 composite cathode formed by hot melt sulfurization of the carbon skeleton with the largest specific surface area and pore volume had better capacity and cycle stability.

关 键 词：锂硫电池 沸石咪唑酯骨架结构材料 S@CoS2-NC复合材料 活性物质S 正极材料 

分 类 号：TM910.4[电气工程—电力电子与电力传动]