氮掺杂及PEG包覆对CNT/S材料储锂性能的影响  

Effect of N-doping and PEG-coating on the Lithium Storage Performance of CNT/S Materials

作　　者：王宏哲[1] 肖剑荣[1] 赵航[1] 

机构地区：[1]桂林理工大学,广西桂林541004

出　　处：《稀有金属材料与工程》2017年第2期571-576,共6页Rare Metal Materials and Engineering

基　　金：国家自然科学基金(11364011;21263003)

摘　　要：以硫代氨基脲为氮源,用高温退火法对碳纳米管实现氮掺杂,利用PEG对掺氮复合材料(NCNT/S)进行外包覆。采用X射线衍射仪(XRD),扫描电子显微镜(SEM),X射线光电子能谱仪(XPS)对复合材料进行了表征。结果表明高温退火使氮有效地掺入碳纳米管中,而碳纳米管仍保持原本征形貌。电化学测试表明:掺氮后复合电极首次放电比容量明显提高,达到882.5 mAh·g^(-1),90次循环过后具有89.46%的容量保持量,而PEG包覆使掺氮复合电极首次放电比容量提高至1109.7 mAh·g^(-1),经过90次循环放电比容量仍保持在995.2 mAh·g^(-1)。这说明掺氮和PEG包覆均能很好地改善复合材料的电化学性能。The N-doped carbon nanotube was prepared by high-temperature annealing,using the thiosemicarbazide as a nitrogen source.Then,the nitrogen-doped composites（NCNT/S） were coated outside by PEG.The structure and morphology of NCNT/S were detected by X-ray diffraction（XRD）,X-ray photoelectron spectroscopy（XPS）,and scanning electron microscope（SEM）.The results show that the nitrogen atoms are effectively doped in carbon nanotubes by the high-temperature annealing method,and the carbon nanotube also maintains the intrinsic morphology and structure.Electrochemical test results indicate that the conductive properties of composite materials are enhanced by N-doping.The initial discharge capacity reaches 882.5 mAh·g^-1,and it keeps at 89.46%after 90 cycles.It is further enhanced by PEG-coating,and the initial discharge capacity increases to 1109.7 mAh·g^-1,and the discharge capacity retention ratio is 995.2 mAh·g^-1 after 90 cycles.The N-doping and PEG-coating can significantly improve the electrochemical properties of the CNT/S composite materials.

关 键 词：锂硫电池 硫代氨基脲 氮掺杂 PEG包覆 电化学性能 

分 类 号：TM912[电气工程—电力电子与电力传动]