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摘要I摘要碳纳米管(CarbonNanotubes，CNTs)具有窄孔径分布、高比表面积利用率、高电导率和高稳定性,，被认为是为超级电容器电极材料的理想电极材料之一。而取向碳纳米管阵列(CarbonNanotubeArray，CNTA)由于CNTs的独特的排列方式更加适合在超级电容器中的应用。在本论文中，分别制备CNTA电极、MnO2电极、CNT/MnO2复合电极和CNTA/MnO2复合电极，并在0.5mol/LNa2SO4电解液中进行电化学特性测试和分析。通过一系列的实验，得到以下结论：1)碳纳米管阵列电极在0.63mA电流下的比电容为4.34mF/cm2(大约8.68F/g)，其等效串联电阻为1.3Ω。2)二氧化锰电极在0.63mA电流密度下比电容为984.4mF/cm2(或82.0F/g)，其等效串联电阻分别为83.5Ω；其充放电曲线具有明显的近似三角形的对称性分布，表明电极反应的可逆性好。3)加入碳纳米管的MnO2电极(CNT/MnO2)的比电容高于MnO2电极，同时具有更小的内阻，说明MnO2电极中加入碳纳米管，会明显的降低MnO2电极的等效串联电阻。4)二氧化锰沉积时间分别为60min和120min的CNTA/MnO2复合电极(CM-60和CM-120)在1.25mA下比电容分别为91.3F/g和67.8F/g，等效串联电阻分别为12.5Ω和20.9Ω。因此，二氧化锰的沉积时间过长不利于制备高容量和低内阻的复合电极，同时还会影响二氧化锰和碳纳米管阵列的附着性。5)CNTA/MnO2复合电极的比容量大于MnO2电极，同时具备较低内阻，说明采用碳纳米管与二氧化锰的复合材料作为超大容量电容器的电极，既可以改善MnO2半导体的导电性能，又可以产生较大的法拉第准电容。关键词：超级电容器，碳纳米管阵列，二氧化锰，复合电极材料，电化学特性AbstractIIAbstractCarbonNanotubes(CNTs)areregardedasanidealelectrodematerialforsupercapacitors,asaresultoftheirnarrowporedistribution,largespecificsurfacearea,excellentconductivityandhighelectrochemicalstability.ComparedwithCNTs,CarbonNanotubeArrays(CNTAs)aremoresuitableforapplicationinsupercapacitors,duetotheuniquearrangementofCNTsinCNTAs.Inthisdissertation,CNTAelectrode,MnO2electrodeandCNT/MnO2compositeelectrode,aswellasCNTA/MnO2compositeelectrodewerefabricated,respectively,andtheirelectrochemicalpropertieswereinvestigatedin0.5mol/LNa2SO4electrolyte.Throughaseriesofexperiments,thefollowingconclusionsweredrawn：1)CNTAelectrodeprovidedspecificcapacitanceof4.34mF/cm2(~8.68F/g)at0.63mA,withEquivalentSeriesResistance(ESR)of1.3Ω.2)MnO2electrode,withhighESRof83.5Ω,hadspecificcapacitanceof984.4mF/cm2(~82.0F/g)at0.63mA,anditschargeanddischargecurveillustratedanobvioussymmetryoftheapproximatelytriangulardistribution,presentingagoodreversibilityoftheelectrodereaction.3)ComparedwithMnO2electrode,MnO2electrodewithCNT(CNT/MnO2electrode)showedhigherspecificcapacitanceandlowerESR.Therefore,byaddingCNT,theESRofMnO2electrodewasevidentlyreduced.4)CNTA/MnO2electrodeswith60minand120mindepositiontimeofMnO2(labeledCM-60andCM-120)hadspecificcapacitanceof91.3F/gand67.8F/g,andESRof12.5Ωand20.9Ω,respectively.Asaconsequence,extremelylongdepositiontimewentagainstthefabricationofelectrodewithhighspecificcapacitanceandlowESR.Inaddition,itcouldcriticallyinfluencetheadhesionofCNTAandMnO2.5)CNTA/MnO2compositeelectrodecouldprovidehigherspecificcapacitanceandlowerESRthanMnO2electrode,indicatingthatCNTA/MnO2compoundmaterialasanelectrodematerialofsupercapacitorsnotonlyimprovestheconductivityofMnO2,butalsoproducespseudo-capacitorswithhighcapacitance.Keywords:Supercapacitors,CarbonNanotubeArrays,Manganesedioxide,Compositeelectrode,Electrochemicalproperties目录III目录第一章引言..........................................................11.1超级电容器................................................................................................................11.1.1超级电容器的特点.................................................................................................11.1.2超级电容器的研究意义及发展概况.....................................................................31.2基于碳纳米管阵列的电极材料研究现状和趋势....................................................31.2.1定向碳纳米管阵列.................................................................................................41.2.2碳纳米管阵列与金属氧化物的复合.....................................................................41.2.3研究趋势.................................................................................................................41.3本论文的研究背景、工作内容及意义....................................................................5第二章超级电容器的结构和工作原理.........................................................................62.1超级电容器的结构....................................................................................................62.1.1电极材料.................................................................................................................62.1.2电解液.....................................................................................................................72.1.3集电极和隔膜.........................................................................................................82.1.4超级电容器外壳.....................................................................................................82.2超级电容器工作原理................................................................................................82.2.1双电层电容器的工作原理.....................................................................................92.2.2法拉第准电容器的工作原理...............................................................................102.3本章小结..................................................................................................................11第三章实验方法和测试方法.......................................................................................123.1主要试剂和仪器设备..............................................................................................123.1.1主要试剂及原材料...............................................................................................123.1.2主要实验仪器.............................................