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超级电容器用石墨烯及其复合材料的研究重庆大学硕士学位论文（学术学位）学生姓名：宋宏芳指导教师：李新禄副教授专业：材料科学与工程学科门类：工学重庆大学材料科学与工程学院二O一三年五月InvestgationonGrapheneandItsCompositeMaterialsforSupercapacitorsAThesisSubmittedtoChongqingUniversityinPartialFulfillmentoftheRequirementfortheMaster’sDegreeofEngineeringBySongHongfangSupervisedbyAss.Prof.LiXinluSpecialty:MaterialsScienceandEngineeringSchoolofMaterialsScienceandEngineering,ChongqingUniversity,Chongqing,ChinaMay,2013中文摘要I摘要超级电容器具有较高的功率密度和能量密度等优点，成为当前广泛研究的新型能量存储器件。超级电容器的性能主要取决于电极材料，多孔碳，导电聚合物和过渡金属氧化物被广泛地用作超级电容器的电极材料。石墨烯纳米片由于具有的热稳定性、高比表面积、优良的导电性，成为超级电容器最有发展前景的电极材料之一。本论文主要着眼于石墨烯及其石墨烯基复合材料的合成、微观结构表征及其超电容的反应性能。主要研究内容如下：本文分别采用高温膨胀和微波辐射制备石墨烯纳米片。系统地研究了两种剥离方法对石墨烯的表面结构和电化学性能的影响。N2吸附结果表明，高温膨胀剥离的石墨烯纳米片的比表面积和孔体积均大于的微波辐射得到的产品。电容测试结果表明，高温膨胀剥离的石墨烯纳米片在电流密度为0.1A/g时，比容量可达到188F/g。本文通过原位聚合法制备出具有三维（3-D）骨架结构的聚苯胺/石墨烯纳米片复合材料。微观结构的分析表明，当苯胺浓度低时，聚苯胺均匀沉积在石墨烯纳米片的表面上，但当苯胺浓度高时聚苯胺趋向于在石墨烯纳米片之间团聚。电化学性能测试表明，未被破坏框架结构的石墨烯纳米片有效地提高了复合材料的电化学电容。在电流密度为0.1A/g时，空白样石墨烯的比容量为190.6F/g，聚苯胺/石墨烯纳米片的复合材料（聚苯胺含量低）的比电容达到261.4F/g。本文从材料的结构设计出发，采用原位生长法将针状二氧化锰阵列树立在石墨烯上，构筑成三明治式结构。该制备方法利用高锰酸钾和石墨烯之间的氧化还原反应，工艺简单有效。石墨烯不仅可以提供电化学反应的电子通道，也充当二氧化锰纳米线阵列的柔性衬底，而二氧化锰纳米线阵列作为高容量的提供者，促进电解液离子的渗透。复合材料具有高电容性能（0.5Ag-1时可达276Fg-1），优良的倍率的能力（60Ag-1时62.7％容量保持率），同时保持良好的循环稳定性（1200次后没有衰减），最大功率密度达到21.6kWkg-1。关键词：超级电容器，电极材料，石墨烯纳米片，聚苯胺，二氧化锰重庆大学硕士学位论文II英文摘要IIIABSTRACTSupercapacitors(SCs),havebeenstudiedextensivelyinthepastfewdecadesasenergystoragedevicesduetotheirhigherpowerdensityandhigherenergydensity.TheperformanceofSCsdependsprincipallyonelectrodematerials.Porouscarbonmaterials,conductingpolymersandtransition-metaloxidesarewidelyusedaselectrodematerialsforsupercapacitors.Currently,graphenenanosheets(GNS)havebeenregardedasoneofthemostpromisingcandidatematerialforsupercapacitorowningtoexceptionalthermalstability,highsurfacearea,andexcellentconductivity.Thedissertationfocusesonthesynthesis,themicrostructureandtheelectrochemicalperformanceofgrapheneanditscompositematerials.Themainresultsaresummarizedasfollows:Inthisdissertation,graphenenanosheets(GNS)wereexfoliatedbythermalexpansionandmicrowaveirradiation,respectively.TheinfluenceofexpansionmethodsonGNS’ssurfacestructureandelectrochemicalpropertyweresystemicallyanalyzed.TheN2adsorptionresultsprovedthatboththespecificsurfaceareaandporevolumeoftheGNSexfoliatedbythermalexpansionarelargerthanthosebymicrowaveirradiation.TheresultsshowedthattheGNSviathermalexpansionexhibitedbetterelectrochemicalpropertywiththespecificcapacityof188F/gatthecurrentdensityof0.1A/g.Acompositeofpolyaniline(PANI)andgraphenenanosheets(GNS)withthree-dimensional(3-D)frameworkstructurewaspreparedviainsitupolymerization.ThemicrostructureanalysisindicatesthatthePANIhomogeneouslydepositsonthesurfaceofGNSatlowcontentbuttendtoaggregatebetweenGNSathighcontent.TheelectrochemicalperformanceshowthattheGNSwithundestroyedframeworkareeffectivetoenhancetheelectrochemicalcapacitanceofthecomposite.Aremarkablespecificcapacitanceof261.4F/g(basedonGNS/PANIcompositeswithlowcontentofPANI)isobtainedatacurrentdensityof100mA/gcomparedto190.6F/gforpureGNS.Basedonthematerialstructuredesign,a3Dnanoarchitectureoffree-standingneedle-likeMnO2arrays-graphene(FNMRG)wascreatedbyin-situgrowthofMnO2sandwichedbetweengraphenenanosheets(GNS).Thepreparationisasimplebuteffectiveredoxreplacementreactionbetweenpotassiumpermanganate(KMnO4)andGNS.GNScannotonlyprovidetheelectrontransportationforthecapacitancereactions重庆大学硕士学位论文IVbutalsoactasaflexiblesubstratefortheMnO2nanowirearrays,whiletheMnO2nanowirearraysserveashigh-capacityhostsandfacilitatetheelectrolyteionpenetration.Thecompositeexhibithigh-capacitanceperformance(276Fg-1at0.5Ag-1),excellentratecapability(62.7%capacityretentionat60Ag-1),meanwhilemaintaininganexcellentcyclingstability(nodegradationafter1200cycles)andamaximumpowerdensityof21.6kWkg-1.Keywords:Supercapacitors,Electrodematerials,Graphenenanosheets,polyaniline,MnO2目录V目录中文摘要···········································································································I英文摘要·········································································································III1绪论···········································································································11.1引言·············································································································11.2超级电容器····································································································31.2.1超级电容器的简介····················································································31.2.2超级电容器工作原理·················································································41.2.3超级电容器的构造····················································································61.2.4超级电容器的电极材料研究········································································71.3本论文研究意义及主要研究内容·····································································171.3.1研究意义·······························································································171.3.2主要研究内容············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