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ContentIntroductiontographene.PreparationandcharacterizationgraphenePotentialapplicationofgrapheneConclusionsGrapheneisaone-atom-thickplanarsheetofsp2-bondedcarbonatomsthataredenselypackedinahoneycombcrystallattice石墨烯是sp2键合的碳原子的单原子厚的平面片，其紧密地包装在蜂窝状晶格中Thename‘graphene’comesfromgraphite+-ene=grapheneHighresolutiontransmissionelectronmicroscopeimages(TEM)ofgrapheneIntroductiontographeneMolecularstructureofgrapheneA.K.Geim&K.S.Novoselov.Theriseofgraphene.NatureMaterialsVol.6,183-191(2007).IntroductionIntroduction-Electronicproperties电性能-Thermalproperties热性能-Mechanicalproperties机械-Opticalproperties光性能-Relativisticchargecarriers相对电荷载体AnomalousquantumHalleffect异常量子霍尔效应PropertiesofgrapheneElectronicproperties-Highelectronmobility(atroomtemperature~200.000cm2/(V·s),,ex.SiatRT~1400cm2/(V·s),carbonnanotube:~100.000cm2/(V·s),organicsemiconductors(polymer,oligomer):10cm2/(V·s)-Resistivityofthegraphenesheet~10−6Ω·cm,lessthantheresistivityofsilver(Ag),thelowestresistivitysubstanceknownatroomtemperature(electricalresistivityisalsoastheinverseoftheconductivityσ(sigma),ofthematerial,orWhereυdisthedriftvelocityinm/s(SIunits)EistheappliedelectricfieldinV/m(SI)µisthemobilityinm2/(V·s),inSIunits.IntroductionPropertiesofgraphene-HighYoung’smodulus(~1,100Gpa)高杨氏模量Highfracturestrength(125Gpa)高断裂强度-Monolayergrapheneabsorbsπα≈2.3%ofwhitelight(97.7%transmittance),whereαisthefine-structureconstant.MechanicalpropertiesOpticalpropertiesArepresentationofadiamondtipwithatwonanometerradiusindentingintoasingleatomicsheetofgraphene(Science,321(5887):385)-Grapheneisasthestrongestmaterialevermeasured,some200timesstrongerthanstructuralsteel石墨烯是最强的材料，比结构钢强200倍BriefhistoryofgrapheneThetermgraphenefirstappearedin1987todescribesinglesheetsofgraphiteasoneoftheconstituentsofgraphiteintercalationcompounds(GICs).Largergraphenemoleculesorsheets(sothattheycanbeconsideredastrueisolated2Dcrystals)cannotbegrowneveninprinciple.Inthe1930s,LandauandPeierls(andMermin,later)showedthermodynamicsprevented2-dcrystalsinfreestate,anarticleinPhysicsTodayreads:术语石墨烯首次出现在1987年，描述单石墨作为石墨层间化合物（GIC）的成分之一。更大的石墨烯分子或片（使得它们可以被认为是真正隔离的2D晶体）甚至在原理上也不能生长。在20世纪30年代，Landau和Peierls（和Mermin，后来）显示热力学阻止2-d晶体在自由状态，物理今天的一篇文章Fundamentalforcesplaceseeminglyinsurmountablebarriersinthewayofcreating[2Dcrystals]...Nascent2Dcrystallitestrytominimizetheirsurfaceenergyandinevitablymorphintooneoftherichvarietyofstable3Dstructuresthatoccurinsoot.Butthereisawayaroundtheproblem.Interactionswith3Dstructuresstabilize2Dcrystalsduringgrowth.Soonecanmake2Dcrystalssandwichedbetweenorplacedontopoftheatomicplanesofabulkcrystal.Inthatrespect,graphenealreadyexistswithingraphite...OnecanthenhopetofoolNatureandextractsingle-atom-thickcrystallitesatalowenoughtemperaturethattheyremaininthequenchedstateprescribedbytheoriginalhigher-temperature3Dgrowth.”基本力量在创建[2D晶体]的方式中存在看似不可逾越的障碍...新颖的2D微晶试图最小化其表面能，并且不可避免地变成在烟炱中发生的丰富多样的稳定的3D结构之一。但是有一个解决问题的方法。与3D结构的相互作用在生长期间稳定2D晶体。因此，可以使2D晶体夹在块体晶体的原子平面之间或放置在其上。在这方面，石墨烯已经存在于石墨中...然后，人们可以希望愚弄自然，并在足够低的温度下提取单原子厚的微晶，使得它们保持在由原始的较高温度的3D生长规定的淬火状态。•In2004:AndreGeimandKostyaNovoselovatManchesterUniversitymanagedtoextractsingle-atom-thickcrystallites(graphene)frombulkgraphite:Pulledoutgraphenelayersfromgraphiteandtransferredthemontothinsilicondioxideonasiliconwaferinaprocesssometimescalledmicromechanicalcleavageor,simply,theScotchtapetechnique.Since2004,anexplosionintheinvestigationofgrapheneintermofsynthesis,characterization,propertiesaswellasspecificalpotentialapplicationwerereported.•在2004年：曼彻斯特大学的AndreGeim和KostyaNovoselov设法从块状石墨中提取单原子厚的微晶（石墨烯）：从石墨中拉出石墨烯层，并将其转移到硅晶片上的薄二氧化硅上，有时称为微机械切割，或简单地，苏格兰带技术。自2004年以来，报告了石墨烯在合成，表征，性质以及特异性潜在应用方面的研究中的爆炸。PreparationandcharacterizationgraphenePreparationmethodsTop-downapproach(Fromgraphite)自上而下的方法Bottomupapproach自下而上的方法（来自碳前体）(fromcarbonprecursors)-Bychemicalvapourdeposition(CVD)ofhydrocarbon-ByepitaxialgrowthonelectricallyinsulatingsurfacessuchasSiC-TotalOrganicSynthesis-Micromechanicalexfoliationofgraphite(Scotchtapeorpeel-offmethod)-Creationofcolloidalsuspensionsfromgraphiteoxideorgraphiteintercalationcompounds(GICs)Ref:Carbon,48,2127–2150(2010)制备方法•-石墨的微机械剥离（胶带或剥离法）-由氧化石墨或石墨层间化合物（GIC）形成胶体悬浮液•-通过烃的化学气相沉积（CVD）•-通过在电绝缘表面上外延生长例如SiC•-总有机合成Characterizationmethods表征方法ScanningProbeMicroscopy(SPM):-Atomicforcemicroscopes(AFMs)-Scanningtunnelingmicroscopy(STM)RamanSpectroscopyTransmissionelectronMicroscopy(TEM)X-raydiffraction(XRD)AtomicforcemicroscopyimagesofagraphiteoxidefilmdepositedbyLangmuir-BlodgettassemblyTEMimagesshowthenucleationof(c)one,(d)three,or(e)fourlayersduringthegrowthprocessRamanSpectroscopyTransmissionelectronMicroscopy(TEM)XRDpatternsof400umdiametergraphiteflakesoxidizedforvariouslengthsoftime.X-raydiffraction(XRD)Top-downapproach(Fromgraphite)GraphiteoxidemethodGraphiteintercalationcompoundDirectexfoliationofgraphitePreparationmethodsanddiscussionsNaturenanotechnology,vol4,APRIL(2009)DirectexfoliationofgraphiteMicromechanicalexfoliationofgraphite(Scotchtapeorpeel-offmethod).SeebelowvideoDirectexfoliationofgraphiteDispersionsofmicrocrystallinesyn