electron-电子显微镜的电子光学基础

ElectronTransmissionElectronMicroscopyScanningElectronMicroscopyTopography:surfacefeatures,texture→hardness，reflectivity...Morphology:shapeandsizeofparticles→strength，Composition:qualitative In-situTransmissionelectronmicroscopyElectro-opticalfoundationofEM电子显微镜的电子光学基础Resolution（分辨率）referstotheabilitytoclearlyidentifytheobjectdetailskills(分辨率是指能够清晰地辨认物体细节的本领)。δδ=0.61λ/n· VolatilityofVolatilityofelectronsandwavelength(电子的波动性及电式中 根据能量守恒原理(principleofconservationofenergy)，电子获得的动能为： e

电子加速电(1-1-3代入1-1

(1-式中 电子的静止质量 光Thehigherthevoltage,theshorterthewavelength,thehighertheElectronicparticulateandrefractionlaw(电子的微粒性与折condenserlens+

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TransmissionelectronApplicationofNucleiorcrystallitestructureinearlyofgrowth StructuraldefectsStudiesof Shapeandsizeofnanocrystals纳米晶形状和尺度的研CharacterizationofMesostructures..Barium

一、Growth一、GrowthAmphiphilic

JACS,2003,125(12):3450-二、Particleshapesizeand二、Particleshapesizeand1Au1Au、particlesizesFrequencyFrequency

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dispersionona2,6nm01.01.52.02.53.03.54.05.05.56,01618SupporteffectsintheAu-catalyzedCO J.Catal.RepresentativeTEMimagesandparticlesizedistributionofAuofthefourdifferentlysupportedAucatalystsaftercalcinationin10%O2/N2at250 Cfor2h.OxygenvacancyBulkystructureoffold8-foldfoldLiHY,WangHF,GongXQ,LuGZ,etalPhysicalReviewB79,193401(2009) O1 34

O 2electronsCe4+beingreducedto 234

VVVVTwoCe3+werealllocatedatsecond-nearestatomsSub-surfaceO

Evac=2.13 Evac=1.95Thelocalizationof4felectroninCeO2determinedthemoststablestatearetwoelectronsatthesecond-nearestatoms.SurfaceOvacancy

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Evac=1.95BothGeometric&ElectronicpropertiesofCeO2determinedthelocalizationstateofelectronsaroundOvacancy.SurfacechemistryofEad=~0.72.Catalystofdirectmethanol2.GlycolusedassolventaswellasreductingagentathighChem.Near-infrared(NIR)-emittingquantumdots(QDs)havebeenhamperedbytheirinstabilityandlowphotoluminescence(PL)efficiencies.Here,water-solublehighlyluminescentNIR-emittingQDsweredevelopedthroughconstructingCdTe/CdSe/ZnScore/s nanostructure.ByvaryingthesizeofCdTecoresandthethicknessoftheCdSes ,theemissionwavelengthoftheobtainednanostructurecanspanfrom540to825nm.Inaddition,thepassivationoftheZnSs withasubstantiallywidebandgapconfinestheexcitonswithintheCdTe/CdSeinterfaceandisolatesthemfromthesolutionenvironmentandconsequentlyimprovesthestabilityofthenanostructure,especiallyinaqueousmedia.NormalizedUV−visspectra(A)andPLspectra(λex=400nm)ofCdTecoreswithadiameterof2.6nm(a)andCdTe/CdSecore/s QDsstartingfromtheCdTecoresbutwithdifferentMLsofCdSes :(b)one,(c)two,(d)three,and(e)four.Forspectrumf,theCdTecorediameteris3.0nmandtheCdSes thicknessamountstofourMLs.SolarCuInS2/ZnS(CIS-Z)Core/S quantumdots structureofFe3O4@AuAuCO5.5.Auseedsinducedanisotropygrowthof6.Low6.LowtemperatureoxidationCOoverCo3O4Nature,2009,458(7239),746- 7.7.RareearthAngew.Chem.,2005.117:3320-Cheapresources,Diphenyletheras了了Urea,Liang-ShuZhong,Chem.Mater.,2007.19:1648-Glucose/Acrylic8.8.Rareearthfluoridefluorescent9.9.MorphologycontrolodsemiconductorsandmetalAngew.Chem.Int.Ed.2006,45,ChemSocRev:2014,43,: 三.三. ctionofmetalwithEvolutionofmetal-support ctioneffects,asrevealedbyHRTEM:decorationofmetalPt-Cereversibilityofmetal-supportdecorationeffectsRedispersionofRhintosmall,surface-clean,particlesafteroxidationatahightemperatureof1173K(right).四、EDAX四、EDAXbabagpgpElementTEM&Element6346 17 34Charge

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