xps eng电子能谱是60年代末和70初才发展起来的一种研究表面新

PhotoelectronXPS:X-rayPhotoelectronAES:AugerElectronUPS:UltravioletPhotoelectronSpectroscopyXPS,alsoknownasESCA(ElectronSpectro-scopyforChemical ysis),isthemostwidelyusedsurface ysistechniquebecauseofitsrelativesimplicityinuseanddata一定量的电子，X射线或紫外中不同能级的电子激发成自由息，并具有特征能量，收集这Acertainamountofelectrons,X-sample,thanthesamplesurfaceelectronscanbeexcitedintothetheinformationofthesamplesenergy,collectingtheseexcitedWhatis–X-rayPhotoelectronspectroscopy,basedonthephotoelectriceffect,1,2wasdevelopedinthemid-1960’sbyKaiSiegbahnandhisresearchgroupattheUniversityofUppsala,1.H.Hertz,Ann.Physik31,9832.A.Einstein,Ann.Physik17,132(1905).1921NobelPrizein3.K.Siegbahn,et.al.,NovaActaRegiaeSoc.Sci.,Ser.IV,Vol.20NobelPrizeinPhysicsPrinciplesofXPSBasedonphotoelectriceffect收的光子的能量大于电子的结合能及样品的功函数，该电子可以逃逸出品表面，跑到真空中，并且还具有一定的动能，这就是光电效应ThePhotoelectricIt'sbeendeterminedexperimentallythatwhenlightshinesonametalsurface,thesurfaceemitselectrons.Forexample,youcanstartacurrentinacircuitjustbyshiningalightonametal te.Whydoyouthinkthishappens? Ifawaveoflighthitanelectroninoneoftheatomsinthemetal,itmighttransferenoughenergytoknockthe 光电效具有足够能量的入射光子（h）同样品相互作用时， ThePhotoelectricCorelevelelectronsareejectedbytheX-rayradiationTheK.E.oftheemittedelectronsisdependenton:InstrumentworkElementbinding

KineticKE=hν-(EB+EB=ElectronBindingKE=ElectronKineticΦspec=SpectrometerWorkXPSIntensitiesofphotoelectronsversus析 移（Chemical化 现可以利用原子的静电模型（tticl。内电子主要感受到原子核的仑力，使电子在原子内具合，同时内层电子又受到外电子的 作用（推斥力ExampleofChemicalFunctionsofElementalidentificationandchemicalstateofRelativecompositionoftheconstituentsinthesurfaceregionValencebandElectron X-rayArionElectronicComputerVacuumUltrahighvacuumsystem<10-9Torr(<10-7DetectionofAvoidsurfaceXPSspectrallinesareidentifiedbythefromwhichtheelectronwasejected(1s,2s,2p,Forp,dandfpeaks,twopeaksare–Theseparationbetweenthetwopeaksarenamed

rbitalsplitting.Thevaluesofspinorbitalsplittingofacorelevelofanelementindifferentcompoundsarenearlythesame.–Thepeakarearatiosofacorelevelofanelementindifferentcompoundsarealsonearlythesame.层激发出来的分别计为2s,2p½,2p3/2光电子，以此类推M层和N层都有光电子产生。其中Ag3d3/2和Ag3d5/2光电子是Ag的两个最强特征峰 XPSspectrumofaNiXPSinExceptHandHe,allotherelementshavecharacteristicXPSandAESpeaksThesepeakshardlyoverlappedoneChemicalshift→oxidationThus,XPScanbeusedtoidentifytheelementanditsoxidationstate X－射线光电子能谱在催化研究中的应组分鉴别（identificationof价态分(oxidation半定量分析 SensitivityNanocastedsynthesisofmesoporousperovskiteNanostructuredceria/bariumT10=400,T50=540,T90=690

Citrate

T10=335°CT50=470°CT90=550 a:MesoporousCr2O BindingRestructuringTransitionMetalOxideNanorodsfor100%SelectivityinReductionofNitricOxidewithCarbonMonoxideNanoLett.2013,13,CO+H2O=J.Am.Chem.Soc.2013,135,Ag-TiO2/KIT-6复合纳米光 N2物理吸附、XPS、UV-VisDRS和TEM对系列催化剂进行表征，结果A-.图3为各催化剂的Uv-VisDRS谱。负载Ag与未负载(4O0～6OOnm)出现强的吸收峰，这归属为单质si，O和C五种元素存在。图4是Ag3d，Ti2p的分析图谱。如图4(b)所示，两样品的XPS谱均在458.7和464.2eV左右出现两个峰，它们对应于TiO2(Ti4+