tantalum surface oxidation bond relaxation, energy entrapment, and electron polarization 2017 yongling guo资料.pdf

该【tantalum surface oxidation bond relaxation, energy entrapment, and electron polarization 2017 yongling guo资料 】是由【小舍儿】上传分享，beplayapp体育下载一共【26】页，该beplayapp体育下载可以免费在线阅读，需要了解更多关于【tantalum surface oxidation bond relaxation, energy entrapment, and electron polarization 2017 yongling guo资料 】的内容，可以使用beplayapp体育下载的站内搜索功能，选择自己适合的beplayapp体育下载，以下文字是截取该文章内的部分文字，如需要获得完整电子版，请下载此beplayapp体育下载到您的设备，方便您编辑和打印。:..AcceptedManuscriptTitle:TantalumSurfaceOxidation:BondRelaxation,EnergyEntrapment,andElectronPolarizationAuthor:YonglingGuoMaolinBoYanWangYonghuiLiuChangQSunYongliHuangPII:S0169-4332(16)32365-0DOI:http://dx./doi:.:APSUSC34312Toappearin:APSUSCReceiveddate:15-7-2016Reviseddate:23-9-2016Accepteddate:1-11-2016Pleasecitethisarticleas:YonglingGuo,MaolinBo,YanWang,YonghuiLiu,ChangQSun,YongliHuang,TantalumSurfaceOxidation:BondRelaxation,EnergyEntrapment,andElectronPolarization,AppliedSurfaceSciencehttp://dx./.,typesetting,andreviewoftheresultingproofbeforeitispublishedinits?,andalllegaldisclaimersthatapplytothejournalpertain.:..TantalumSurfaceOxidation:BondRelaxation,EnergyEntrapment,andElectronPolarizationYonglingGuo,aMaolinBo,bYanWang,cYonghuiLiu,aChangQSun,dYongliHuanga*aKeyLaboratoryofLow-DimensionalMaterialsandApplicationTechnologies(MinistryofEducation),HunanProvincialKeyLaboratoryofThinFilmMaterialsandDevices,FacultyofMaterialsScienceandEngineering,XiangtanUniversity,Hunan411105,ChinabYangtzeNormalUniversity,CollegeofMechanicalandElectricalEngineering,Chongqing408100,ChinacSchoolofInformationandElectronicEngineering,HunanUniversityofScienceandTechnology,Hunan411201,ChinadNOVITAS,SchoolofElectricalandElectronicEngineering,NanyangTechnologicalUniversity,Singapore639798,Singapore*Email:******@:Thebond,electronandenergyrelaxationresultincorelevelenergyshift,localdensification,:..Highlights:?Increasingtheoxygencoveragelowerstheadsorptionenergyassociatedwithlatticereconstruction.?ElectronstransferfromTasurfaceatomstosp-hydratedoxygen,creatingdipolemomentthatdecreasestheworkfunction.?Oxygenchemisorptionmodifiedvalencedensity-of-state(DOS)forTawithfourexcessiveDOSfeatures:O?Tabonding,O2-lonepairs,Ta+electronholes,andthelone-pairpolarizedTadipoles.?Thebond,electronandenergyrelaxationbetweensurfaceundercoordinatedatomsareresponsibleforcorelevelenergyshift,localdensification,-energy-electronrelaxationfortheTa(100,110,111)–Tabonding,lonepairsofoxygen,Ta+electronholes,:oxygengetselectronsfromtwoneighboringTaatomsleftbehindTa+;thesp3-orbitalhybridizationtakesplacewithadditionaltwoelectronlonepairs,-:Ta(100,110,111);oxygenadsorption;DFT–ZPS;entrapment;(Ta)[1]pounds[2]formagroupoffunctionalmaterialsthathavebeenextensively2:..studiedduetotheirtechnologicalapplicationssuchasthinfilmresistorswithlowthermalexpansioncoefficient[3],oxygensensors[4],hardalloys[5,6],erosionandcorrosionresistance[7],andasamaterialofhighdielectricinmetal-oxidesemiconductordevices[8].Besides,Tasurfaceformsanamorphousoxidefilmaftertheoxygenation,onstant[9].Theoxidefilmhasaprotectiveeffectonmetals,whichmakesthetantalumoxidemorewidelyusedinelectronics[10,11],chemicals[12-14],aerospace,weapons,automotiveelectronics,medicalscience[15,16]andscientificresearch[17,18],,Tasurfacesandtantalumoxideshaveattractedmuchattentionwithfocusontheelectronicstructuresofcleanandoxygenadsorptionsurfaces[19-22].Inrecentyears,althoughtheresearchofTaisincreasinglyimportant,themechanismofthedynamicallyelectronicbindingenergyandbondenergyrelaxationatthecleansurfaceoroxidationsurfaceremainsagreatchallenge[23-25].Riffeetetal[26],Guillotetal[27],andWertheimandvanderVeen[28,29]measuredthe4fphotoelectronspectroscopyofcleanTa(100),Ta(110),andTa(111)withandwithoutoxygenadsorptionwithlimitedknowledgeaboutthebondingandelectronicdynamics[30,31].munication,wecorrelatetheadsorptionenergyandworkfunctionwiththeoxygencoveragebasedontheframeworkofdensityfunctionaltheory(DFT)calculations,X-rayphotoelectronspectroscopy(XPS)measurements[32]andbond–order–length–strength(BOLS)consideration[33].Inaddition,wealsoconfirmthepredicteddensityofstate(DOS)featuresofholesandnonbondinglonepairDOSnearthevalencebandedgeofoxygenadsorptionontheTa(100,110,111)surfaceswiththeaidofbond–band–barrier(3B)correlation[33].Resultsconfirmedourpredictionsthatundercoordinationshortensandstiffensthelocalbond,,oxygenadsorptionenhancestheundercoordinationeffectonthebindingenergy(BE):..[33-35]showthatatomicundercoordinationshortensandstrengthenstheremainingbondsbetweenundercoordinatedatoms[33],whichindicatesthatabondlengthbetweenundercoordinatedatoms[36]fromthebulkvaluedbcontractstodz=CzdbandthebondenergyfromthebulkstandardEbincreasestoEz=C?)=dz/db=2/{1+exp[(12?zi)/(8zi)]}isthebondcontractioncoefficientthatrelatedtoziintheithatomiclayerofsurface,andicountsfromtheoutermostatomiclayerinwarduptothethirdlayer(i≤3).TheCz?mistheenergyenhancecoefficientandthebondnatureindexm=1formetals[37].Basedonthetight-binding(TB)theory[38]forthesingle-bodyHamiltonian,H?=22?+Vatom(r)+?2mVcrys(r)(1+?H),-atomicpotentialVatom(r)andtheinvolvementoftheinter-atomicpotentialVcrys(r)withtheeigenwavefunctionattheithatomicsite,vi,,determinesthevthcorelevelenergyofanisolatedatomEv(0)thatfollowsEv(0)=vi,Vatom(r)vi,.Amongthem,vi,satisfiesvivj,,=δijwithδijistheKroneckerfunction(ifi=j,δij=1;otherwise,δij=0).Thez-dependentshiftsdeeperthecorelevel,?Ev(z),followstherelation[34]:zz??????????EzEzEviVrvivjVrvjEvvvz?????0,,,,1?cryscrys???j?1???????(1)Here,theparameter???ν()rVcrys(r)?ν()ristheexchangeintegraland???ν()rVcrys(r)?ν('),?ν(r)(r≠r?)<<,theenergyshift?Ev(z)is4:..proportionaltothecohesiveenergyEzofabondbetweenthez-.(1),anizedas?Ev(z)=Ev(z)?Ev(0)=?Ev(12)(1+?H)=[Ev(12)?Ev(0)]?(1+?H),inwhichperturbation?Hinducedbytheentrapment[39]?=(E?E)/E=C-1?1andpolarization[39]?={[E(p)?E(0)]/[(E(12)?E(0)]}?1=p?(0)andΔEν(12),experimentalconditionsandotherfactors[40].?,wecandeterminethereferentialEv(0)andthezdependentshift?Ev(z)ofthesurfaces:??EzEzEvvv()()(0)orECEzCEzzzvzv??1()()????EEEE(12)(12)(0)???Ezzv(0)()??Cz?zz????????EzEzEEECvvvvvz()()(0)(12)(0)???1(2)WecanobtaintheEv(0)andthecorrespondingbulkshift?Ev(z=12)posingXPSspectrausingconstraintofEq.(2).Besides,wecanalsopredictthez-ohesiveenergy(ECoh(z)/E(12)=(zE)/(zE)=zC-1)andthelocalBEdensity([E(z)/d3]/[E(12)/d3]=C-4)=z/withzb=,,thethermalstabilitydependsonthecohesiveenergy;theelasticityandmechanicalstrengthdependsonthebindingenergydensity;:..–band–barrier(3B)correlationThe3Bcorrelationnotion[33]indicatesthatitisessentialforO,N,andCatomstohybridizetheirsporbitalsuponreactingwithatomsatasolidsurfacetoformquasi-tetrahedronlikeH2O,NH3andCH4,whichdeterminesthecrystallography,morphology,bandstructure,,NH3,andCH4atasolidsurfacewithchemisorbedoxygen,onecanconstructthetetrahedronbondconfiguration,whichistheprimaryoxidequasi-,oxygencatchesanelectronfromitsneighboringBtoformtheO–BbondwithGoldschmidt[41]contractionandelectronholesatthesurface,-orbithybridizationtakesplace,,esadipole,,bondgeometry,valenceDOS,,electronemissionandultrahighelasticity,-selectivephotoelectronspectrometric(ZPS)TheZPS[42]techniqueisabletodistillthecoordination-resolvedelectronicbindingenergyofadatomsoratsitessurroundingsurfaces,interfaces,[43]andspectralareanormalization,theZPSproceedsbysubtractingtheXPSreferencespectrumfromXPSprofiles[32],upontheconstraintconditionsofEq.(2),posedintothedefect(ponent,thesurface(ponentsandthebulk6:..component(B),thistechniquealsocanbeusedtostaticallyanddynamicallymonitorsurfaceprocessessuchascrystalgrowth,defectgeneration,chemicalreaction,alloyformation,,wecalculatethebondcontractionandBEshiftdistributionoftheoptimalTaandadsorptionsurfaceswithfirstprinciples[44,45][46,47]usedtheViennaabinitiosimulationpackagethatbasedontheplane-,wetestedtheexchange-correlationpotentialofthelocaldensityapproximation(LDA)[48]andthegeneralizedgradientapproximation(GGA)[49].paredwiththephotoelectronspectroscopymeasurements,,-pointsgeneratedwitha6×6×(100)surfaceandTa(110)onsistingof3layers,theTa(111)?.TheonebottomlayerwasfixedinthebulkpositionandtheotherTalayerswerefullyrelaxed,,,wealsousedMullikenpopulationanalysis[50]torecordthechargetransfer[51,52]ofundercoordinatedatomsforoxygen-inducedTasurfaces,(DNP)[53]-consistencythresholdofthetotalenergywaswithin10?:..