北京大學(xué)電分析課件液液界面電化學(xué)及電分析化學(xué)簡介

液/液界面電化學(xué)及電 分析化學(xué)簡介邵元華,教授CollegeofChemistryandMolecularEngineering PekingUniversity二00二年十一月液/液界面電化學(xué)及電 分析化學(xué)簡介邵元華,教授Coll11.液/液界面電化學(xué)的發(fā)展歷史2.液/液界面電化學(xué)的基本原理3.液/液界面電化學(xué)的主要研究方法及儀器設(shè)備4.液/液界面電化學(xué)的現(xiàn)狀5.液/液界面電化學(xué)的未來展望主要內(nèi)容1.液/液界面電化學(xué)的發(fā)展歷史主要內(nèi)容2參考書和文獻：1.液/液界面電化學(xué)，P.Vanysek著，羅穎華譯，汪爾康審校，吉林大學(xué)出版社，1987年2.H.H.GiraultandD.J.Schiffrin,inElectroanalyticalChemistry,A.J.Bard.,Ed.;Vol:15,p.1,MarcelDekker,NewYork,19893.H.H.Girault,inModernAspectsofElectrochemistry,J.O.Bockris,B.E.Conway,R.E.White,Eds.;PlenumPress,NewYork,1993,Vol:25,p.14.J.Koryta,Electrochemicalpolarizationphenomenaattheinterfaceoftwoimmiscibleelectrolytesolutions.ElectrochimicaActa,24(1979)293-3005.J.Koryta,Electrochemicalpolarizationphenomenaattheinterfaceoftwoimmiscibleelectrolytesolutions.II.Progresssince1978.ElectrochimicaActa,29(1984)445-4526.VolkovAG,DeamerDW.Liquid-liquidinterfaces.TheoryandMethods.California:CRCPress,1996.參考書和文獻：31.BriefIntroductionofElectrochemistryat Liquid/LiquidInterfaces應(yīng)用電化學(xué)方法研究電荷在液/液界面上的轉(zhuǎn)移反應(yīng)-液/液界面電化學(xué).它是電化學(xué)及電分析化學(xué)的一個重要分支，也是生物電化學(xué)的一個重要組成部分。Charge(electronandion)transferacrossLiquid/Liquid(L/L)interfaces,orOil/Waterinterfaces,ortheinterfacebetweentwoimmiscibleelectrolyteSolutions(ITIES)isoneofthemostfundamentalphysicochemicalprocesses.1.BriefIntroductionofElect4Briefhistory: 1902,NernstandRiesenfeld1906,Cremerpointedoutthattheanalogybetweenthewater/oil/waterconcentrationcellsandbiologicalmembrane1939,VerweyandNiessen,firsttheoreticalpaperontheelectricaldoublelayerandpotentialdistributionatITIES1970s,Gavachetal.inFrance首先認識到L/L界面在一定的實驗條件下可以被極化，并用Chronopotentiometry對一些簡單離子在Water/Nitrobenzene(W/NB)的轉(zhuǎn)移行為進行了研究。同時用ModifiedVerwey-Niessen(MVN)對實驗結(jié)果進行了分析。隨后Korytaetal.發(fā)展了滴水電極及相應(yīng)的實驗裝置，并首先研究了中性載體加速離子轉(zhuǎn)移反應(yīng)。Samecetal.in1979設(shè)計了具有iR降補償性質(zhì)的四電極恒電位儀，用來記錄離子轉(zhuǎn)移反應(yīng)的伏安圖。這樣L/L界面電化學(xué)才在世界各地得到普及和蓬勃發(fā)展。Briefhistory:51980s,汪爾康先生等是中國第一個從事L/L界面電化學(xué)研究的group1986,Giraultetal.第一個將微-L/L界面支持在Micropipettes上 1991,Cornetal.應(yīng)用SHG研究L/L界面 1995，MirkinandBardetal.應(yīng)用SECM研究L/L界面1997,Y.Shaoetal.第一個將納米級-L/L界面支持在Nanopipettes上最近幾年各種光譜技術(shù)也應(yīng)用于此領(lǐng)域的研究1980s,汪爾康先生等是中國第一個從事L/L界面電化學(xué)6WWElectrodeOilGold，Pt，CNB1,2-DCEThedifferencebetweenL/Linterfaceand Electrode/ElectrolyteinterfaceWWElectrodeOilGold，Pt，CNB7Electrochemistryof

L/LinterfacesO+ e=RRedoxReactionsO+ e=RRedoxReactionsMZ(w)=MZ(o)IonTransfertheconventionalElectrochemistryThedifferencebetweenElectrochemistryatL/Linterface andtheconventionalElectrochemistryElectrochemistryofO+ e8ChemicalsensorsElectrochemistryH+，pHK+,Na+,NH4+Cl-,Ac+O+e=RElectroactivespeciesNonelectroactivespeciesL/LInterfaceElectrochemistryatL/LInterfacesisthebridgebetweentheconventionalelectrochemistryandChemicalsensorsChemicalsensorsElectrochemist9ElectrochemistryatLiquid/LiquidInterfacesisafastwaytoselectreceptorsformakingchemicalsensorsElectrochemistryatLiquid/10ElectrodeOBiologicalMembraneModelL/LInterfaceElectrode/electrolyte

Membrane/solutionArtificial,supportedmembraneandBLMElectrodeOBiologicalMembrane11ElectrochemistryatL/LInterfacesNewBranchofElectrochemistryMechanismofChemicalsensorsPhaseTransfercatalyticreactionsMimickingbiologicalmembranesResearchSignificanceandapplicationsofElectrochemistryatL/LInterfacesExtractionMechanismElectrochemistryNewBranchofM122.液/液界面電化學(xué)的基本原理2.1.EquilibriumconditionsandNernstpotentialIngeneralatLiquid/Liquidinterfaces,therearetwotypesofchargepartition: (A)thetransferofanionMwiththechargenumberzfromthephasewtothephaseoandthereverse: MZ(w) =MZ(o)M+(w) +L(o) =ML+(o)(B)theelectrontransferbetweenaredoxcoupleO1/R1inthephasewandaredoxcoupleO2/R2inthephaseo,whichcanberepresentedas:O1(w)+R2(o)=R1(w)+O2(o)

2.液/液界面電化學(xué)的基本原理2.1.Equilibrium13NernstEquationsNernstEquations14Liquid/Liquidinterfaceshavebeenclassifiedintotheideal-polarizedinterfaceandno-polarizedinterface.2.2.SingleionGibbsenergyoftransferTATBassumptionLiquid/Liquidinterfaceshave15北京大學(xué)電分析課件液液界面電化學(xué)及電分析化學(xué)簡介162.3.SolvationofIonBornequation2.4.Interfacialstructureandtheiontransfermechanism(A)MVNMODEL(B)GSMODEL2.3.SolvationofIon2.4.Interf17北京大學(xué)電分析課件液液界面電化學(xué)及電分析化學(xué)簡介18北京大學(xué)電分析課件液液界面電化學(xué)及電分析化學(xué)簡介192.5.SolventsandbaseelectrolytesThereareover20organicsolventswhichhavebeentestedintheITIESstudiessofar.AspointedoutbyKorytaet.al.,thefollowingthreerequirementshavebeencommonlyusedtochoosetheorganicsolvent:(1).Thesolubilityofsolventinwaterandwaterinthesolventmustbeverysmall.(2).Thesolventmustbesufficientlypolartopromotesufficientdissociationofthesupportingelectrolyteandthuskeepingenoughconductivityofthesolution.(3).Thedensityofthesolventshoulddiffersignificantlyfromthatofaqueousphaseinordertogetaphysicallystablel/linterface.2.5.Solventsandbaseelectrol20Atpresent,themostcommonlyusedorganicsolventsarenitrobenzene(NB)and1,2-dichloroethane(1,2-DCE).Someothersolventshavebeentriedinthepasttwodecades,forexample,propiophenone,4-isopropyl-1-methyl-2-nitrobenzene,dichloro-methane,nitrotulene,chloroform,anilineetc.Inordertogetmoreflexiblechoice,organicsolventmixtureshavebeenalsoemployed,forexample,nitrobenzene+chlorobenzene,NB+benzonitrileandNB+benzene.Baseelectrolytes:TBATPB(tetrabutylammoniumtetraphenylborate),TBATPBCl,CVTPB,BTPPATPB(Bis[triphenylphosphoranylidene]ammoniumtetraphenylborate)Atpresent,themostcommonly21北京大學(xué)電分析課件液液界面電化學(xué)及電分析化學(xué)簡介22北京大學(xué)電分析課件液液界面電化學(xué)及電分析化學(xué)簡介233.液/液界面電化學(xué)的主要研究方法 及儀器設(shè)備Almostalltheinstrumentshavebeenusedtostudyclassicalelectrochemistrycanbeusedtoinvestigatethechargetransferatliquid/Liquidinterfaces.4-electrodepotentiostat--------BigiRdropaqueoussolutiondropping(ascending)electrodetwo-electrodesystem--------microelectrodesRecently,wedevelopedanoveltechniquetostudyITIESwiththree-electrodesetupwiththehelpofthephaseratio.Thus,allelectrochemicallabscandoresearchonthissubjects.3.液/液界面電化學(xué)的主要研究方法Almostallth24北京大學(xué)電分析課件液液界面電化學(xué)及電分析化學(xué)簡介252-電極系統(tǒng)2-電極系統(tǒng)26應(yīng)用于液/液界面電化學(xué)研究的升水電極-四電極系統(tǒng)應(yīng)用于液/液界面電化學(xué)研究的27北京大學(xué)電分析課件液液界面電化學(xué)及電分析化學(xué)簡介28北京大學(xué)電分析課件液液界面電化學(xué)及電分析化學(xué)簡介29新的技術(shù)，例如:SHG(Secondharmonicgeneration)microelectrodes,micropipettesandnano-pipettesSECMFemto-laserSimulationsThinfilms現(xiàn)已用在L/LInterfaces的研究。各種電化學(xué)方法和技術(shù)新的技術(shù)，例如:各種電化學(xué)方法和技術(shù)304.液/液界面電化學(xué)的現(xiàn)狀Structure: MVNModelandGSModelMechanism: FacilitatediontransfermechanismKinetics: Butler-Volmerequation,Marcustheory Nanometeropipettes SECMApplications:

Thinfilms(solarcell,drugdelivery)4.液/液界面電化學(xué)的現(xiàn)狀31目前國際上液/液界面電化學(xué)研究 存在的主要問題1.界面結(jié)構(gòu)未知!MVN模型和混合溶劑層模型(GS)2.可供選擇作為有機相的有機溶劑數(shù)目有限3.沒有很好的獲取轉(zhuǎn)移反應(yīng)動力學(xué)的實驗手段4.iR(i-電流，R-電阻，iR降是由于溶液中電阻所引起的干擾)降及充電電流較常規(guī)電化學(xué)更加嚴重目前國際上液/液界面電化學(xué)研究1.界面結(jié)構(gòu)未知!MVN32HowtosolvetheseProblemsMicroelectrodes:SolidandNano-andMicropipettes+ScanningElectrochemicalMicroscopy,SECMHowtosolvetheseProblemsMic33ElectrochemistryatL/LInterfacesArtificialMembrane/ElectrolyteInterfacesBLMArtificialMembraneandBiosensorsModifiedL/LInterfacesMicroelectrodesNano-andMicropipettesSECMElectrochemistryArtificialMe34TheSEMdiagramsofNano-andMicropipettesMicropipettesNanopipettesTheSEMdiagramsofMicropipett35MicropipettesTheta()MicropipetteMicropipettesTheta()Micropip36TheSEMdiagramsofNano-andMicropipettesMicropipettesNanopipettes我們group可以制備內(nèi)徑從幾個nm到十幾個m的玻璃納、微米管TheSEMdiagramsofMicropipett37AqueousPhaseOrganicPhaseAqueousPhaseOrganicPhaseAsymmetricDiffusionFieldAqueousPhaseOrganicPhaseAque38TBATPBassupportingelectrolyteinDCETBATPBClassupportingelectrolyteinDCEBTPPATPBassupportingelectrolyteinDCEMicropipetteasatooltodeterminetheionicspecieslimitingthepotentialwindowatL/LInterfacesTBATPB(Tetrabutyalammoniumtetraphenylborate)TBATPBCl(tetrabutyl-ammoniumtetrakis[4-chlorophenyl]borate)BTPPATPB(Bis[triphosphor-anylidene]ammoniumtetraphenyl-borate)1,2-dichloroethane(DCE)TBATPBassupportingTBATPBCl39Ag/AgCl/0.01MTBACl/0.25mMDB18C6+0.01MTBATPBCl//0.01MKCl/AgCl/AgIdentifythedifferentmechanismsAg/AgCl/0.01MTBACl/0.25mMDB18C40ACTTOCTICTIDwowowowoIdentifyofdifferentmechanismsoffacilitatediontransfersACTTOCTICTIDwowowowoIdentifyo41北京大學(xué)電分析課件液液界面電化學(xué)及電分析化學(xué)簡介42Idisk=4nFaDCIpip=3.35nFaDCWhyIpipisabout2.63timesbiggerthanIdisk?Silanizationplaysveryimportantrolehere!Anal.Chem.,1998,70,p3155-3161Idisk=4nFaDCIpip=3.35nFaDCW433.4E-93.4E-944北京大學(xué)電分析課件液液界面電化學(xué)及電分析化學(xué)簡介45Nanometer-sizedL/LInterface納米管NanopipetAqueousPhaseNanometer-sized納米管Aqueous46Nano-ITIESkofrom0.1cm/sto10cm/sA54nmradiusB5nmradiusJ.Am.Chem.Soc.,1997,119,8103K+(w)+DB18C6(DCE)=[K+DB18C6](DCE)

Nano-ITIESJ.Am.Chem.Soc.,199747北京大學(xué)電分析課件液液界面電化學(xué)及電分析化學(xué)簡介48J.Am.Chem.Soc.,1998,120,12700科學(xué)意義和創(chuàng)新點：第一次在實驗上實現(xiàn)了非氧化還原物質(zhì)的Generation/CollectionMode。對于測量反應(yīng)中間產(chǎn)物和快速電荷轉(zhuǎn)移反應(yīng)動力學(xué)有重要意義。J.Am.Chem.Soc.,1998,120,12749北京大學(xué)電分析課件液液界面電化學(xué)及電分析化學(xué)簡介50Thephotoof-micropipetteundermicroscopeThephotoof-micropipetteun51北京大學(xué)電分析課件液液界面電化學(xué)及電分析化學(xué)簡介52“Non-solution”L/LInterfaceElectrochemistry“Non-solution”L/LInterface53Generator(1)andcollector(2)voltammogramsofthetransferofK+betweenwaterandDCEcontainingDB18C6igvs.Egandicvs.Egcurvesobtainedwithanaqueousfilmlinkingtwobarrelsofthe-pipetGenerator(1)andcollectorig54Detectionofammoniaintheair.Cyclicvoltammogamsobtainedwitha-pipetexposedtoair(1)andammoniavaporaboveits2MsolutionDetectionofammoniaintheai55ThepotentialwindowsdependupontheamountofAgar.Scanrateis30mV/s.Theradiusofthemicropipetteis4m，curves1、2、3and4correspondingto25%、10%、1%and0.5%ofAgar,respectivelyAgar-waterMicroelectrodeThepotentialwindowsdependu56CyclicVoltammogramsofK+transferfacilitatedbyDB18C6.KClis0.1M，Scanrate=30mV/s。Theradiusofthemicropipetteis3μm。Curves1,2and3correspondingtotheconcentrationsofDB18C60.25,0.5and1.0mM.123CyclicVoltammogramsofK+tra57(a)r=12μm(b)r=3μm.(a)r=12μm(b)r=3μm.58Planarstructure(a)and3Dstructure(b)ofanewtypeofcrownetherCyclicvoltammogramwithscanrateof10mV/sfora14m-radiusmicropipetteelectrodewith100mMNaClinaqueousphaseand10mMTBATPBinorganicphasePlanarstructure(a)and3DCy59Alkalimetalionstransferacrossthewater/DCEinterfaceFacilitatedbyDB18C6Alkalimetalionstransferacr60Ionradius(r),formaltransferpotentialofrelevantalkalimetalionsandtheassociationconstantsofcomplex(M-DB18C6)+inDCEphaseIonradius(r),formaltransfe61冰/有機相溶液界面研究示意圖冰/有機相溶液界面研究示意圖62應(yīng)用常規(guī)三電極裝置(恒電位儀)研究電荷在液/液界 面上的轉(zhuǎn)移反應(yīng)實驗裝置圖Aqueousphase應(yīng)用常規(guī)三電極裝置(恒電位儀)研究電荷在液/液界Aqueou63異相電子轉(zhuǎn)移反應(yīng)創(chuàng)新點：用四(二)電極系統(tǒng)所能研究的體系，如離子、加速離子和電子轉(zhuǎn)移反應(yīng)，均能用常規(guī)三電極系統(tǒng)進行研究，這對于普及和發(fā)展此領(lǐng)域有重要意義。異相電子轉(zhuǎn)移反應(yīng)創(chuàng)新點：用四(二)64Ag/AgClAg/AgCl655.液/液界面電化學(xué)的未來展望InterfacialstructureApplicationsBiologicalMembranesKineticsandPhaseTransferCatalysisSolarcellsDrugDeliveryandpharmacokinetics5.液/液界面電化學(xué)的未來展望66液/液界面電化學(xué)及電 分析化學(xué)簡介邵元華,教授CollegeofChemistryandMolecularEngineering PekingUniversity二00二年十一月液/液界面電化學(xué)及電 分析化學(xué)簡介邵元華,教授Coll671.液/液界面電化學(xué)的發(fā)展歷史2.液/液界面電化學(xué)的基本原理3.液/液界面電化學(xué)的主要研究方法及儀器設(shè)備4.液/液界面電化學(xué)的現(xiàn)狀5.液/液界面電化學(xué)的未來展望主要內(nèi)容1.液/液界面電化學(xué)的發(fā)展歷史主要內(nèi)容68參考書和文獻：1.液/液界面電化學(xué)，P.Vanysek著，羅穎華譯，汪爾康審校，吉林大學(xué)出版社，1987年2.H.H.GiraultandD.J.Schiffrin,inElectroanalyticalChemistry,A.J.Bard.,Ed.;Vol:15,p.1,MarcelDekker,NewYork,19893.H.H.Girault,inModernAspectsofElectrochemistry,J.O.Bockris,B.E.Conway,R.E.White,Eds.;PlenumPress,NewYork,1993,Vol:25,p.14.J.Koryta,Electrochemicalpolarizationphenomenaattheinterfaceoftwoimmiscibleelectrolytesolutions.ElectrochimicaActa,24(1979)293-3005.J.Koryta,Electrochemicalpolarizationphenomenaattheinterfaceoftwoimmiscibleelectrolytesolutions.II.Progresssince1978.ElectrochimicaActa,29(1984)445-4526.VolkovAG,DeamerDW.Liquid-liquidinterfaces.TheoryandMethods.California:CRCPress,1996.參考書和文獻：691.BriefIntroductionofElectrochemistryat Liquid/LiquidInterfaces應(yīng)用電化學(xué)方法研究電荷在液/液界面上的轉(zhuǎn)移反應(yīng)-液/液界面電化學(xué).它是電化學(xué)及電分析化學(xué)的一個重要分支，也是生物電化學(xué)的一個重要組成部分。Charge(electronandion)transferacrossLiquid/Liquid(L/L)interfaces,orOil/Waterinterfaces,ortheinterfacebetweentwoimmiscibleelectrolyteSolutions(ITIES)isoneofthemostfundamentalphysicochemicalprocesses.1.BriefIntroductionofElect70Briefhistory: 1902,NernstandRiesenfeld1906,Cremerpointedoutthattheanalogybetweenthewater/oil/waterconcentrationcellsandbiologicalmembrane1939,VerweyandNiessen,firsttheoreticalpaperontheelectricaldoublelayerandpotentialdistributionatITIES1970s,Gavachetal.inFrance首先認識到L/L界面在一定的實驗條件下可以被極化，并用Chronopotentiometry對一些簡單離子在Water/Nitrobenzene(W/NB)的轉(zhuǎn)移行為進行了研究。同時用ModifiedVerwey-Niessen(MVN)對實驗結(jié)果進行了分析。隨后Korytaetal.發(fā)展了滴水電極及相應(yīng)的實驗裝置，并首先研究了中性載體加速離子轉(zhuǎn)移反應(yīng)。Samecetal.in1979設(shè)計了具有iR降補償性質(zhì)的四電極恒電位儀，用來記錄離子轉(zhuǎn)移反應(yīng)的伏安圖。這樣L/L界面電化學(xué)才在世界各地得到普及和蓬勃發(fā)展。Briefhistory:711980s,汪爾康先生等是中國第一個從事L/L界面電化學(xué)研究的group1986,Giraultetal.第一個將微-L/L界面支持在Micropipettes上 1991,Cornetal.應(yīng)用SHG研究L/L界面 1995，MirkinandBardetal.應(yīng)用SECM研究L/L界面1997,Y.Shaoetal.第一個將納米級-L/L界面支持在Nanopipettes上最近幾年各種光譜技術(shù)也應(yīng)用于此領(lǐng)域的研究1980s,汪爾康先生等是中國第一個從事L/L界面電化學(xué)72WWElectrodeOilGold，Pt，CNB1,2-DCEThedifferencebetweenL/Linterfaceand Electrode/ElectrolyteinterfaceWWElectrodeOilGold，Pt，CNB73Electrochemistryof

L/LinterfacesO+ e=RRedoxReactionsO+ e=RRedoxReactionsMZ(w)=MZ(o)IonTransfertheconventionalElectrochemistryThedifferencebetweenElectrochemistryatL/Linterface andtheconventionalElectrochemistryElectrochemistryofO+ e74ChemicalsensorsElectrochemistryH+，pHK+,Na+,NH4+Cl-,Ac+O+e=RElectroactivespeciesNonelectroactivespeciesL/LInterfaceElectrochemistryatL/LInterfacesisthebridgebetweentheconventionalelectrochemistryandChemicalsensorsChemicalsensorsElectrochemist75ElectrochemistryatLiquid/LiquidInterfacesisafastwaytoselectreceptorsformakingchemicalsensorsElectrochemistryatLiquid/76ElectrodeOBiologicalMembraneModelL/LInterfaceElectrode/electrolyte

Membrane/solutionArtificial,supportedmembraneandBLMElectrodeOBiologicalMembrane77ElectrochemistryatL/LInterfacesNewBranchofElectrochemistryMechanismofChemicalsensorsPhaseTransfercatalyticreactionsMimickingbiologicalmembranesResearchSignificanceandapplicationsofElectrochemistryatL/LInterfacesExtractionMechanismElectrochemistryNewBranchofM782.液/液界面電化學(xué)的基本原理2.1.EquilibriumconditionsandNernstpotentialIngeneralatLiquid/Liquidinterfaces,therearetwotypesofchargepartition: (A)thetransferofanionMwiththechargenumberzfromthephasewtothephaseoandthereverse: MZ(w) =MZ(o)M+(w) +L(o) =ML+(o)(B)theelectrontransferbetweenaredoxcoupleO1/R1inthephasewandaredoxcoupleO2/R2inthephaseo,whichcanberepresentedas:O1(w)+R2(o)=R1(w)+O2(o)

2.液/液界面電化學(xué)的基本原理2.1.Equilibrium79NernstEquationsNernstEquations80Liquid/Liquidinterfaceshavebeenclassifiedintotheideal-polarizedinterfaceandno-polarizedinterface.2.2.SingleionGibbsenergyoftransferTATBassumptionLiquid/Liquidinterfaceshave81北京大學(xué)電分析課件液液界面電化學(xué)及電分析化學(xué)簡介822.3.SolvationofIonBornequation2.4.Interfacialstructureandtheiontransfermechanism(A)MVNMODEL(B)GSMODEL2.3.SolvationofIon2.4.Interf83北京大學(xué)電分析課件液液界面電化學(xué)及電分析化學(xué)簡介84北京大學(xué)電分析課件液液界面電化學(xué)及電分析化學(xué)簡介852.5.SolventsandbaseelectrolytesThereareover20organicsolventswhichhavebeentestedintheITIESstudiessofar.AspointedoutbyKorytaet.al.,thefollowingthreerequirementshavebeencommonlyusedtochoosetheorganicsolvent:(1).Thesolubilityofsolventinwaterandwaterinthesolventmustbeverysmall.(2).Thesolventmustbesufficientlypolartopromotesufficientdissociationofthesupportingelectrolyteandthuskeepingenoughconductivityofthesolution.(3).Thedensityofthesolventshoulddiffersignificantlyfromthatofaqueousphaseinordertogetaphysicallystablel/linterface.2.5.Solventsandbaseelectrol86Atpresent,themostcommonlyusedorganicsolventsarenitrobenzene(NB)and1,2-dichloroethane(1,2-DCE).Someothersolventshavebeentriedinthepasttwodecades,forexample,propiophenone,4-isopropyl-1-methyl-2-nitrobenzene,dichloro-methane,nitrotulene,chloroform,anilineetc.Inordertogetmoreflexiblechoice,organicsolventmixtureshavebeenalsoemployed,forexample,nitrobenzene+chlorobenzene,NB+benzonitrileandNB+benzene.Baseelectrolytes:TBATPB(tetrabutylammoniumtetraphenylborate),TBATPBCl,CVTPB,BTPPATPB(Bis[triphenylphosphoranylidene]ammoniumtetraphenylborate)Atpresent,themostcommonly87北京大學(xué)電分析課件液液界面電化學(xué)及電分析化學(xué)簡介88北京大學(xué)電分析課件液液界面電化學(xué)及電分析化學(xué)簡介893.液/液界面電化學(xué)的主要研究方法 及儀器設(shè)備Almostalltheinstrumentshavebeenusedtostudyclassicalelectrochemistrycanbeusedtoinvestigatethechargetransferatliquid/Liquidinterfaces.4-electrodepotentiostat--------BigiRdropaqueoussolutiondropping(ascending)electrodetwo-electrodesystem--------microelectrodesRecently,wedevelopedanoveltechniquetostudyITIESwiththree-electrodesetupwiththehelpofthephaseratio.Thus,allelectrochemicallabscandoresearchonthissubjects.3.液/液界面電化學(xué)的主要研究方法Almostallth90北京大學(xué)電分析課件液液界面電化學(xué)及電分析化學(xué)簡介912-電極系統(tǒng)2-電極系統(tǒng)92應(yīng)用于液/液界面電化學(xué)研究的升水電極-四電極系統(tǒng)應(yīng)用于液/液界面電化學(xué)研究的93北京大學(xué)電分析課件液液界面電化學(xué)及電分析化學(xué)簡介94北京大學(xué)電分析課件液液界面電化學(xué)及電分析化學(xué)簡介95新的技術(shù)，例如:SHG(Secondharmonicgeneration)microelectrodes,micropipettesandnano-pipettesSECMFemto-laserSimulationsThinfilms現(xiàn)已用在L/LInterfaces的研究。各種電化學(xué)方法和技術(shù)新的技術(shù)，例如:各種電化學(xué)方法和技術(shù)964.液/液界面電化學(xué)的現(xiàn)狀Structure: MVNModelandGSModelMechanism: FacilitatediontransfermechanismKinetics: Butler-Volmerequation,Marcustheory Nanometeropipettes SECMApplications:

Thinfilms(solarcell,drugdelivery)4.液/液界面電化學(xué)的現(xiàn)狀97目前國際上液/液界面電化學(xué)研究 存在的主要問題1.界面結(jié)構(gòu)未知!MVN模型和混合溶劑層模型(GS)2.可供選擇作為有機相的有機溶劑數(shù)目有限3.沒有很好的獲取轉(zhuǎn)移反應(yīng)動力學(xué)的實驗手段4.iR(i-電流，R-電阻，iR降是由于溶液中電阻所引起的干擾)降及充電電流較常規(guī)電化學(xué)更加嚴重目前國際上液/液界面電化學(xué)研究1.界面結(jié)構(gòu)未知!MVN98HowtosolvetheseProblemsMicroelectrodes:SolidandNano-andMicropipettes+ScanningElectrochemicalMicroscopy,SECMHowtosolvetheseProblemsMic99ElectrochemistryatL/LInterfacesArtificialMembrane/ElectrolyteInterfacesBLMArtificialMembraneandBiosensorsModifiedL/LInterfacesMicroelectrodesNano-andMicropipettesSECMElectrochemistryArtificialMe100TheSEMdiagramsofNano-andMicropipettesMicropipettesNanopipettesTheSEMdiagramsofMicropipett101MicropipettesTheta()MicropipetteMicropipettesTheta()Micropip102TheSEMdiagramsofNano-andMicropipettesMicropipettesNanopipettes我們group可以制備內(nèi)徑從幾個nm到十幾個m的玻璃納、微米管TheSEMdiagramsofMicropipett103AqueousPhaseOrganicPhaseAqueousPhaseOrganicPhaseAsymmetricDiffusionFieldAqueousPhaseOrganicPhaseAque104TBATPBassupportingelectrolyteinDCETBATPBClassupportingelectrolyteinDCEBTPPATPBassupportingelectrolyteinDCEMicropipetteasatooltodeterminetheionicspecieslimitingthepotentialwindowatL/LInterfacesTBATPB(Tetrabutyalammoniumtetraphenylborate)TBATPBCl(tetrabutyl-ammoniumtetrakis[4-chlorophenyl]borate)BTPPATPB(Bis[triphosphor-anylidene]ammoniumtetraphenyl-borate)1,2-dichloroethane(DCE)TBATPBassupportingTBATPBCl105Ag/AgCl/0.01MTBACl/0.25mMDB18C6+0.01MTBATPBCl//0.01MKCl/AgCl/AgIdentifythedifferentmechanismsAg/AgCl/0.01MTBACl/0.25mMDB18C106ACTTOCTICTIDwowowowoIdentifyofdifferentmechanismsoffacilitatediontransfersACTTOCTICTIDwowowowoIdentifyo107北京大學(xué)電分析課件液液界面電化學(xué)及電分析化學(xué)簡介108Idisk=4nFaDCIpip=3.35nFaDCWhyIpipisabout2.63timesbiggerthanIdisk?Silanizationplaysveryimportantrolehere!Anal.Chem.,1998,70,p3155-3161Idisk=4nFaDCIpip=3.35nFaDCW1093.4E-93.4E-9110北京大學(xué)電分析課件液液界面電化學(xué)及電分析化學(xué)簡介111Nanometer-sizedL/LInterface納米管NanopipetAqueousPhaseNanometer-sized納米管Aqueous112Nano-ITIESkofrom0.1cm/sto10cm/sA54nmradiusB5nmradiusJ.Am.Chem.Soc.,1997,119,8103K+(w)+DB18C6(DCE)=[K+DB18C6](DCE)

Nano-ITIESJ.Am.Chem.Soc.,1997113北京大學(xué)電分析課