电化学工作站(简易说明)

Chapter4.SetupMenu

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TechniqueCommand

Usethiscommandtoselectanelectrochemicaltechnique.

ThiscommandpresentsanElectrochemicalTechniquesdialogbox:

Thefollowingoptionsallowyoutoselectanelectrochemicaltechnique:

TechniqueSelection

Selecttheelectrochemicaltechniqueyouwanttouse.Thisboxliststhetechniques

availableintheinstrument.Doubleclickingthetechniqueyouwanttoselectisequivalentto

selectingthetechniqueandclickingtheOKbutton.

PolarographicMode

Checkthisboxwillenablethepolarographicmode.Inthepolarographicmode,the

mercurydropwillbeallowedtogrowandbedislodgedforeverydatapoint.

Onlyafewtechniquesareallowedtohavepolarographicmode:SamplingCurrent

(Staircase)Polarography(SCP),DifferentialPulsePolarography(DPP),NormalPulse

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Chapter4.SetupMenu

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Polarography(NPP),DifferentialNormalPulsePolarography(DNPP),A.C.Polarography

(ACP),andSecondHarmonicA.C.Polarography(SHACP).

Oncepolarographicmodeisenabled,strippingmodeisdisabled.Inordertosetstripping

modebyusingtheStrippingModecommandinControlMenu,youhavetouncheckthe

polarographicmode.

Thiscommandhasatoolbarbutton:

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Chapter4.SetupMenu

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ParametersCommand

Usethiscommandtosetexperimentalparameters.

ThiscommandpresentsaParameterdialogboxsoyoucanselecttheparametersyou

wanttouse.

Dependingonthetechnique,theparametersdialogboxwillbedifferent.Thefollowings

aretheparametersfordifferenttechniques:

ParametersforCyclicVoltammetry

ParametersforLinearSweepVoltammetry

ParametersforSampledCurrentVoltammetry

ParametersforTafelPlot

ParametersforChronoamperometry

ParametersforChronocoulometry

ParametersforDifferentialPulseVoltammetry

ParametersforNormalPulseVoltammetry

ParametersforDifferentialNormalPulseVoltammetry

ParametersforSquareWaveVoltammetry

ParametersforA.C.Voltammetry

Parametersfor2ndHarmonicA.C.Voltammetry

ParametersforAmperometrici-tCurve

ParametersforDifferentialPulseAmperometry

ParametersforDoubleDifferentialPulseAmperometry

ParametersforTriplePulseAmperometry

ParametersforIntegratedPulseAmperometricDetection

ParametersforBulkElectrolysiswithCoulomtery

ParametersforHydrodynamicModulationVoltammetry

ParametersforSweep-StepFunctions

ParametersforMulti-PotentialSteps

ParametersforA.C.Impedance

ParametersforImpedance-Time

ParametersforImpedance-Potential

ParametersforChronopotentiometry

ParametersforChronopotentiometrywithCurrentRamp

ParametersforMulti-CurrentSteps

ParametersforPotentiometricStrippingAnalysis

ParametersforOpenCircuitPotential-Time

Fordetailsoftheparametersofeachtechnique,seethedescriptionofindividualdialog

boxofrelatedtechniques.

Thiscommandhasatoolbarbutton:

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Chapter4.SetupMenu

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ParametersforCyclicVoltammetry

InCyclicVoltammetry(CV),potentialisscannedfromInitEtowardeitherHighEor

LowEdependingontheInitP/N.Thepotentialwillthenscanback.Thefollowingdiagram

showsthepotentialwaveformappliedasthefunctionoftime.Thecurrentisrecordedasthe

functionofpotential.

HighE

)

V

(

l

a

i

t

n

e

t

o

ScanRate(V/s)

P

InitE

LowE

Segment1

Segment2

Segment3

Time(s)

Thefollowingaretheexperimentalparameters,theirrangeanddescriptions:

Parameters

Range

Description

InitE(V)

-10-+10

-10-+10

-10-+10

Initialpotential

HighE(V)

Highlimitofpotentialscan

Lowlimitofpotentialscan

LowE(V)

InitP/N

PositiveorNegativeInitialscandirection

ScanRate(V/s)

SweepSegments

SampleInterval(V)

QuietTime(sec)

Sensitivity(A/V)

AutoSens

1e-6-20000

1-1000000

1e-6-0.064

0-100000

Potentialscanrate

Sweepsegments,eachsegmentsishalfcycle

Datasamplinginterval

Quiescenttimebeforepotentialscan

Sensitivityscale

1e-12-0.1

CheckorUncheck

Automaticsensitivityswitchingduringrun

Scancompletecycles

ScanCompleteCyclesCheckorUncheck

AuxiliarySignal

Recording

CheckorUncheck

Simultaneouslyexternalsignalrecording

whenthescanrateislessthan0.25V/s

Notes:

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Chapter4.SetupMenu

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1.HighEandLowEshouldbeatleast0.01Vapart.

2.IfunreasonableHighEandLowEareentered,thesystemwillautomaticallyreadjust

them.

3.DependingontheInitE,HighEandLowEvalue,thesystemwillautomaticallyreadjust

initialscandirection.

4.Themaximumpotentialscanrangeis13.1V.

5.Thepotentialincrementis0.1mVifthescanrateisbelow500V/s.Thepotential

incrementis1mVatthescanrateof5000V/s,and4mVat20000V/s.

6.Thesampleintervalcanbe1mVWhenthescanrateisbelow1000V/s.Thesample

intervalis2mVatthescanrateof2000V/s,5mVat5000V/s,and20mVat20000V/s.If

thescanrateishigh,thedatasamplingintervalwillbeautomaticallyincreased.

7.Whenlargenumberofsweepsegmentsareinvolved,thedatasamplingintervalwillbe

automaticallyincreasedupto0.02V.Ifthescanrateishigherthan0.5V/s,thenumberof

sweepsegmentswillbelimitedbythememorysize(64000points).Ifthescanrateisbelow

0.5V/s,themaximumdatalengthsetbytheSystemcommandwilltakeeffect.Whenthescan

rateislow,thespecifiedsweepsegmentswillbeexecuted,butonlylimitednumberof

segmentswillbestored.Largesweepsegmentsmightbeusefulforconditioningof

electrodes.

8.Whenscanrateisbelow0.01V/s,thesensitivityscaleduringruncanbeautomatically

switchedaccordingtothecurrentlevel.Whenitisactivated,thesensitivityselectionwill

havenoeffectonthemeasurement.However,theautomaticsensitivityswitchingrangewill

befrom1e-8-0.1A/V,insteadof1e-12-0.1A/V.ThePicoampBoosterwillnotwork

either.Inordertoselecthighersensitivities,automaticsensitivityswitchingoptionneedsto

bedisabled.

9.ScanCompleteCycleswillonlyworkforSweepSegmentsat3,5,7,9,(oddnumbers)

andifInitialEisdifferentfromHighEandLowE.Whenitworks,thelastsegmentwillstop

atInitialEinsteadofHighEorLowE.

10.Ifthescanrateislowerthan0.25V/s,itispossibletorecordexternalvoltagesignal(such

sspectroscopicsignal)simultaneouslywiththevoltammogram.Usethe9-pinD-connector

ontherealpanelforsignalinput.ChecktheUser'sManualforthepin-outandsignallevel

requirements.

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Chapter4.SetupMenu

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ParametersforLinearSweepVoltammetry

InLinearSweepVoltammetry(LSV),potentialisscannedfromInitEtowardFinalE.

Thefollowingdiagramshowsthepotentialwaveformappliedasthefunctionoftime.The

currentisrecordedasthefunctionofpotential.

FinalE

)

V

(

l

a

i

t

n

e

t

o

P

ScanRate(V/s)

InitE

Time(s)

Thefollowingaretheexperimentalparameters,theirrangeanddescriptions:

Parameters

InitE(V)

Range

Description

-10-+10

-10-+10

1e-6-20000

Initialpotential

FinalE(V)

ScanRate(V/s)

Finalpotential

Potentialscanrate

Datasamplinginterval

Quiescenttimebeforepotentialscan

Sensitivityscale

SampleInterval(V)1e-6-0.064

QuietTime(sec)

Sensitivity(A/V)

AutoSens

0-100000

1e-12-0.1

Checkor

Uncheck

Automaticsensitivityswitching

duringrun

AuxiliarySignal

Recording

Checkor

Uncheck

Simultaneouslyexternalsignal

recordingwhenthescanrateisless

than0.25V/s

Notes:

1.InitEandFinalEshouldbeatleast0.01Vapart.

2.Themaximumpotentialscanrangeis13.1V.

3.Whenthescanrateishigh,thedatasamplingintervalwillbeautomaticallyincreased.

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Chapter4.SetupMenu

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4.Thepotentialincrementis0.1mVifthescanrateisbelow500V/s.Thepotential

incrementis1mVatthescanrateof5000V/s,and4mVat20000V/s.

5.Thesampleintervalcanbe1mVWhenthescanrateisbelow1000V/s.Thesample

intervalis2mVatthescanrateof2000V/s,5mVat5000V/s,and20mVat20000V/s.If

thescanrateishigh,thedatasamplingintervalwillbeautomaticallyincreased.

6.Whenscanrateisbelow0.01V/s,thesensitivityscaleduringruncanbeautomatically

switchedaccordingtothecurrentlevel.Whenitisactivated,thesensitivityselectionwill

havenoeffectonthemeasurement.However,theautomaticsensitivityswitchingrangewill

befrom1e-8-0.1A/V,insteadof1e-12-0.1A/V.ThePicoampBoosterwillnotwork

either.Inordertoselecthighersensitivities,automaticsensitivityswitchingoptionneedsto

bedisabled.

7.Ifthescanrateislowerthan0.25V/s,itispossibletorecordexternalvoltagesignal(such

sspectroscopicsignal)simultaneouslywiththevoltammogram.Usethe9-pinD-connector

ontherealpanelforsignalinput.ChecktheUser'sManualforthepin-outandsignallevel

requirements.

8.LinearpolarizationresistanceplotcanbeobtainedbytheSpecialPlotscommandunder

theGraphicsmenu.

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Chapter4.SetupMenu

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ParametersforTafelPlot

InTafelPlot(TAFEL),potentialisscannedfromInitEtowardFinalE.Thepotential

maybescannedback.Thefollowingdiagramshowsthepotentialwaveformappliedasthe

functionoftime.Thelogarithmofcurrentisrecordedasthefunctionofpotential.

FinalE

)

V

(

HoldTime

l

a

i

t

n

e

t

o

P

ScanRate(V/s)

InitE

Segment1

Segment2

Time(s)

Thefollowingaretheexperimentalparameters,theirrangeanddescriptions:

Parameters

InitE(V)

Range

Description

-10-+10Initialpotential

-10-+10Finalpotential

FinalE(V)

SweepSegments

1-2

Sweepsegments,eachsegmentsishalfcycle

HoldTimeatFinalE(s)0-100000Potentialholdtimeatfer1stsweepsegent

ScanRate(V/s)

QuietTime(sec)

Sensitivity(A/V)

AutoSens

1e-6-0.1

Potentialscanrate

0-100000Quiescenttimebeforepotentialscan

1e-12-0.1Sensitivityscale

Checkor

Uncheck

Automaticsensitivityswitchingduringrun

Notes:

1.InitEandFinalEshouldbeatleast0.01Vapart.

2.CorrosionratecalculationcanbeobtainedbySpecialAnalysiscommandunderthe

Analysismenu.

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Chapter4.SetupMenu

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SystemCommand

Usethiscommandtosetuptheserialcommunicationport,currentpolarity,potentialaxis

andcurrentaxis.

ThiscommandpresentsaSystemSetupdialogbox:

Thefollowingoptionsallowyoutosetupyoursystem:

CommunicationPort

SelectthecommunicationporttolinkthePCtotheinstrument.

ComPortSpeed

SelectthecommunicationportspeedtolinkthePCtotheinstrument.Standardis

guaranteedtoworkwithanycomputer.Fastmayormaynotworkwithaparticular

computer.WhenFastischosen,therealtimedatatransferwillbedoneathigherscanrateor

shortersampleinterval.

CurrentPolarity

Youcaneitherselectcathodiccurrentaspositivecurrentoranodiccurrentaspositive

current.Youshouldsetthisbeforeexperiment,otherwisetheexperimentalresults(peaksand

waves)willnotbereportedproperly.

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Chapter4.SetupMenu

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PotentialAxis

Youcansetpositivepotentialaxiseitherleftorright.Thisismeaningfulonlyfor

voltammetricorpolarographicmodes.

CurrentAxis

Youcansetpositivecurrentaxiseitherupordown.

LineFrequency

Setlinefrequencyaccordingtowhatisapplied.Thishelpssetdefaultsampleintervalin

certaintechniquestoreducetheinterferencefromthelinefrequency.

Windows

ifyouareusingEnglishWindows,pleasechooseEnglish.IfyouareusingChinese,

Japanese,orKoreanWindows,checkOriental.OrientalWindowsshowsslightlybigger

lettersthanEnglishWindows.TheTechniqueselectionfieldmaybetruncatedifyouselect

EnglishWindows.AlsoorientalWindowsdoesnotsupportcertainsymbols.Forinstance,

symbol"µ"willnotbedisplayedproperly.ChooseorientalWindowswilluse"u"insteadof

"µ".

DataLength

Thedefaultdatalengthis128K.Thelongerthedatalength,themorecomputerresource

willbeused.Itisrecommendednottouselongdatalengthunlessnecessary.Usinglongdata

lengthwillneedlargecomputermemorysuchas256M,512MRAMormore.Itwillalso

slowdownthesystemandprohibitotherprogramstorun.

AfteryouchangethedatalengthsettingintheSystemSetupcommand,pleaseexitthe

programandrestarttheprogramsothatthedatalengthcanbesetproperly.Otherwisethe

programmaycrash.

Ifthedataisacquiredandsavedwithlongdatalengthsetting,butreadbackwithshorter

datalengthsetting,theprogrammaycrash.Thereforeonceyouusedlongdatalengthsetting,

youshouldnotsettoshorterdatalengthlater.Pleasethinkcarefullybeforeyoudecideto

increasethedatalength.

Saveretrievedataduringrun

Checkthisoptionwillallowdatatobesavedontheharddriveduringrun.Incase

experimentdoesnotcompleteduetoexternalinterferenceorinterruption,miss

communication,partialdatacanberecovered.Thisisusefulforveryslowexperiments.

Hoursofexperimentaldatacanberecovered.

Thisoptionisnotactivebydefault.Ifyoudonotrunveryslowexperiments,youcanre-

runtheexperimentiftheexperimentisinterruptedbyaccident.

Toretrieveexperimentaldataoflastrun,youshoulduseRetrievecommandunderthe

Filemenu.

PresentDataOverrideWarning

Ifyourexperimentaldataisnotsavedbeforerunninganewexperimentoropeningan

existingfileonthedisk,yourunsaveddatawillbeoverridden.Thisoptionwillallowsystem

toissueawarningbeforethedataislost.

SaveTextFileAsWell

Normallyonlybinarydatafilesissaved.Binaryfilecontainsmoreinformation

(includingexperimentalcontrolinformation)butsmallinsize.Thisoptionallowsyouto

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Chapter4.SetupMenu

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savetextfileaswellwheneveryousavethebinarydata.Thisisusefulforthosewhowantto

exportdatatoothersoftware,suchasspreadsheetsoftware.

EraseADCCalibrationCoefficients

Theanalog-to-digitalconverter(ADC)calibrationcoefficientsarestoredinthe

instrumentnon-volatilememory.ADCcalibrationiscarriedoutinCHInstrumentsbeforethe

instrumentisshipped.YouusethiscommandonlyifyouwanttorecalibratetheADC.After

youeraseADCcalibrationcoefficients,youwillseeapromptofADCcalibrationwhenyou

runnexthardwaretestorexperiment.

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Chapter4.SetupMenu

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HardwareTestCommand

Usethiscommandtotestthesystemhardware.Thesystemwilltestdigitalandanalog

circuitry.

Afterthetest,thesystemwilldisplaytheHardwareTestResultsdialogbox:

DigitalCircuitryTest

ThesoftwareversionandthelastrevisiondatefortheFlashROMisshown.

Potentialandcurrentoffsettest

Iftestisfailed,theerrormessagewillbegiven.

Sensitivityscaletest

Iftestisfailed,theerrormessagewillbegiven.Mosttimestheerrorisrelatedtoleakage

current.

Gaintest

Thereare3gainstages.Iftestisfailed,theerrormessagewillbegiven.

AnalogTestSummary

Thetestresultsofanalogcircuitryaresummarized.Amessageof“Analogcircuitrytest

OK.”willappearifnoerrorisdetected,otherwiseanerrormessagewillappear.Incasethere

iserrorandthecauseisduetotheanalog-to-digitalconverters,itwillalsobereported.

Ifyouseeanalogtesterror,pleaserepeatthetestseveraltimesandseeiftheerroris

consistent.Recordtheerrormessageandcontactthefactoryforservicing.

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Chapter5.ControlMenu

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OpenCircuitPotentialCommand

Usethiscommandtomeasuretheopencircuitpotential.

Theopencircuitpotentialisthepotentialbetweentheworkingelectrodeandreference

electrodewhilenocurrentflowsthroughthecell.Thisisanimportantparameter.Ittellsyou

whatistheinitialstatebeforeyoustartexperiment.Youcanthenfigureoutifthecompound

understudyisoxidizableorreducible.

Afterthemeasurement,thesystemwilldisplaytheopencircuitpotentialvaluethrough

theOpenCircuitPotentialdialogbox.ClickOKtoclosethedialogboxafteryoureadit.

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Chapter5.ControlMenu

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iRCompensationCommand

Usethiscommandtotestthesolutionresistanceandthecelltimeconstant,aswellasto

enableordisableautomaticormanualiRcompensation.

ThiscommandpresentsaniRCompensationdialogbox:

ThefollowingoptionsallowyoutosetiRcompensationparameters:

iRCompTestResults

IfyouclicktheiRTestbutton,thesystemwillengagesolutionresistanceandcelltime

constanttest.Theresultwillbereportedhere.

Afterthatthesystemwilltestthestabilitybygraduallyincreasethecompensationlevel

untilthedesiredcompensationlevelisreachedorifthesystemisnolongerstable.The

actuallyallowedcompensationlevelandtheuncompensatedresistancewillbedisplayed.

Theuncompensatedresistanceiscalculatedfromthemeasuredresistanceandtheallowed

compensationlevel.

Pleasenotethatthemaximumallowedresistancecompensationmayalsobelimitedto

thefeedbackresistorofthei/Econverter.

iRCompTest

BeforestartiRcompensationtest,youshouldcheckthetestparameters.

TestEisthetestpotentialwherenoelectrochemicalreactionwilloccur.Whenthe

systemisdoingtest,itappliesapotentialsteparoundthetestpotential.Thetestresultis

goodonlyiftheelectrochemicalcellcanbeequivalenttoasolutionresistanceinserieswith

adoublelayercapacitor.TherangeofTestEis-10V-+10V.

Youmayadjustthepotentialstepamplitude.Thelargertheamplitude,thehigherthe

signal-to-noiseratio.However,toolargeamplitudemaycausefaradaiccurrenttoflow.A

stepamplitudeof0.05Visrecommended.TherangeofStepAmplitudeis0.01-0.25V.

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Chapter5.ControlMenu

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Thecompensationlevelisthepercentageofresistanceyouwanttocompensatebasedon

themeasuredsolutionresistance.Therangeofthisparameteris0-200%.Thedefaultvalue

is100%.

Overshootlevelisthecriterionofthestabilitytest.Astheamountofpositivefeedback

increases,thesystemmightbec