聚苯胺超级电容器性能(3)

Electrochemicalimpedancespectroscopy(EIS)wasfurtheremployedatadcbiasof0Vtomonitortheelectrochemicalbehav-iorofthecompositeelectrodes.Fig.7isNyqusitplotsforthePANI,PANI/CMK-3/MnO2-2andPANI/CMK-3electrodesinthesameelec-trolytewithafrequencyloopfrom100kHzto10mHzusingaperturbationamplitudeof5mV.Eachimpedancecurveshowsasinglesemicircleinthehigh-frequencyregionandastraightlineinthelow-frequencyregion.Thediameterofsemicirclepresentsthecharge-transferresistance(Rct)intheelectrochemicalsystem.ThesemicirclediameterofPANI/CMK-3/MnO2-2compositeelectrodeismuchsmallerthanthatofpurePANIandPANI/CMK-3composite,whichindicatesthattheternarycompositehasthelowestelectro-chemicalcharge-transferresistance.ThisexperimentresultfurtherprovesthattheCMK-3modi edwithMnO2nanoparticlesanduni-formPANInanolayercanleadtoafasterelectrontransportin

the

Fig.7.NyquistplotsforPANI,PANI/CMK-3/MnO2-2,andPANI/CMK-3electrodesatafrequencyrangefrom100kHzto10mHz.TheinsetshowsthehighfrequencypartoftheNyquist

plots.

Fig.8.CyclingperformanceofPANI/CMK-3/MnO2-2andPANI/CMK-3underacur-rentdensityof1Ag 1.

compositeandfasterchargetransferintheparallelPANI/solutioninterface[33].

Thestabilityandreversibilityofanelectrodematerialareimpor-tantforitsuseinanelectrochemicalsupercapacitor.ThecyclicperformanceofPANI/CMK-3/MnO2-2andPANI/CMK-3wasmea-suredbygalvanostaticcharge-dischargetestsatacurrentdensityof1Ag 1.AsshowninFig.8,thespeci ccapacitanceofPANI/CMK-3retained90%after1000charging/dischargingcycles.Underthesamecondition,thecapacitanceretentionofPANI/CMK-3/MnO2-2is88%.TheslightlydepressedelectrochemicalstabilityoftheternarycompositecanbeexplainedfortheintroductionofMnO2.However,after1000cyclesthespeci ccapacitanceofPANI/CMK-3/MnO2-2stabilizesat570Fg 1,whichismuchhigherthanthatofCMK-3/PANI.Thisfurthercon rmsthattheincorporationofappro-priateamountofMnO2nanoparticlescansigni cantlyenhancethespeci ccapacitanceofternarycompositeelectrodeinacidicelectrolyte.

4.Conclusions

TheCMK-3/MnO2compositewasprepared rstbythedirectreactionbetweentheoxidant(KMnO4)andthereductant(CMK-3).Then,newPANI/CMK-3/MnO2ternarycompositesweresuccess-fullysynthesizedviainsituchemicaloxidativepolymerization.TheintroductionofMnO2nanoparticlescanstabilizetheinteractionbetweenthequinoidringofPANIandtheCMK-3/MnO2parti-cles.TheternarycompositecanoperateinacidicelectrolyteduetotheprotectivematrixofPANI.Electrochemicalmeasurementsindicatedthattheternarycompositewith12%MnO2nanoparticlesshowedhighercapacitancevaluethanthebinarycompositeandpurePANI.EISmeasurementprovedthatCMK-3/MnO2compos-itesprotectedwithPANInanolayerinacidicelectrolytepossessedareducediondiffusionresistanceandchargetransferresistanceincontrastwithPANI/CMK-3binarycomposites.

Acknowledgements

ThisworkwassupportedbytheNationalNaturalScienceFoundationofChina(20925621),theSpecialProjectsforKeyLaboratoriesinShanghai(10DZ2211100),theSpecialProjectsforNanotechnologyofShanghai(1052nm02300),theShang-haiPujiangProgram(09PJ1403200),theBasicResearchProgramofShanghai(10JC1403300and10JC1403600),theFundamentalResearchFundsfortheCentralUniversitiesandtheprojectspon-soredbySRFforROCS,SEM.

超级电容器

32Y.Yanetal./ElectrochimicaActa71 (2012) 27–32

References

[1]M.Winter,R.J.Brodd,Chem.Rev.104(2004)4245.

[2]V.Subramanian,H.Zhu,R.Vajtai,P.M.Ajayan,B.Wei,J.Phys.Chem.B109

(2005)20207.

[3]V.Subramanian,H.W.Zhu,B.Q.Wei,mun.8(2006)827.[4]P.Simon,Y.Gogotsi,Nat.Mater.7(2008)845.

[5]J.H.Jiang,A.Kucernak,Electrochim.Acta47(2002)2381.[6]R.N.Reddy,R.G.Reddy,J.PowerSources124(2003)330.

[7]R.K.Sharma,H.S.Oh,Y.G.Shul,H.Kim,J.PowerSources173(2007)1024.[8]P.K.Nayak,N.Munichandraiah,Micropor.Mesopor.Mater.143(2011)206.[9]J.W.Long,C.P.Rhodes,A.L.Young,D.R.Rolison,NanoLett.3(2003)1155.

[10]S.Yoon,C.Lee,S.M.Oh,Y.K.Park,W.C.Choi,J.Non-cryst.Solids355(2009)252.[11]M.N.Patel,X.Q.Wang,B.Wilson,D.A.Ferrer,S.Dai,K.J.Stevenson,K.P.Johnston,

J.Mater.Chem.20(2010)390.

[12]X.P.Dong,W.H.Shen,J.L.Gu,L.M.Xiong,Y.F.Zhu,H.Li,J.L.Shi,J.Phys.Chem.B

110(2006)6015.

[13]S.M.Zhu,H.S.Zhou,M.Hibino,I.Honma,M.Ichihara,Adv.Funct.Mater.15

(2005)381.

[14]S.Nijjer,J.Thonstad,G.M.Haarberg,Electrochim.Acta46(2000)395.

[15]Jaidev,R.I.Jafri,A.K.Mishra,S.Ramaprabhu,J.Mater.Chem.21(2011)17601.[16]D.S.Dhawale,A.Vinu,C.D.Lokhande,Electrochim.Acta56(2011)9482.

[17]K.S.Ryu,K.M.Kim,N.G.Park,Y.J.Park,S.H.Chang,J.PowerSources103(2002)

305.

[18]D.S.Dhawale,D.P.Dubal,V.S.Jamadade,R.R.Salunkhe,C.D.Lokhande,Synth.

Met.160(2010)519.

[19]C.Z.Yuan,L.H.Su,B.Gao,X.G.Zhang,Electrochim.Acta53(2008)7039.

[20]J.Yan,T.Wei,Z.J.Fan,W.Z.Qian,M.L.Zhang,X.D.Shen,F.Wei,J.PowerSources

195(2010)3041.

[21]Q.Li,J.H.Liu,J.H.Zou,A.Chunder,Y.Q.Chen,L.Zhai,J.PowerSources196(2011)

565.

[22]Y.Hou,Y.W.Cheng,T.Hobson,J.Liu,NanoLett.10(2010)2727.

[23]D.Y.Zhao,J.L.Feng,Q.S.Huo,N.Melosh,G.H.Fredrickson,B.F.Chmelka,G.D.

Stucky,Science279(1998)548.

[24]S.Jun,S.H.Joo,R.Ryoo,M.Kruk,M.Jaroniec,Z.Liu,T.Ohsuna,O.Terasaki,J.

Am.Chem.Soc.122(2000)10712.

[25]X.Jin,W.Zhou,S.Zhang,G.Z.Chen,Small3(2007)1513.

[26]C.H.Kim,S.-S.Kim,F.Guo,T.P.Hogan,T.J.Pinnavaia,Adv.Mater.16(2004)736.[27]A.P.Monkman,P.Adams,Synth.Met.40(1991)87.

[28]A.B.Yuan,Q.L.Zhang,mun.8(2006)1173.

[29]S.I.A.Razak,A.L.Ahmad,S.H.S.Zein,A.R.Boccaccini,Scr.Mater.61(2009)

592.

[30]C.C.Hu,J.Y.Lin,Electrochim.Acta47(2002)4055.

[31]J.Yan,T.Wei,B.Shao,Z.J.Fan,W.Z.Qian,M.L.Zhang,F.Wei,Carbon48(2010)

487.

[32]Y.G.Wang,H.Q.Li,Y.Y.Xia,Adv.Mater.18(2006)2619.

[33]J.Zhang,L.B.Kong,J.J.Cai,Y.C.Luo,L.Kang,Electrochim.Acta55(2010)

8067.