简介:Amonolithichybridfuelcell(MHFC)withanovelconfigurationwasproposedinanefforttoimprovethefuelcellperformanceduringinstantaneouspowerchanges.Amodifieddirectmethanolfuelcell(DMFC)withalayerofhydrousrutheniumdioxide(RuO2·xH2O)sandwichedbetweentheanodecatalystlayerandmembranewasusedtodemonstratetheprincipleoftheMHFC.ExperimentalresultsindicatethattheRuO2·xH2Olayerisequivalenttoaresistor-capacitortransmissionlineandfunctionssimilartoacapacitorinparallelwiththeanodeelectrode.TheimprovementindynamicresponseoftheMHFCwasexperimentallyconfirmedunderstepcurrentchangeandsquarecurrentpulseoperating.TheionicconductivityoftheRuO2·xH2Olayerwasalsoobtained.
简介:Inrecentyears,developmentofhigh-performancesupercapacitorelectrodematerialshasstimulatedagreatdealofscientificresearch.Theelectrochemicalperformanceofasupercapacitorstronglydependsonitsmaterialstructures.Herein,wereportasimplestrategyforhigh-performancesupercapacitorsbybuildingpseudocapacitiveCuSnanosphereswithnanoporousstructures,nanosizedwalls(<10nm)andrelativelylargespecificsurfaceareaof65m~2/g.Thiselectrodedemonstratesexcellentelectrochemicalperformanceincludingamaximumspecificcapacitanceof814F/gat1A/g,significantratecapabilityof42%capacitanceretentionatanultrafastrateof50A/g,andoutstandinglong-termcyclingstabilityatvariouscurrentdensities.Theremarkableelectrochemicalperformanceofas-preparednanoporousCuSnanosphereselectrodehasbeenattributedtoitsuniquestructuresthatplaysakeyroleinprovidingshortionandelectrondiffusionpathways,facilitatediontransportandmoreactivesitesforelectrochemicalreactions.Thisworkshedsanewlightonthemetalsulfidesdesignphilosophy,anddemonstratesthatnanoporousCuSnanosphereselectrodeisapromisingcandidateforapplicationinhigh-performancesupercapacitors.
简介:Effectofstackingstructureofsingle-walledcarbonnanotubes(SWCNTs)onitsperformanceaselectrodeofsupercapacitorwasinvestigatedinthepresentwork.ConsideringSWCNTseasilyformedbundlesduetostrongvandeWaalsattractionbetweentubes,weproposedfirstdispersionofSWCNTsbyionicliquids(ILs)of1-ethyl-3-methylimidazoliumtetrafluoroborate(EMIMBF4),followedbyfabricationofbuckypaperbycompression.ThedebundlingeffectofILsonSWCNTsincreasedtheinterfacebetweenelectrodeandelectrolyte,decreasedelectricalresistance,and,consequently,increasedperformanceofthesupercapacitor.SinceILs,usedtodisperseSWCNTs,alsofunctionedaselectrolyteinsupercapacitor,ourmethodisasimplewaytopreparebuckypaperelectrodewithhighperformance.
简介:Immobilizingbiocomponentsonsolidsurfacesisacriticalstepinthedevelopmentofnewdevicesforfuturebiological,medical,andelectronicapplications.Therefore,numerousintegratedfilmswererecentlydevelopedbyimmobilizingdifferentproteinsorenzymesonelectrodesurfaces.Inthiswork,hemeproteinsweresafelyimmobilizedontomacroporousnickel-basedelectrodeswhilemaintainingtheirfunctionality.Suchmodifiedelectrodesshowedinterestingpseudo-capacitivebehavior.Amonghemeproteins,hemoglobin(Hb)filmhasahigherelectrochemicalperformanceandgreatercharge/dischargecyclingstabilitythanmyoglobin(Mb)andcytochromeC(CytC).Thehemegroupinanalkalinemediumcouldinducetheformationofsuperoxidesontheelectrodesurface.Thesecapacitivefeaturesofhemeprotein-NielectrodewererelatedtostrongbindingsitesbetweenhemeproteinsandporousNielectrode,theaccumulationofsuperoxideorradicalsontheNisurface,andfacileelectrontransferandelectrolytediffusionthroughthethree-dimensionalmacroporousnetwork.Thus,thesenewprotein-basedsupercapacitorshavepotentialuseinfree-standingplatformtechnologyforthedevelopmentofimplantableenergy-storagedevices.
简介:一个有效方法被用来在N生产高度减少的graphene氧化物(RGO)的稳定、同类的胶体的暂停,没有驱散代理人的帮助的N-dimethylformamide(DMF)。根据一般描述的结果,有单个层或很少层结构的形态学的相对纯的graphene表被获得。然后,RGO并且poly的nanocomposite粉末(vinylidene氟化物)(PVDF)被两个部件的混合分散的真空过滤准备。nanocomposites展览有在0.4点的小相等的系列电阻(ESR)的高周波的capacitative回答,将近矩形的周期的voltammogram并且在5mol/LKOH电解质为supercapacitor作为电极拥有快速的当前的回答。在600个galvanostatic控告/解除周期以后,而且,supercapacitor仍然执行电容的很高的稳定性和效率。
简介:Two-dimensional(2D)metalcarbides,MXene,presentthepromisingapplicationfortheenergystoragesystem.AmongtheMXenefamily,Ti2CTxasthelightestmaterial,showsitsuniqueelectrochemicalperformance.Herein,Ti2CTxissynthesizedbyselectiveetchingAllayerfromtheTi2AlC.WiththeoptimizedHFtreatingcondition,Ti2CTxdisplayshighvolumetriccapacitaneeandremarkablerateability.Moreover,theTi2CTx//Ti2CTxsymmetricsupercapacitorisdesignedandassembled,whichpresentscapablecapacitance,outstandingrateperformanceandexcellentcyclingperformance.Theremarkableelectrochemicalperformanceisattributedtoits2Dstructureandhighelectronicconductivity.ThisworkdemonstratesthepotentialapplicationoftheTi2CTxforthesupercapac让o「sandprovidesatemplatetodesignhighperformancesupercapacitorswith2Delectrodematerials.
简介:Afree-standingpaper-likethree-dimensionalgrapheneframework(3DGF)withorientatedlaminarstructureandinterconnectedmacropores,wasobtainedbythehardtemplate-directedorderedassembly.Asthesacrificialtemplates,polystyrene(PS)latexsphereswereassembledwithgrapheneoxide(GO)tobuildupasandwichtypecompositefilm,followedbyheatremovalofwhichwithasimultaneousreductionofGO.The3DGFexhibitedhighspecificsurfaceareaof402.5m2/g,controllableporesandmechanicalflexibility,whichwasemployedasthebinder-freesupercapacitorelectrodeandshowshighspecificgravimetriccapacitanceof95F/gat0.5A/g,withenhancedratecapabilityin3electrodeKOHsystem.
简介:Facileproductionofhighqualityactivatedcarbonsfrombiomassmaterialshasgreatlytriggeredmuchattentionpresently.Inthispaper,aseriesofinterconnectedporouscarbonmaterialsfromlotusrootshellsbiomassarepreparedviasimplepyrolysisandfollowedbyaKOHactivationprocess.Thepreparedcarbonsexhibithighspecificsurfaceareasofupto2961m~2/gandlargeporevolume~1.47cm3/g.Inaddition,theresultantporouscarbonsservedaselectrodematerialsinsupercapacitorexhibithighspecificcapacitanceandoutstandingrecyclingstabilityandhighenergydensity.Inparticular,theirspecificcapacitanceretentionwasalmost100%after10500cyclesatacurrentdensityof2A/g.Remarkabely,theimpactofthetailoredspecificsurfaceareasofvariouscarbonsamplesontheircapacitiveperformancesissystematicallyinvestigated.Generally,itwasbelievedthatthehighly-developedporosityfeatures(includingsurfaceareasandporevolumeandporesize-distributions),togetherwiththegoodconductivityofactivatedcarbonspecies,playakeyroleineffectivelyimprovingthestorageenergyperformancesoftheporouscarbonelectrodematerialsinsupercapacitor.
简介:Hydrousrutheniumoxide(h-RuO2)nanoparticlesanditscompositewithmultiwalledcarbonnanotubes(h-RuO2/MWCNT)weresynthesizedbyasimplehydrothermalmethodandprovedtohavepotentialapplicationashybridsupercapacitormaterial.Theh-RuO2andh-RuO2/MWCNTwerecharacterizedfortheirphysico-chemicalpropertiesbyPXRD,BETsurfacearea,Raman,SEM-EDSandTEMtechniques.Theelectrochemicalperformanceofthematerialswereinvestigated,specificcapacitance(Cs)ofh-RuO2andhRuO2/MWCNTestimatedbytheircyclicvoltammetricstudieswerefoundtobe604and1585F/grespectivelyatascanrateof2mV/sinthepotentialrange0–1.2V.Further,thisvaluewasfoundtobenearlythreetimeshigherthanthatofpureh-RuO2.Anasymmetricsupercapacitor(AS)devicewasfabricatedbyemployingh-RuO2/MWCNTasthepositiveelectrodeandactivatedcarbonasthenegativeelectrode.ThedeviceexhibitedCsof61.8F/gatascanrateof2mV/s.Further,thedeviceshowedexcellentlongtermstabilityfor20,000cycleswith88%capacitanceretentionatahighcurrentdensityof25A/g.
简介:Inpursuingexcellentsupercapacitorelectrodes,wedesignedaseriesofM0S2/C0S2compositesconsistingofflower-likedMoS2andoctahedron-shapedCoS2throughafacileone-stephydrothermalmethodandinvestigatedtheelectrochemicalperformanceofthesampleswithvarioushydrothermaltime.Duetothecouplingoftwometalspeciesandabigamountofwell-developedCoS2andMoS2,theresultsindicatedthattheMoS2/CoS2compositeselectrodesexhibitedthebestelectrochemicalperfor-mancewithalargespecificcapacitanceof490F/gat2mV/sor400F/gat10A/gamongallsamplesasthehydrothermaltimereached48h(MCS48).Furthermore,theretentionofMCS48is93.1%after10000cyclesat10A/g,whichmanifeststheexcellentcyclingstability.TheoutstandingelectrochemicalperformanceofMCS48indicatesthatitcouldbeaverypromisingandnovelenergystoragematerialforsupercapacitorsinthefuture.