研究生英语文献汇报PPT

1PaperReview李俊乾化学工程（专）14102932SynthesisofbimetallicPt/Pdnano-tubesandtheirenhancedcatalyticactivityinmethanolelectro-oxidation（双金属铂/钯纳米管的合成和其在甲醇电氧化增强的催化活性）2Literaturesource3ContentsIntroduction12Experimentalsection1Conclusions234Resultsanddiscussion41.IntroductionTheshortageoftraditionalenergyresourcesandseriousenvironmentalpollutionduetocombustionemissionshaveresultedinanumberofscientificstudiesonthedevelopmentofsustainableandcleanenergy,includingfuelcells.51.IntroductionMethanoloxidationinadirectmethanolfuelcell(DMFC)cangenerateelectrochemicalenergy.DMFC’Sworkingprinciple:CathodePolymerAnodemembraneCO2H2OH2OCO2H2OO2H+：CH3OHe-e-Loadinge-CathodecatalystAnodecatalystWasteheatAnode：CH3OH+H2OCO2+6H++6e-φ0=0.046VCathode：3/2O2+6H++6e-3H2Oφ0=1.229VCH3OH+3/2O2CO2+2H2OE0=1.183VThisoxidationusuallyneedsacatalysttolowerthereactionbarriertomaketheprocessefficient.Sofar,platinum(Pt)isthemostefficientcatalystinthefield.ScarcityofPt,whichcausesitshighcost,inevitablyimpedestheactivedevelopmentofbothscientificresearchandpracticalutilization.Theutilizationofsingle-componentPtinDMFCssuffersfromseriouscarbonmonoxide(CO)poisoning.CO,oneofthemainintermediatemolecules,caneasilystainPtatoms,whichdeterioratestheircatalyticactivity.6Thearticlethought：Inthisstudy,weachievedhighercatalyticactivityformethanoloxidationusingtheperpendicularbimetallicPt/PdNTarrayasacatalyst.TheinvestigationofthecatalyticpropertiesofbimetallicmaterialspavesawaytosubstitutingexpensivePtwithcost-competitivematerialsinthefuture.7Experimentalsection282.Experimentalsection5mMPdCl25mMH2PtCl640mMHClusedfordepositionThelengthsoftheNTscanbecontrolledbyusing0.3to2C.AAOavertically-alignedbimetallicPt/PdnanotubearrayScheme1Schematicdrawingoftheiondistributioninaporousaluminanano-template.DashedlinesshowtheelectricaldoublelayeroftheclassicalGouy–Chapman–Stern'smodelbetween(b)diffusionlayerand(c)bulklayerregionsinananochannel.Region(a)depictsacompactlayer.923Resultsanddiscussion103.ResultsanddiscussionTheaverageouterdiameterandwallthicknessofthePt/PdNTsweremeasuredas217(39nm)and37(12nm),respectively.AsshownintheSEMimages,theresultingmorphologyofthenanostructureswasquitehomogeneousoveralargeareaofthesample.SynthesisofbimetallicPt/Pdnano-tubesandmorphologyanalysis113.ResultsanddiscussionAsthePt/Pdratioincreased(i.e.,theproportionofPt4+increased),thenanostructuresbecamerodshapes.AsthePt/Pdratiodecreased(i.e.,theconcentrationofPd2+increased),thenanostructuresgraduallystartedtoshowanopennano-tubular(ONT)shape.123.ResultsanddiscussionWhen5mMPdand5mMPtprecursorionswereintheplatingsolution,Pt49/Pd51NTscouldbepreparedAplotofatomic%ofPtinPt/Pdbimetallicnanostructuresvs.amountofPtsource133.Resultsanddiscussion(A)TEMimageofPt/PdNTswith1C(2.40.4mm)showsthetotallytubularstructurefrombottomtotop.(B)TEMimageofaPt/PdNTandline-scanningprofilesintheradialdirection,indicatingPt(redtrace)andPd(greentrace)distributions.Thecorrespondingelementalmappingimagesareshownfor(C)Ptand(D)Pd.143.ResultsanddiscussionFE-SEMimages(BSEmode)ofthePt/PdNTs.ThelengthsofthePt49/Pd51NTsweretunedbyusing(A)0.3C,(B)1Cand(C)2C.(D)ThePt/PdNTshaveaveragelengthsfrom1.1±0.1mmto4.9±0.9mm.153.Resultsanddiscussion返回Electro-catalyticproperties(A)Cyclicvoltammograms(CVs)ofPtand/orPdnanostructureswithsamelengths(ca.2.4mm)in0.5MH2SO4solutionatroomtemperature.AsshowninFig.A,thevalueofthesurfacechargeofthePt/PdNTcatalystswasfoundtobe1.7timeslargerthanthatofthePt/PdNRs.163.Resultsanddiscussion(B)AnodicstripingofCOoxidationin0.5MH2SO4aqueoussolutionfordifferentcatalysts(onlytheoxidativeCOremovalregionisshown).TheobservedpeakintensityofCOoxidationonthePt/PdNRswastwotimeshigherthanthatofthepurePtandPdNRs.Interestingly,theonsetpotentialofCOoxidationforthePt/Pdbimetallicnanostructures(0.61V)appearedatalowerpotentialcomparedtothepurePtNRs(0.69V)andthepurePdNRs(0.79V).173.Resultsanddiscussion(C)Cyclicvoltammogramsofmethanoloxidationusingdifferentcatalysts.TheinsetimageshowsthemagnifiedonsetpotentialregionoftheCVs.TheJf/JbratiosofthePt/PdNTsandPtNRsweredeterminedtobe1.6and1.2,respectively.TheVonsetwasfoundtobeintheorder:Pt/PdNTs(0.42V)Pt/PdNRs(0.44V)PtNRs(0.49V)183.Resultsanddiscussion(D)Comparisonofchronoamperogramsofmethanoloxidationfordifferentcatalystsat0.4V(vs.Ag/AgCl).Electrolyteformethanoloxidation:0.5MH2SO4and0.2MCH3OHsolutionatroomtemperature.Scanrate:50mVs-1.WefoundthatPt/PdNTsshowedthehighestcurrentdensitycomparedtoothernanostructures.19Conclusions4204.conclusions1、WedemonstratedafacileroutetosynthesizehighlyorderedPt/Pdbimetallicnano-tubeelectrodesbasedonanAAOtemplate-directedelectrochemicalmethod.2、TheperpendicularPt/Pdbimetallicnano-tubespresentedinthismanuscriptarepotentiallyusefulasenhancedelectro-catalystsinmethanolorothertypesoffuelcell.21Thankyouforyourattention!