Introduction-of-MXenePPT课件

IntroductionofMXene-anewfamilyof2Dmaterials,1,.,MAXphasematerials:Mn+1AXn,WhatisMAXphasematerials?,2,.,WhatisMXene?,Etching,Mxene:Mn+1Xn,3,.,SynthesisofMXene,Principle:EtchingtheAlayer(normallyAl),Problem:BondingofM-A:Strong,Iftooharsh,Conditions:ParticleSizeConcentrationTemperatureTime,etchingenvironmentmaybeharsh,AqueousHF,4,.,SynthesisofMXene,5,.,SynthesisofMXene,(0002),(0002),6,.,SynthesisofMXene,Sonicationinisopropylalcoholormethanol,7,.,IntercalationandDelamination,8,HMinDMFUreaDMSO,.,9,Energyscheme,TotalandpartialDOSofTi2AlC,Ti2C,Ti2CO2andTi2C(OH)2,illustratingchangesinthedensityofstatesuponremovalofAlfromtheparentMAXphasetoproduceMXene,andfurtherchangesuponterminationoftheMXenesurfacebydifferentT.,.,ApplicationinEnergyStorageLIB,10,Highlight:decentcapacitancewithverygoodcyclingperformance,.,ApplicationinEnergyStorageSCs,vs.EDLC:specificsurfacearea?Notverylarge,especiallycomparedwithgraphene500forsinglelayerMXenevs.Pseudocapacitor:redoxreaction?Notsosufficient(somereactionsmayhappenbetweentransitionmetalcarbideandelectrolyte),Mostsignificantadvantage:ConductivityandMachinability,KeyWords:Additive-freeandflexible,11,.,ApplicationinEnergyStorageSCs,Filmelectrodes,530Fcm-3KOH/PVA2mVs-1,12,.,ApplicationinEnergyStorageSCs,Clay-likeelectrode,900Fcm-3H2SO42mVs-1245Fg-1H2SO42mVs-1,13,.,ApplicationinEnergyStorageSCs,ImpressivevolumetriccapacitanceDecentgravimetricallycapacitance,Why?,asmalltrick:largedensityofMXene,thuslargevolumetriccapacitanceifthegravimetriccapacitanceisthesame,14,.,KOH,MgSO4,ApplicationinEnergyStorageSCs,15,.,ApplicationinEnergyStorageSCs,Cationswillintercalateintothegaps:radiiofcationselectricvalues,H+isverysmallIntercalationismucheasierPossibleredoxreactionwithtransitionmetalcarbide,16,.,PossibleDirectionsforus,SynthesisofMXene:,GreenProcess:replacinghazardouschemicals:HF,LiF+HCl,etcNaOH+H2SO4,17,.,18,GreenProcess:replacinghazardouschemicals:HF,LiF+HCl,etcElectrochemical“dealloying”ofAllayers,PossibleDirectionsforus,SynthesisofMXene:,IntrinsicgoodelectricconductivityMachinability(clay-likefeature),ConductiveFilm(filtration,pressing),ElectrochemicaldealloyingasforalloysorBMGribborns,.,PossibleDirectionsforus,ApplicationinSCs:,Flexibl