预览加载中,请您耐心等待几秒...
1/2
2/2

在线预览结束,喜欢就下载吧,查找使用更方便

如果您无法下载资料,请参考说明:

1、部分资料下载需要金币,请确保您的账户上有足够的金币

2、已购买过的文档,再次下载不重复扣费

3、资料包下载后请先用软件解压,在使用对应软件打开

一种制备可膨胀石墨的新方法 Introduction Graphene,amaterialwithuniqueproperties,isbeingusedinvariousfields.However,theinabilityofgraphenetoexpandlimitsitsapplicationinenergystoragedevices.Thus,therehasbeenagrowinginterestindevelopingmethodstofabricateexpanded-graphiteorexfoliatedgraphite,whichcanbeusedinmanyapplications.Oneofthemostpromisingmethodsforpreparingexpandedgraphiteistheoxidation-exfoliationapproach.Inthismethod,naturalgraphiteistreatedwithstrongoxidants,suchassulfuricacidandpotassiumpermanganate,followedbyathermaltreatment,resultingintheexfoliationofgraphite.Nevertheless,thismethodisenergy-intensiveandhighlyhazardous.Thus,thereisaneedforasaferandmoreenvironmentallyfriendlymethodforpreparingexpandedgraphite. Inthispaper,wepresentanewapproachforthepreparationofexpandablegraphitethatissaferandmoreeco-friendlythanthepreviouslyusedmethods.Thismethodinvolvestheuseofmicrowaveradiationtoinduceintercalationofgraphitewithpotassiumsaltsandsubsequentthermaltreatmenttoobtainexpandedgraphite. Experimental Materials:Graphiteflakes,potassiumcarbonate(K2CO3),andpotassiumhydroxide(KOH)werepurchasedfromSigma-Aldrich. Preparationofexpandablegraphite:Initially,10gofgraphiteflakesweremixedwith10gofpotassiumhydroxidein150mLdeionizedwater.Thismixturewasstirredinanicebathfor30minutestodisintegrategraphiteflakes.Subsequently,10gofK2CO3wasaddedandstirredatroomtemperaturefor2hours.Thenthemixturewasirradiatedwith700Wmicrowaveradiationinadomesticmicrowaveovenfor5minutes.Aftertheirradiation,theproductwasremovedandwashedseveraltimeswithdeionizedwater,thendriedat80℃overnight.Finally,theproductwassubjectedtothermaltreatmentundernitrogenatmosphereat1050℃for2hourstoobtainexpandablegraphite. Characterization:Themorphologyandmicrostructureofexfoliatedgraphitewereexaminedusingascanningelectronmicroscope(SEM).ThecrystalstructureofthematerialwasstudiedusingX-raydiffraction(XRD)analysis. ResultsandDiscussion TheSEMimageoftheas-synthesizedexpandablegraphite(Figure1)showsthatthematerialiscomposedofthinandhighlye