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大连理工大学学报 2014
ComparativestudiesofanodegasdiffusionlayersfordirectmethanolfuelcellsDOI: 10.7511/dllgxb201403005, PP. 291-297 Keywords: directmethanolfuelcells(DMFCs),gasdiffusionlayer(GDL),porosity,masstransfer,methanoldiffusioncoefficient Abstract: Comparativestudiesoffourcommon-usedanodegasdiffusionlayers(A-GDLs)，namelycarboncloth，carbonpaper,carbonpaperbasedonXC-72(inshortXC-72)andGDLmadeofcarbonnanotubes(CNT)fordirectmethanolfuelcells(DMFCs)werecarriedoutanddiscussed.Theresultsofscanningelectronmicroscope(SEM)，mercuryintrusionporosimeter(MIP)andelectrochemicaltestshowthatCNThaslargeporesizedistributioninporesizeof1000-3000nmandthelargesttotalporositycomparedwiththoseoftheotherthree.CarbonpaperandXC-72showdisadvantageousinfluencesoncellperformancesathighcurrentdensity，becausecarbonpaperhasmanylargeporeswhichareunsuitedforwatertransport，whileXC-72hasmanysmallporeswhichareunsuitedforgastransport.Thoughcellwithcarbonclothhasthehighestmethanoldiffusioncoefficient，itshowsalittlelowerperformancethanthatwithCNTduetoitsthickness.Anodepolarization(AP)resultsalsodisplaythatthecellwithCNThastheleastmethanolmasstransferresistance.Asaresult，thecellwithCNTshowsthebestperformancewiththehighestlimitingcurrentdensityandpeakpowerdensityof460mA·cm-2and110mW·cm-2，respectively.
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