Anodic oxidation of formic acid on PdAuIr C-Sb2O5·SnO2 electrocatalysts prepared by borohydride reduction.pdf

第42卷第7期 燃 料 化 学 学 报 VO1．42N0．7 2014年7月 JournalofFuelChemistryandTechnology Ju1．2014 文章编号：0253-2409(2014)07-0851-07 Anodicoxidationofformicacid on PdAuIr／C-Sb205·SnO2 electr0catalystspreparedbyborohydridereduction A．0．Neto，J．Nandenha，R．F．B．DeSouza， G．SBuzzo，J．C．M ．Silva，E．V．Spinac6，M ．H．M ．T．Assumpq~o (InstitutodePesquisasEnerg~ticaseNucleares—IPEN-CNEN／SP，CidadeUniversit(tria，SaoPaulo 05508—900，Brazil) Abstract：PdAuIr／C．Sb，O ·SnO2electrocatalystswithPd：Au：Irmolarratiosof90：5：5，70：20：10nad50：45：5wereprepraedby borohydridereductionmethod．1heseelectrocatalystswerechraacterizde byEDX，X．raydiffraction，trnasmissionelectronmicroscopy andhtecatalytic activitytowardformic acid electro—oxidation in acidmedium investigatedby cyclicvoltammetry (CV)， chroamperometry(CA)nadtestsondirectofrmicacidfuelce1l(D】AFC)at100oC．X—raydiffractogramsofP山 h／C—Sb2O5·SnO2 elcetrocatalystsshowedhtepresenceofPdfccphase．Pd—Aufccalloys。crabonnadATO phases，whileIrphaseswerenotobserved． TEM mi crographsnadhistogramsindicatedhtathtenna oparticleswerenotwelldispersedonhtesupportnadsomeagglomerates． 111ecyclicvoltammetrynadchroamperometrystudiesshowedthatP(uh／C—Sb，O ·SnO，(50：45：5)hadsuperiorperformnace towradofrmicacidelecrto—oxidationat25℃ compraedtoPdAuh／C—Sb2Os·SnO2(70：20：10)，PdAuIr／C．Sb205·SnO2(9O：5：5) na dPd／C．Sb，O ‘·SnO，electrocatalysts．The experimentsin a single DFAFC also showed htatallPdAuIr／C—Sb，O ·SnO， electrocatalystsexhibitde higherperformnace ofrofrmic acid oxidation in comparison wiht Pd／C—Sb，0 ·Sn0，electrocatalysts． howeverPdAuh／C．Sb，0 ·Sn0，(9O：5：5)hadsuperiorperformnace．TheseresultsindicatedhtattheadditionofAunadIrtoPd favorhteelcetro．oxidationofofrmicacid．whichcouldbeattributedtohtebifunctionalmechanism (htepresence