La1-xCaxMnO3纳米颗粒的制备及氧还原催化性能.pdf

《La1-xCaxMnO3纳米颗粒的制备及氧还原催化性能.pdf》由会员上传分享，免费在线阅读，更多相关内容在行业资料-天天文库。

1、第29卷第8期无机化学学报Vo1．29No．82013年8月CHINESEJ0URNAL0FIN0RGANICCHEMISTRY1617—1625La。Cno3纳米颗粒的制备及氧还原催化性能冯皓杜婧韩晓鹏程方益陈军(先进能源材料化学教育部重点实验室，南开大学化学学院，天津300071)摘要：本文采用溶胶凝胶法制备了一系列不同Ca含量的钙钛矿型氧化物Lal~CMnO：0～0．4)纳米颗粒，X射线粉末衍射及精修、扫描电镜表征显示其相纯度和结晶度高，颗粒平均粒径约40。在0．1o1．L一KOH水溶液中

2、进行的氧还原电催化性能测试显示，LanCan，MnO样品催化活性最高，表观电子转移数接近4，还原电流密度与Pt／C催化剂相当．而催化稳定性优于Pt／C。进一步研究了LatCa~MnO3样品中Mn价态、晶胞参数的改变对氧还原催化活性的影响．结果表明当：0．3时．催化剂中Mn处于混合价态，Mn—O键长适中，最有利于电催化反应。关键词：溶胶凝胶法；钙钛矿；LaCa~MnO3；氧还原；电催化中图分类号：O614．111文献标识码：A文章编号：1001．4861(2013)08．1617—09DOI：10

3、．3969~．issn．1001—4861．2013．00．286Sol-GelSynthesisofPerovskiteLa1CaxMnO3=0—0．4)NanoparticlesforElectrOcatalyticOxygenReductionFENGHaoDUJingHANXiao—PengCHENGFang-YiCHENJun(KeyLaboratoryofAdvancedEnergyMaterialsChemistry(MinistryofEducation)，CollegeofCh

4、emistry，NankaiUniversity，Tianjin300071，China)Abstract：Inthiswork，aseriesofLalCa~MnO3perovskitenanoparticleswerepreparedthroughasol-gelmethodandinvestigatedascatalystsfortheoxygenreductionreaction(ORR)．TheXRD，SEMandTEMcharacterizationdemonstratedhighc

5、rystallinityofthesynthesizedparticleshavingdiametersofabout40nm．ThecrystalstructurewasdeterminedbyRietveldrefinement，indicatingvariationofthelatticeparameterswiththeamountofsubstitutedCa．Theelectrocatalyticpropertiesofthesampleswerestudiedusingrotati

6、ng—diskandrotatingring-diskelectrodetechniquesinKOHaqueoussolution．Investigationsonthecomposition—performancerelationshipofLa1CalMnO3perovskitesrevealedthatmixedMnvalenceandmediumMn．ObondlengthfavoredtheORRelectrocatalysis．AmongtheLa1Ca~MnO3series，La

7、o7CaoMnO3exhibitedoutstandingORRactivity，enabledan．3apparent4-electronpathwayandshowedsuperiordurabilitycomparedtothebenchmarkcarbon-supportedPtnanoparticles．Furthermore，metal—aircellsassembledwithLao7Ca0_3MnO3coulddeliverhighchargeanddischargecapaci

8、tywithfiatplateaus．TheconsiderablecatalyticperformancesofLa1CaxMnO3nanoparticlesindicatetheirpromisingapplicationaslow-costandhigh-abundancecatalystsinalkalinefuelcellsandmeta1．airbatteries．Keywords：sol-gelsynthesis；perovskite；La1Ca~MnO3；oxygenreduct