资源描述：
《赵东元Ordered Mesoporous Materials.pdf》由会员上传分享，免费在线阅读，更多相关内容在学术论文-天天文库。
1、DongyuanZhao,YingWan,andWuzongZhouOrderedMesoporousMaterials11IntroductionMaterialsscienceisoneofthemostimportantsubjectsofsciencesandtech-nologiesinthetwenty-firstcentury.Itsimportancehasbeenemphasizedbythegovernmentsviaformulatingtheirnationalpoliciesinthedevelopedcountries,aswel
2、lasmanydevelopingcountries.Newmaterialsnotonlygreatlypromotethedevelopmentsofindustry,agriculture,medicine,environment,aerospace,andinformationscienceandsoon,butmayalsodemonstratesomerevolutionarychangesoftheirformsandnovelfunctions,andtherebybringabouttremen-douschangestohumanlif
3、e.Unlikethetraditionalmaterialssciencedominatedbymetalsandmetallurgy,modernmaterialssciencehasbecomeatypicalinter-disciplinaryfield.Anymajordevelopmentofnewmaterials,forexamplehigh-temperaturesuperconductors,novelcatalysts,manyfunctionalnanomaterials,etc.,requirescollaborationofsci
4、entistsfrommanydifferentdisciplines.Poroussilicatesareahugefamilyofinorganicmaterials,possessingopen-poreframeworksandlargesurfacearea(includingtheinnerandoutersurfaces).BasedonIUPAC,porousmaterialsaccordingtotheporediametercanbeclassifiedintothreecategories:thosewithporediametersl
5、essthan2nmaremicroporous;poresizesbetween2and50nmaremesoporous;andporediametersgreaterthan50nmarecalledmacroporousmaterials.“Nano”isaconceptwiththesizefrom1to100nm;thereforealltheabovethreekindsofporousmaterialscanbedesig-natedasnanoporousmaterials.However,inmostoftheliterature,na
6、noporousmaterialsrefertomesoporousor/andmicroporousmaterials.Conventionalmicroporousmolecularsieveshaveauniformsieve-likeporestructureandlargesurfacearea.Theyareexcellentadsorbents,catalysts,carriers(catalystsupports),ion-exchangeagentsandnanoreactors.Theyhavebeenexten-sivelyusedi
7、nchemical,petrochemical,gasseparationindustries,andotherfields.Thevastmajorityofsuchmaterialspossessperfectatomiccrystalstructures,thatis,thepositionofeachatomintheunitcellisfixed.Forexample,inazeoliteAwithacubic(spacegroupPmm3)structure(unitcellparameterof11.9nm)(seeFigure1.1a),24o
8、fthesiliconandaluminumatomsoccupy
