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1、DongyuanZhao,YingWan,andWuzongZhouOrderedMesoporousMaterials11IntroductionMaterialsscienceisoneofthemostimportantsubjectsofsciencesandtech-nologiesinthetwenty-?rstcentury.Itsimportancehasbeenemphasizedbythegovernmentsviaformulatingtheirnationalpoliciesinthedevelopedcountries,aswel
2、lasmanydevelopingcountries.Newmaterialsnotonlygreatlypromotethedevelopmentsofindustry,agriculture,medicine,environment,aerospace,andinformationscienceandsoon,butmayalsodemonstratesomerevolutionarychangesoftheirformsandnovelfunctions,andtherebybringabouttremen-douschangestohumanlif
3、e.Unlikethetraditionalmaterialssciencedominatedbymetalsandmetallurgy,modernmaterialssciencehasbecomeatypicalinter-disciplinary?eld.Anymajordevelopmentofnewmaterials,forexamplehigh-temperaturesuperconductors,novelcatalysts,manyfunctionalnanomaterials,etc.,requirescollaborationofsci
4、entistsfrommanydifferentdisciplines.Poroussilicatesareahugefamilyofinorganicmaterials,possessingopen-poreframeworksandlargesurfacearea(includingtheinnerandoutersurfaces).BasedonIUPAC,porousmaterialsaccordingtotheporediametercanbeclassi?edintothreecategories: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,andother?elds.Thevastmajorityofsuchmaterialspossessperfectatomiccrystalstructures,thatis,thepositionofeachatomintheunitcellis?xed.Forexample,inazeoliteAwithacubic(spacegroupPmm3)structure(unitcellparameterof11.9nm)(seeFigure1.1a),24o
8、fthesiliconandaluminumatomsoccupy
