对羟基苯甲酸分子吸附在银纳米颗粒上的吸附行为的实验和理论分析

《对羟基苯甲酸分子吸附在银纳米颗粒上的吸附行为的实验和理论分析》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、昆明理工大学硕士学位论文AbstractSurfaceenhancedRamanscattering(SERS)wasdiscoveredbyFleischmanin1974，ithasshownthegreatsuperioritybecauseofitshighsensitivityandhighfluorescentquenching．Ithasbeenwidelyusedinthestudyoftheinteractionofthemoleculeswitllthesurfaceofthesubstrate．How

2、ever,there’restillmanydebatesaboutthemechanismofSERS．SoafurtherstudyonthemechanismisneedediftheSERStechniqueiswantedtobeusedinamorebroadenarea．especiallyintheinthestudyoftheinteractionmechanismofthemoleculeswiththesurfaceofthesubstrateandmolecularorientation．Whent

3、headsorbatesadsorbedonthesubstrate，thecharacteristicsofthesurfaceofthesubstratesmaybevaried，theSERSspectrumofadsorbatesmaybedifferent．Thismakestheanalysesdifficult．Thecommonanalyticalmethodistohypothesizetheadsorptionorientation，geometryconfigurationandadsorptione

4、ssenceofadsorbatesonthesurfaceofsubstratesbasedontheshiftofRamanbands，enhancementorweaknessofintensity．However,sinceSERSisfoundtobeaffectedbymanyfactorssuchasthedifferentSERSsubstrate，surfaceconfiguration，structure，temperatureandevenpHvalueandsoon，thereforethevera

5、cityofsuchguesshasfrequentlytroubledtheresearcherstomakedefiniteconclusions．Andthereliabilityofadsorptionmodelsandrelevanttheorycannotbeexaminedeffectively,whichresultsinmanydifficultiesintheresearchofSERSmechanismandinapplyingtheSERStechnology．Theoretically,thedi

6、fficultyliesintheestablishmentofasimplemodel，whichshouldbeabletodescribethecombinationofsubstrateandtheadsorbedmoleculeproperly,andatthesam．etime，canbeusedtocalculatethevibrationalspectraeasily．Quantumchemically,however,onecantreattheproblemintwodifferentways：thef

7、irstapproachistheperiodicdensityfunctionaltheory(DFT)andthesecondistouseafiniteclustermodelforthesurfacestudied．Inthethesis，thefirstapproachisused．Thecalculationsbasedondensityfunctionaltheory(DFT)havebeenusedinmanyareas，andtheresultsarealsoingreatagreementwiththe

8、experimentalresultsincalculatingvibrationalfrequencies．Intheworkofthethesis，highqualityRalnanspectraofPHBAinsilvercolloidalsolutionandonthinAayerchromat