2011最新纳米粒子的成核及生长机理综述

rXXXXAmericanChemicalSocietyAdx.doi.org/10.1021/cr2001756|Chem.Rev.XXXX,XXX,000–000REVIEWpubs.acs.org/CRNucleationandGrowthofNanoparticlesintheAtmosphereRenyiZhang,*,†,‡,§AlexeiKhalizov,†LinWang,‡MinHu,§andWenXu††DepartmentofAtmosphericSciencesandDepartmentofChemistry,CenterforAtmosphericChemistryandEnvironment,TexasA&MUniversity,CollegeStation,Texas77843,UnitedStates‡DepartmentofEnvironmentalScience&EngineeringandInstituteofGlobalEnvironmentChangeResearch,FudanUniversity,Shanghai200433,China§StateKeyLaboratoryofEnvironmentalSimulationandPollutionControl,CollegeofEnvironmentalSciencesandEngineering,PekingUniversity,Beijing,100871,ChinaCONTENTS1.IntroductionB2.OverviewofVaporNucleationD2.1.NucleationTheoriesandComputationalApproachesD2.1.1.ClassicalNucleationTheoryD2.1.2.KineticTheoriesF2.1.3.MolecularDynamicsandMonteCarloMethodsF2.1.4.DensityFunctionalTheoryG2.1.5.NucleationTheoremG2.2.NucleationExperimentsH2.2.1.AdiabaticExpansionApproachesH2.2.2.DiffusionChamberH2.2.3.LaminarFlowChamberI2.2.4.TurbulentMixingChamberI2.2.5.ContinuousGenerationofNucleatingVaporsfromChemicalReactionsourcesI2.2.6.ComparisonbetweenExperimentalResultsandNucleationTheoriesI3.NucleationofNanoparticlesintheAtmosphereK3.1.AtmosphericMeasurementsK3.1.1.ConcentrationsandSizeDistributionsofAtmosphericNanoparticlesL3.1.2.ChemicalCompositionofAtmosphericNanoparticlesM3.1.3.MeasurementsofChargedandNeutralAtmosphericClustersP3.2.LaboratoryStudiesR3.2.1.BinaryNucleationofH2SO4
H2OR3.2.2.TernaryNucleationofH2SO4
H2OInvolv-ingAmmoniaandAminesT3.2.3.NucleationofH2SO4
H2OAssistedbyOrganicAcidsU3.2.4.NucleationofIodineOxidesW3.2.5.Ion-InducedNucleationX3.2.6.ChemicalComposition,Reactivity,andThermodynamicsofNucleatingClustersY3.2.7.OtherSpeciesAA3.3.TheoreticalandComputationalStudiesAA3.3.1.QuantumChemicalCalculationsAA3.3.2.MolecularDynamicsandMonteCarloSimulationsAD3.4.ParameterizationsofAtmosphericNucleationAF4.GrowthofNanoparticlesintheAtmosphereAG4.1.RoleoftheKelvin(Curvature)EffectinGrowthofNanoparticlesAH4.2.CondensationAI4.2.1.CondensationofSulfuricAcidAI4.2.2.CondensationofLow-VolatilityOrganicsAI4.3.HeterogeneousReactionsAJ4.3.1.AmmoniaAJ4.3.2.AminesAJ4.3.3.AldehydesAL4.3.4.α-DicarbonylsAM4.3.5.AlcoholsAN4.3.6.OtherSpeciesAO5.NumericalTreatmentofAmbientNanoparticleNucleationandGrowthRatesAP5.1.MeasuredNucleationandGrowthRatesAP5.2.CondensationSinkofLow-VolatilityVaporAP5.3.CombinedGrowthIncludingCondensationandIntramodal/ExtramodalCoagulationAP5.4.DerivationofNucleationRatesfromAtmosphericMeasurementsAQ6.SummaryandFutureResearchNeedsARAuthorInformationASBiographiesASAcknowledgmentATGlossaryofAcronymsATReferencesATReceived:May17,2011Bdx.doi.org/10.1021/cr2001756|Chem.Rev.XXXX,XXX,000–000ChemicalReviewsREVIEW1.INTRODUCTIONThisreviewintendstocriticallyassessrecentfindingsrelatedtonucleationandgrowthofatmosphericnanoparticles,withanemphasisontheunderstandingoftheseprocessesatafunda-mentalmolecularlevel.Aerosols(smallparticlessuspendedinair)canbedirectlyemittedintotheatmospherefromprimarysourcesorbeformedintheatmospherethroughnucleationofgas-phasespecies.Aerosolnucleationeventsproducealargefractionofatmosphericaerosols.Newparticleformationoccursintwodistinctstages,1i.e.,nucleationtoformacriticalnucleusandsubsequentgrowthofthecriticalnucleustoalargersize(2
3nm)thatcompeteswithcaptureandremovalofthefreshlynucleatednanoparticlesbycoagulationwithpre-existingaerosols.Nucleationisgenerallydefinedascreationofmolecularembryosorclusterspriortoformationofanewphaseduringthetransformationofvaporfliquidfsolid.Thisprocessischar-acterizedbyadecreaseinbothenthalpyandentropyofthenucleatingsystem(i.e.,ΔH0andΔS0).Hence,althoughthermodynamicallyfavorableaccordingtothefirstlawofthermo-dynamics,(i.e.,exothermic)nucleationishinderedinentropyaccordingtothesecondlawofthermodynamics.Afreeenergybarrier,ΔG(ΔG=ΔH
TΔS0),isofteninvolvedandneedstobesurmountedbeforetransformationtothenewphasebecomesspontaneous.Anothermajorlimitationinthenucleationandgrowthofatmosphericnanoparticlesliesinsignificantlyelevatedequilibriumvaporpressuresabovesmallclustersandnanoparti-cles,alsoknownastheKelvin(curvature)effect,whichconsiderablyrestrictsgrowthoffreshlynucleatednanoparticles.Formationofmolecularclustersoccursthroughrandomcollisionsandrearrangementsofatomsormoleculesoftheexistingphase(Figure1a).Growthofaclustercanberepre-sentedasareversible,stepwisekineticprocess.Afterreachingacriticalsize(thecriticalclusterornucleus),furthergrowthoftheclusterbecomesspontaneous.Ateachstep,formationanddecompositionofaclustercanbedescribedbyfundamentalkineticratetheories.Aclustercanformhomogeneouslywithintheoriginalphaseorheterogeneouslyonvariousirregularities,suchaspre-existingsmallparticlesorions,whichassistinsurmountingthefreeenergybarrierassociatedwithformationofaninterfacebetweenthesmallclusterofthenewphaseandtheoriginalphase(Figure1b).Thelifetimeofclustersisextremelyshort,butsinceaverylargenumberofclustersformanddissociateatanytime,afewcanreachthecriticalsizeandcontinuetogrowsponta-neouslytoformla