LASER-INDUCED BREAKDOWN SPECTROSCOPY
Editedby
JAGDISH P.SINGH
InstituteforCleanEnergyTechnologyandDepartmentofPhysicsandAstronomy, MississippiStateUniversity,Starkville,MS,UnitedStates
SURYA N.THAKUR
DepartmentofPhysics,BanarasHinduUniversity,Varanasi,India
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Contributors
MuhammadSherAfgan StateKeyLabofPower Systems,InternationalJointLaboratoryonLow CarbonCleanEnergyInnovation,Departmentof EnergyandPowerEngineering,TsinghuaUniversity,Beijing,China
K.K.Ayyalasomayajula CenterforInformatics andAnalytics,UniversityofMississippiMedical Center,Jackson,MS,UnitedStates
HalilBerberoglu PhysicsDepartment,AnkaraHacı BayramVeliUniversity,Ankara,Turkey
ChetR.Bhatt NationalEnergyTechnologyLaboratory,U.S.DepartmentofEnergy,Morgantown, WV,UnitedStates
GoncaBilge DepartmentofFoodEngineering,Konya FoodandAgricultureUniversity,Konya,Turkey
AlexanderA.Bol’shakov AppliedSpectra,Inc., WestSacramento,CA,UnitedStates
IsmailHakkı Boyaci DepartmentofFoodEngineering,HacettepeUniversity,Ankara,Turkey
B.Busser GrenobleAlpesUniversityHospital, CHUGA;InstituteforAdvancedBiosciences (InsermU1209/CNRS5309),GrenobleAlpesUniversity,Grenoble,France
BeatriceCampanella AppliedandLaserSpectroscopyLaboratory,InstituteofChemistryofOrganometallicCompounds,Pisa,Italy
DanielDiaz MechanicalandAerospaceEngineeringDepartment,UniversityofFlorida, Gainesville,FL;CollegeofEngineering,University ofArizona,Tucson,AZ,UnitedStates
P.K.Diwakar SouthDakotaSchoolofMines,Rapid City,SD,UnitedStates
KemalEfeEseller ElectricalandElectronicsEngineeringDepartment,AtilimUniversity,Ankara,Turkey
C.Fabre GeoRessourcesLaboratory(UMR7359), UniversityofLorraine—CNRS,Vandoeuvre-lesNancy,France
GhaneshwarGautam FortPeckCommunity College,Poplar,MT,UnitedStates
J.J.Gonzalez AppliedSpectra,Inc.,WestSacramento;LawrenceBerkeleyNationalLaboratory, EnergyTechnologiesArea,EnergyStorageand DistributedResourcesDivision,LaserTechnologiesGroup,Berkeley,CA,UnitedStates
JenniferL.Gottfried CCDCArmyResearch Laboratory,WeaponsandMaterialsResearch Directorate,AberdeenProvingGround,MD, UnitedStates
ChristianL.Goueguel LogiagInc.,Chateauguay, QC,Canada
ManojKumarGundawar AdvancedCentreof ResearchinHighEnergyMaterials(ACRHEM), UniversityofHyderabad,Gachibowli,Hyderabad, Telangana,India
DavidW.Hahn MechanicalandAerospace EngineeringDepartment,UniversityofFlorida, Gainesville,FL;CollegeofEngineering,UniversityofArizona,Tucson,AZ,UnitedStates
S.S.Harilal PacificNorthwestNationalLaboratory, Richland,WA,UnitedStates
RichardR.Hark InstituteforthePreservationof CulturalHeritage,YaleUniversity,WestHaven, CT,UnitedStates
RussellS.Harmon DepartmentofMarine,Earth, andAtmosphericSciences,NorthCarolinaState University,Raleigh,NC,UnitedStates
ChristopherM.Helstern UniversityofTennessee SpaceInstitute,CenterforLaserApplications, Tullahoma,TN,UnitedStates
ZongyuHou StateKeyLabofPowerSystems,InternationalJointLaboratoryonLowCarbonClean EnergyInnovation,DepartmentofEnergyand PowerEngineering,TsinghuaUniversity,Beijing, China
JineshC.Jain NationalEnergyTechnologyLaboratory,U.S.DepartmentofEnergy,Morgantown, WV,UnitedStates
RohitKumar DepartmentofPhysics,Chaudhary MahadeoPrasadDegreeCollege,Prayagraj,Uttar Pradesh,India
JeremieLasue IRAP,Univ.PaulSabatier –CNRS –Obs.Midi-Pyrenees,Toulouse,France
StefanoLegnaioli AppliedandLaserSpectroscopy Laboratory,InstituteofChemistryofOrganometallicCompounds,Pisa,Italy
X.L.Mao LawrenceBerkeleyNationalLaboratory, EnergyTechnologiesArea,EnergyStorageand DistributedResourcesDivision,LaserTechnologiesGroup,Berkeley,CA,UnitedStates
SylvestreMaurice IRAP,Univ.PaulSabatier –CNRS –Obs.Midi-Pyrenees,Toulouse,France
GulabSinghMaurya UltrafastSpectroscopyLab, DepartmentofChemistry,IITKanpur,Kanpur, UttarPradesh,India
DustinL.McIntyre NationalEnergyTechnology Laboratory,U.S.DepartmentofEnergy,Morgantown,WV,UnitedStates
G.Miloshevsky VirginiaCommonwealthUniversity,Richmond,VA,UnitedStates
S.Moncayo Ramo ´ nyCajalHealthResearchInstitute(IRYCIS),Madrid,Spain
V.Motto-Ros LightandMatterInstitute(UMR 5306),Lyon1University—CNRS,Villeurbanne, France
ReinhardNoll Fraunhofer-InstitutfurLasertechnik (ILT);RWTHAachenUniversity,Lehrstuhlfur Lasertechnik(LLT),Aachen,Germany
StefanoPagnotta AppliedandLaserSpectroscopy Laboratory,InstituteofChemistryofOrganometallicCompounds,Pisa,Italy
VincenzoPalleschi AppliedandLaserSpectroscopyLaboratory,InstituteofChemistryofOrganometallicCompounds,Pisa,Italy
UlrichPanne FederalInstituteforMaterials ResearchandTesting(BAM);Departmentof Chemistry,HumboldtUniversityofBerlin,Berlin,Germany
ChristianG.Parigger UniversityofTennessee SpaceInstitute,CenterforLaserApplications, Tullahoma,TN,UnitedStates
JayantaKumarPati DepartmentofEarthandPlanetarySciences,NehruScienceCentre;National CenterofExperimentalMineralogyandPetrology, UniversityofAllahabad,Allahabad,India
FrancescoPoggialini AppliedandLaserSpectroscopyLaboratory,InstituteofChemistryofOrganometallicCompounds,Pisa,Italy
AbhishekKumarRai DepartmentofEarthand PlanetarySciences,NehruScienceCentre, UniversityofAllahabad,Allahabad,India
AwadheshKumarRai LaserSpectroscopy ResearchLab,DepartmentofPhysics,University ofAllahabad,Prayagraj,UttarPradesh,India
PradeepKumarRai DepartmentofNephrology, OpalHospital,Varanasi,India
V.N.Rai LaserPlasmaDivision,RajaRamanna CentreforAdvancedTechnology;Schoolof Physics,DeviAhilyaUniversity,Indore,India
RichardE.Russo AppliedSpectra,Inc.,WestSacramento;LawrenceBerkeleyNationalLaboratory, EnergyTechnologiesArea,EnergyStorageand DistributedResourcesDivision,LaserTechnologiesGroup,Berkeley,CA,UnitedStates
HerveK.Sanghapi AlcornStateUniversity,Lorman,MS,UnitedStates
GiorgioS.Senesi CNR—IstitutoperlaScienzae TecnologiadeiPlasmi(ISTP)—SedediBari,Bari, Italy
BanuSezer DepartmentofFoodEngineering, Hacettepe University,Ankara,Turkey
Sahar Sheta State KeyLabofPowerSystems,InternationalJointLaboratoryonLowCarbonClean EnergyInnovation,DepartmentofEnergyand PowerEngineering,TsinghuaUniversity,Beijing, China
JagdishP.Singh InstituteforCleanEnergyTechnology(ICET);DepartmentofPhysics,Mississippi StateUniversity;JPSAdvancedTechnologyR&D LLC,Starkville,MS,UnitedStates
RajeshKumarSingh InstituteforPlasmaResearch, Gandhinagar,Gujarat,India
DavidM.Surmick UniversityofMassachusetts, Lowell,MA,UnitedStates
SuryaN.Thakur LaserandSpectroscopyLaboratory,DepartmentofPhysics,BanarasHinduUniversity,Varanasi,India
PravinKumarTiwari LaserSpectroscopyResearch Laboratory,DepartmentofPhysics,Universityof Allahabad,Prayagraj,UttarPradesh;Institutefor PlasmaResearch,Gandhinagar,Gujarat,India
MarkandeyM.Tripathi InstituteforCleanEnergy Technology,MississippiStateUniversity, Starkville,MS,UnitedStates
XiongWan ShanghaiInstituteofTechnicalPhysics (SITP),ChineseAcademyofSciences(CAS), Shanghai,China
ZheWang StateKeyLabofPowerSystems,InternationalJointLaboratoryonLowCarbonClean EnergyInnovation,DepartmentofEnergyand PowerEngineering,TsinghuaUniversity,Beijing, China
RogerC.Wiens LosAlamosNationalLaboratory, LosAlamos,NM,UnitedStates
ShunchunYao SchoolofElectricPower,South ChinaUniversityofTechnology,Guangzhou,China
J.Yoo AppliedSpectra,Inc.,WestSacramento,CA, UnitedStates
FangY.Yueh InstituteforCleanEnergyTechnology (ICET);DepartmentofPhysics,MississippiState University;JPSAdvancedTechnologyR&D LLC,Starkville,MS,UnitedStates
LeiZhang StateKeyLaboratoryofQuantum OpticsandQuantumOpticsDevices,Instituteof LaserSpectroscopy,ShanxiUniversity,Taiyuan, China
Preface
Thehistoryoflaser-inducedbreakdown spectroscopy(LIBS)issimilartothehistoryof “spectroscopy”itself.Spectroscopyformally beganin1814,whenFraunhoferrecordedand measuredthedarkspectrallinesinthesolar spectrum;thiswasabout150yearsafterthefirst observationofa“spectrum”bySirIsaacNewton.Ittookanotherfourandahalfdecadesfor KirchhoffandBunsentoestablishthefactthat these“darklines”belongedtoelementsthat producedbrightlycoloredemissionlineswhen fedintotheflameofaBunsenburner.Avariety ofsourcesemittinglinespectra,suchaselectric arcs,sparks,anddischargetubes,weredevelopedtoaccumulateandanalyzethespectral dataforalargenumberofelements.Thesuccess oftheBohrmodelintheoreticallyexplainingthe observedspectrallinesofhydrogenledtothe conceptoftheelectronicstructureofatoms, andanewunderstandingoftheperiodictable emergedinformedbyspe ctraldata.Theinventionofthelaserin1960maybecomparedto thediscoveryofthespectrumbecauseitprovidedatoolforinvestigatingthedynamicsof excitedatomsandmoleculesbymeasurement oftheirtemporaldecay.Soonafteritsinvention,apulsedrubylaserbeamwasfocused ontoametallicsurface,producingasparksimilartothatproducedbetweentwometalrods byanelectricfield.However,fortwodecades aftertheadventoflaser-inducedplasmaemissionspectroscopy,scientificinterestwasmore focusedonthebasicphysicsofplasmaformationandeffortstoreducethebackground continuumassociatedwiththespectrallines. TheacronymLIBSwascoinedbyRadziemski
andcoworkersintheearly1980s;theyplayed amajorroleintheexperimentaldevelopmentofthisversatileanalyticaltechnique. Theplasmaplumeproducedbyasinglelaser pulsefromasamplecanrevealthepresence ofallofitsconstituentatomsbyspectral analysis.LIBSisauniquetechnologythatis capableofprovidingdistinctspectralsignaturescharacteristicofallchemicalspeciesin allenvironments.
Sincethepublicationofthefirsteditionofthis book,therehavebeenmanydevelopmentsin thecomponentsusedinLIBSleadingtoasignificantreductioninthesizeoftheequipment;this andnewstatisticalmethodsofanalyzingthe spectraldatahaveledtomanyindustrialapplications.Alltheseapplicationsdependonthe detectionofatomsinavarietyofcomplexsamples.Oneisremindedofthefamoussuggestion ofRichardFeynmanthatthemostvaluable informationonscientificknowledgeinasingle sentenceusingthefewestwordsis:“Allthings aremadeofatoms.”Inadifferentcontext,Feynmansaid,“Themostremarkablediscoveryinall ofastronomyisthatthestarsaremadeofatoms ofthesamekindasthoseontheearth.”This camemuchbeforeAugust2012whenChemCam,withtheLIBSinstrument,startedexploringthesurfaceofMarsontheCuriosityrover andisstillgatheringspectraldataontherocks andsoilinsearchofevidenceoflifeinthe remotepast.ItisthefirsttimethattheLIBS techniquehasbeenusedonanotherplanet andthishistoriceventhasgeneratedagreatdeal ofenthusiasmamongstudentsandyoung researchersindealingwiththecompositional
analysisofmaterials,includingbiological materials.InadditiontothefundamentalprocessesandunderlyingphysicsofLIBS,thepresenteditionofthebookhas15newchapters containingrecentadvancesinthefield,such asmolecularLIBS,self-calibratedmethods, high-energymaterials,LIBSimaging,foodscience,coal,flame,defense,matrixeffects,LIBS forplanetaryscience,analysisofmedical drugs,andindustrialapplications.Thechapters havebeenarrangedsuchthatthereisaneasy andsmoothprogressionfromfundamentalsto experimentaltechniquesandapplications.
Thepurposeofthisbookistogiveasimple andcomprehensivereviewofLIBS,including recentadvancesinthefield.Itiswellstructured andorganizedinthreebroadsectionsdealing withfundamentals,newtechniques,andapplicationsofLIBS.PartIofthebookcomprisesfive chapters.Thefirstchapterdealswiththetemporalandfocusingpropertiesoflaser,laserproducedplasmas,andthespectralrecording oftheemissionusingspectrographsequipped withcharged-coupleddeviceandintensified charged-coupleddevicedetectors. Chapter2 containsabriefaccountoftheelectronicstructureofatoms,theperiodictable,andselection rulesforradiativetransitions.Intensitiesofspectrallinesandmechanismsofspectralbroadeningaredescribedalongwiththeirrolesinthe determinationoftemperatureandelectrondensityinlaser-inducedplasma. Chapter3 deals with“ablation,”themostsignificantprocessof plasmaplumeformationinLIBS.Itdescribes theexplosivevaporizationofmaterialandits rate,whichdependsonthetypeofmaterial, thelaserwavelength,theambientatmosphere, andthegeometryofthelaserbeam.Asignificant fractionoftheincidentlaserpulseenergyis absorbedintheexpandingplasmaplume,causingtheatomsandionstoreachdifferentstatesof excitationandhencesubsequentopticalemission.Thephysicsoftheseopticalprocesses formsthesubjectmatterof Chapter4,where theoriginsofcontinuumandlineemissionare
discussedtoemphasizethetemporalcharacteristicsofthespectralemission.Thegeometrical shapeoftheplasmaplumeandthetimewindow forLIBSdetectionhavebeendiscussed.Recent developmentsintheoreticalmodelsforthe dynamicsofplasmaplumehavebeendescribed. Theexperimentalsetupconsistingofalaser,the plasmaplume,andaspectrometerformthe contentsof Chapter5.Thetypeofsample(solid, liquid,orgas)anditslocationinthelaboratory orinthefielddemandaspecificarrangementof theexperimentalcomponentsforLIBSdetection.Instrumentsusingopticalfiberfordelivery oflaserpulsesaswellasforthecollectionof emissionfromtheplasmaplumearediscussed alongwithhandheldLIBSsystems.
PartIIofthebookcontainsavarietyofrecent LIBStechniques.Theuseofultrafastlasersfor generationoftheplasmaplumeandthesubsequentdetectionofitsemissionformsthesubject matterof Chapter6.ItalsoprovidesacomparisonofthistechniquewithnanosecondLIBS.The usefulnessoffemtosecondlaserandlaserfilamentationforstandoffanalysishasalsobeen discussed. Chapter7 discussesthetechnique oflaserablationmolecularisotopicspectrometryfortheidentificationofatomicisotopes. DiatomicmoleculesareformedduetorecombinationinaLIBSexperimentandanalysisoftheir emissionspectrarevealsexcitationtemperatures upto104 Kfollowinglaser-inducedoptical breakdown.
PartIIIofthebookembodiesrecentdevelopmentsintheapplicationsofLIBS. Chapter8 dealswithflameandoffgasmeasurements. Chapter9 isabouttheapplicationofLIBStoliquidsampleswherethesignalsaregenerally weakerthaninsolidsandrequireenhancement techniques.Thedifficultiesassociatedwith underwatermeasurementsandtheirpossible solutionshavebeendiscussedalongwithmatrix andpressureeffects. Chapter10 dealswithLIBS applicationtopowdermaterialswidelyusedin industry.Thedetectionofimpuritiesandtrace elementsinpowdersamplesusedintheglass
andpharmaceuticalindustriesisdiscussed.The possibilitiesofusingLIBSforsourcecharacterizationandabundanceassessmentforcritical elementshavebeendemonstrated. Chapter11 containstheresultsofusingLIBSinthechallengingproblemofquantitativeanalysisof slurrysamples.Spectraldatahavebeenanalyzedusingthreemodelsbasedonunivariate calibration,multiplelinearregression,andpartialleastsquareregressioninconjunctionwith anewsamplingmethod,“spin-on-glass.”PortableLIBSsystemsandstandoffdetectionsystems fordefenseapplicationsformthesubjectmatter of Chapter12.Detectionofburiedlandmines andexplosiveresidueonpersonnel,energetic materialcharacterization,anddiscrimination ofchemicalaswellasbiologicalmaterialsare discussedindetail. Chapter13 containsapplicationsofLIBStotheanalysisofmedicaldrugs. ChemometricanalysisoftheLIBSdatasethas showntobeusefulinthediscriminationofdrug sampleswithsimilarelementalcompositions. Thescopeofthistechniqueintheidentification ofcounterfeitmedicinesinthemarketisdiscussed.ApplicationsofLIBSimagingina numberofdiversefieldsarediscussedin Chapter14.Ithasuniquespecificities,such asmicrometric-scaleresolutionwithlimitsof detectionuptoppminmaterialsamples,includingbiologicalmaterials. Chapter15 dealswith theapplicationsofLIBStodifferentfood matricesforthepurposeofdetectingbothadulterationandgeographicalaswellasbiological origin.LIBShasbeenshowntohavegreatpotentialasaprocesscontroltoolinthefoodindustry. TheapplicationofLIBSforanalysisofgeological samplesisdiscussedin Chapter16.Theanalysis ofmoldavitespectraisexpectedtoaidinstudies ofplanetaryanalogs,includingthestudyof impactiteslitteredontheMartiansurface.The characterizationofselecttopsoilsamplessuggeststhatthismethodiscapableofestablishing thecompositionalheterogeneityofsoilsamples. Chapter17 containsthedevelopmentofan experimentalsetuptorecordonlineLIBSspectra
ofplasma-facingcomponents(PFCs)oftheAdityatokamakinIndia.Calibration-freelaserinducedbreakdownspectroscopy(CF-LIBS) hasbeenfoundtobeverysuitableforquantitativeanalysisofthePFCs. Chapter18 dealswith thescopeofLIBSanalysisofhigh-energymaterials(HEMs).Acomparativeinvestigationof fiveHEMsandfivenon-HEMshasbeencarried outtoassesstheimportanceofstatistical methodsfortheiridentification.Theprincipal componentanalysisscoreplotsshowwellseparatedclustersforHEMsandnon-HEMs forthefullspectrumaswellasforsubspectra. Itisconcludedthatitmaynotbenecessaryto recordthefullspectrumforthedetectionof thetwotypesofmaterials.IndustrialapplicationsofLIBSarediscussedin Chapter19,with emphasisontheresearchpublicationsfrom theyears2014to2019.Inviewofinvestigating objectsatdistancesrangingfromafewcentimetersuptoseveralmeters,LIBShasadistinct advantageformonitoringsamplesinaprocess lineevenunderharshindustrialconditions. Studiesinvolvingidentificationofsteelblooms inarollingmill,sortingofalloyedmetalscrap, andrecoveryofvaluablematerialsfromendof-lifeelectronicequipmentarediscussed.The roleofLIBSinexploringplanetaryenvironmentsusingroversisdiscussedin Chapter20. ThefirstextraterrestrialLIBSinstrument,ChemCam,returned700,000spectraandprovided majorinsightsintothegeochemistryandpast historyofMars.ThedesignsofSuperCam, developedbyNASAtoroamthesurfaceofthe redplanetin2121,andtheVenusElemental andMineralogyCameraaredescribedinadditiontoseveralsimilarsystems.LIBSalsohas manyadvantagesforoutersolarsystemstudies wherelighterelementsarelikelytobeobserved onicy,volatile-richmoonsoftheouterplanets. Chapter21 emphasizestheimportanceof providingfastqualitativeandquantitative informationbyLIBSrequiredforcoalwashing, coalblending,aswellascoalcombustionoptimization.Thechallengesonthewaytofull
commercializationandindustrializationofLIBS coalanalysisarediscussedindetail.LIBSiswell suitedfortheanalysisofaerosolparticlesdueto theuniquepointsamplingnatureoflaserinducedplasmasasdescribedin Chapter22. Adetailedtreatmentofthebreakdownprocess isdiscussedintermsofgas-phaseprocesses associatedwithplasmainitiationandpropagationandthefuturecourseofinvestigationinthis challengingareaisindicated. Chapter23 isconcernedwiththefunctioninganduseofhandheld equipmentforLIBS.Thefundamentalconcepts andapplicationsofself-calibratedmethodsfor quantitativeanalysisbyLIBSformsthesubject matterof Chapter24.Thehypothesesthatform thebasisofclassicalCF-LIBSarecritically reviewedanditsevolutioninthelasttwo decadesissummarized.MonteCarloLIBSand extendedC-sigmamethodsappeartobepromisingalternativestostandardCF-LIBS.Ashort reviewofthemainapplicationsofCF-LIBSis givenforsuchsampleswheretheavailability ofmatrix-matchedstandardsisneededfor uni-ormultivariatecalibrationcurves.
Chapter25 looksatthefuturedevelopmentsin LIBStechnology,newmethodsofspectraldata
analysis,andmanyofitsapplicationsin unexploredareas.
Wegratefullyacknowledgethemostvaluable andimaginativecontributionsbytheauthors whosparedtimefromtheirbusyscheduleof teachingandresearchforthisbook.Weare thankfultothemembersoftheInstitutefor CleanEnergyTechnologyattheMississippi StateUniversityandthoseoftheLaserandSpectroscopyLaboratoryattheBanarasHinduUniversityfortheirenthusiastichelpduringthe preparationofthemanuscript.Specialthanks areduetoProfessorDavidL.MontsandProfessorS.B.Raifortheirmanyvaluablesuggestions. SNTisbeholdentoDr.PunamandDr.Vineeta fortakingcareofhishealth,toSudheerand Sangeetaforhelpwiththecomputer,andtolittle LeoandMiaforkeepinghimentertainedwith theirinnocentinquiries.JPSgreatlyappreciates hiswifeShilaSinghforherpatienceandencouragementandhisgrandchildrenDevansh, Shivansh,Arya,andAniyaforamusinghim duringthepreparationofthebook.
JagdishP.Singh SuryaN.Thakur
