Insertion of Al 2 O 3 in Zinc Metaphosphate Glasses New Insights from 1D 2D Solid State NMR Published as part of The Journal of Phys

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pubs.acs.org/JPCCArticleInsertionofAl2O3inZincMetaphosphateGlasses:NewInsightsfrom1D/2DSolidStateNMRPublishedaspartofTheJournalofPhysicalChemistryvirtualspecialissue“HellmutEckertFestschrift”.GrégoryTricot*CiteThis:J.Phys.Chem.C2021,125,9210−9218ReadOnlineACCESSMetrics&MoreArticleRecommendationsABSTRACT:InsertionofAl2O3inthewidelyusedzincmetaphosphateglassesisinvestigatedinthiscontributionthankstoa1D/2DNMRprotocol.Glassesformulatedinthe(50−x/2)ZnO−xAl2O3-(50−x/2)P2O5compositionlinewereanalyzedat9.4and18.8TtodeterminehowAlatomsmodifytheglassnetwork:(i)1D27AlMASNMRandDQ−SQNMRspectrawererecordedathighfield(18.8T)todeterminethe[x]AlspeciationandtodetectthepresenceofAl−O−Allinkages;(ii)1D31PMASNMRwererecordedat18.8Tandanalyzedwiththehelpof2D27Al(31P)HMQCmapsinordertoprovideefficientandtrustfulnumberingandidentificationofallthephosphatespeciespresentintheglassnetwork;(iii)inadditiontothese2Dqualitativeexperiments,quantitative27Al(31P)REDORNMRexperimentswereperformedat9.4Ttoquantifythe27Al/31PdipolarinteractionandtodeterminethenatureoftheAl(OP)groups.mAltogether,thesetofdataalloweddescribingthelocalandintermediatelengthscalestructuresofthezincaluminophosphateglasses.Themodelwasthenusedtoexplainthenonlinearglasstransitiontemperaturemodificationsobservedforthissystem.1.INTRODUCTIONdifferentaluminateandphosphatebuildingblocksinteractAluminophosphateglasseshavebeenwidelystudiedsincethetogethertocreatethedisorderedglassnetwork.SolidstateNMR1940swhenKreidlreportedthatAl2O3additions(evenatlowalsoappearedtobeaveryefficienttoolforthistypeofanalysisamounts)significantlyimprovethechemicaldurabilityofthankstothenumerouscorrelationtechniquesthatcanbeusedstandardphosphateglasses.1−21Thistypeofglassappearedtoanalyzethespatialproximity(dipolarbasedNMRsequences)DownloadedviaBUTLERUNIVonMay16,2021at11:21:22(UTC).thusasverypromisingsystemsandwereusedinmanytechnicalorthechemicalconnectivity(scalarbasedNMRsequences).2−8SuchcorrelationNMRtechniqueshavebeenwidelyappliedtoapplications.InordertounderstandhowAl2O3additions12,13,16−18improvetheglasscharacteristicsanddurability,manystudiesalkalialuminophosphateglasses,butthereis,totheweredevotedtothestructuralcharacterizationofthistypeofbestofourknowledge,onlyaveryfewnumberofpublicationsSeehttps://pubs.acs.org/sharingguidelinesforoptionsonhowtolegitimatelysharepublishedarticles.glass.ItisnowclearlyestablishedthatPatomsadoptadedicatedtothestructuralcharacterizationofdivalentoxidetetrahedralconfigurationwhereasAlatomscanbefoundunderaluminophosphateglassesby1D/2DNMR.19Inthispaper,wefour-,five-,orsix-foldcoordinatedunits(denotedinthechoosetoinvestigatezincaluminophosphateglassesbecausefollowingas[4]Al,[5]Al,and[6]Al).Tocharacterizethelocalthissystemhasbeenusedasbasedformulationtodeveloporders,solidstate1Dmagicanglespinningnuclearmagneticmaterialsinvolvedinmanystrategictechnicalapplica-9−15resonance(MASNMR)hasproventobeavaluabletooltions.8,11,20,21especiallyforaluminumatoms.1D27AlMASNMRexperimentsAcombinationof1D/2DNMRsequenceswasusedinthisproducespectrawithseparatedregionscorrespondingto[4]Al,studytounderstandhowAlatomsalterthestructureofzinc[5]Al,and[6]Al.Detectionandquantificationcanthusbeeasilymetaphosphate(50ZnO−50P2O5)glasses.ThelocalorderofAldoneespeciallywhentheexperimentsareperformedathighfield.1D31PMASNMRhasalsobeenwidelyusedtoprovideinformationabouttheQnspeciation(wherenisthenumberofReceived:November30,2020connectedphosphorus).However,whilethistechniqueisRevised:April10,2021particularlyefficientfortheanalysisofstandardbinaryPublished:April21,2021phosphate,the31PNMRspectraofaluminophosphateglasses10,13−15arecomposedofverybroadspectracomplextoanalyze.Beyondthislocalorder,itisalsocrucialtounderstandhowthe©2021AmericanChemicalSocietyhttps://doi.org/10.1021/acs.jpcc.0c107239210J.Phys.Chem.C2021,125,9210−9218

1TheJournalofPhysicalChemistryCpubs.acs.org/JPCCArticleatomswasfirstanalyzedusinghighresolution1D27AlNMRGlasstransitiontemperaturesweredeterminedbyDifferentialspectrarecordedathighfield(18.8T).PresenceofAl−O−AlScanningCalorimetry(DSC)usingaSETARAMDSC131bondswastracedusingthe1Dversionofthedoublequantum−device.Theheatingprogramwasappliedto30−50mgofglass22simplequantum(DQ−SQ)NMRcorrelationsequencefromroomtemperatureto650°Cwithaheatingrateof10°C/(Figure1a).Thephosphatenetworknatureandorganizationmin.TheTgvaluesweredeterminedattheonsetoftheendothermiceffect,andtheestimatederrorisassumedtobe±3°C.Mostofthe27Aland31PMASNMRexperimentswererecordedat208.5and323.9MHz,respectively,ona18.8TBrukerspectrometer,witha3.2mmprobeheadoperatingataspinningfrequencyof20kHz.The27AlMASNMRexperimentswereacquiredwitha1μspulselength(correspondingtoaπ/10flipangle),512−1024transientsandarelaxationdelay(rd)of1s.The31PMASNMRspectrawereobtainedwitha1.7μspulselength(correspondingtoπ/4flipangle),16−32transients,andardof300s.Alltherdwereoptimizedandallowedforquantitativemeasurements.The27Aland31Pchemicalshiftswerereferredto0ppminrespecttoliquidAl(NO3)3andH3PO4solutions,respectively.The27Al/27Alspatialproximitywas22investigatedwiththeDQ−SQNMRsequence(Figure1a).1D27AlDQ−SQNMRexperiments,showingAlatomsinvolvedinclosespatialproximitywithotherAlatoms,wereacquiredwithπ/2pulselengthof9μs,2048−4096transients,ardof2s,anda1600μsexcitationandreconversiontimesBR21pulse2scheme.22The27Al(31P)J-HMQCNMRexperiment23(Figure1b)wasperformedat18.8Twithπ/2pulselengthsof9and3.5μsfor27Aland31P.The2Dspectra,showingchemicalconnectivitybetweenthePandAlatomsthroughP−O−Albonds,wereacquiredunderrotor-synchronizedconditionswithFigure1.CorrelationMASNMRpulsesequencesusedinthisstudy:1024×20acquisitionpoints,1024−22528transients,ardof0.5(a)27Al1DDQ−SQ,(b)27Al(31P)HMQC,and(c)27Al(31P)s,andanoptimizedechodelayof6ms,inagoodagreementwithREDOR.262731arecentpublication.TheAl(P)D-HMQCexperi-24,25ments,showingspatialproximitybetweenthePandAlwereinvestigatedwith1D31PMASNMRexperiments.The1Datoms,wereperformedat18.8Twithsimilaracquisition31PNMRspectradecompositionsweresupportedby2Dparametersexceptfortheechodelay.InthisdipolarbasedNMR2731sequence,theheteronuclearcoherencesarecreatedthroughtheAl/PmapsshowingthePatomsinvolvedinthemixedAl−applicationofanoptimized1msSR42pulseblocksonthe31PO−Plinkages.12,13,15These2Dmapswereeditedwiththe1channel.TocompletethishighfieldNMRcharacterization,theHeteronuclearMultipleQuantumCoherence(HMQC)NMR273127312324,25Al/Pinteractionwasquantifiedat9.4TusingtheAl(P)techniqueinboththescalar(Figure1b)anddipolarversions.Finally,the27Al(31P)RotationalEchoDOubleREDORNMRexperiment(Figure1c).Inthissequence,afirstsignal(calledS)obtainedfromstandard27AlspinechoResonance(REDOR)NMRtechnique(Figure1c)wasapplied0tocharacterizetheAl(OP)mconfigurationsinthehighestAl2O3experimentiscomparedtoasecondsignal(calledS)obtainedbyasimilar27Alspin−echosequencedisturbedbythecontentglass.Altogetherthissetof1D/2DNMRdataallowsapplicationofπ-pulsesonthe31Pchanneleveryhalfandfullbuildingastructuralmodelandcontributestoabetterunderstandingofthenonlinearevolutionoftheglasstransitionrotorperiod.Theevolutionofthenormalizeddifference((S0−temperature(Tg)observedinthissystem.S)/S0=ΔS/S0)versusthecompleteechodelay(denotedasNTr)canbeusedtoquantifythedipolarinteractionusingthe2.EXPERIMENTALSECTIONfollowingequationdefinedinthemultispinsystemsapprox-27Glasseswerepreparedalongthe(50−x/2)ZnO−xAl2O3−(50−imation(ΔS/S0<0.2).x/2)P2O5compositionlineusingthestandardmelt-quenchingΔS42method.Materialswereobtainedfrommixturesofreagentgrade=··2(NTr)M2ZnO,Al(OH)3,and(NH4)2HPO4thoroughlymixedandplacedS03πinaPt−Aucrucible.Thebatcheswerefirstheattreatedfromroomtemperatureto600°Cwithaslowheatingrateof1°/minTheM2values(VanVlecksecondmoment)canthenbeusedtoremoveNH3andH2Oandwerethenmeltedat1050−todeterminethenumberofPatomssurroundingtheAlatoms.1150°Cduring20minbeforebeingquenchedbydippingtheMoreinformationaboutthissequence(andalltheREDORbottomofthecruciblesinwater.Meltingtimesandtemper-derivedNMRtechniques)usedtodeterminethenatureofatureswereoptimizedtolimitP2O5volatilizationandtoP(OX)aandX(OP)bstructuralgroups(X=Al,B)formanymaintaintheoverallglassweightlossunder3%.Thesampleswillalumino-andboro-phosphatebasedsystemscanbefoundinrefsbedenotedwithxinthefollowingwithxbeingtheAl2O316and28−32.Inourexperiments,thesetofdatawasacquiredatν=12.5kHzwith16and10μsπpulselengthsfor27Alandcontentofthe(50−x/2)ZnO−xAl2O3−(50−x/2)P2O5com-rotpositions.31P,256transients,andardof2s.9211https://doi.org/10.1021/acs.jpcc.0c10723J.Phys.Chem.C2021,125,9210−9218

2TheJournalofPhysicalChemistryCpubs.acs.org/JPCCArticleTable1.GlassPreparationParametersandGlassTransitionTemperatures(Givenas±3°C)molarcomp./mol%meltingprocedurex/mol%ZnOAl2O3P2O5T/°Ct/min(Δm/m)/%Tg/°C0500501100201.54250.549.750.549.751100202.04322.548.752.548.751150201.04553.7548.123.7548.121150201.5465547.5547.51050200.54607.546.257.546.251050201.0460104510451050201.5457Inthefollowing,thestandardQnnotation(wherenisthedecomposedusingtheCzjzekmodel(Figure3a,dottednumberofbridgingoxygens)usedforstandardphosphatelines).34Thedifferent[x]Al(x=4,5,6)relativeproportionsglasses,willbereplacedbytheQnnotationwherenisthemAldeducedfromthedecompositionsarereportedinFigure4a,numberofconnectedphosphorusandmthenumberofaccompaniedbytheaveragecoordinationnumber(Figure4b).connectedaluminum.Progressivedecreaseofthealuminumcoordinationstateisindicatedthroughthedecreaseof[6]Alandincreaseof[4]Al3.RESULTSspecies.Thecompositionaldomainwhere[6]Alisthedominatingspeciesisverynarrowsince[4]AlbecomestheTransparentglasseswereprepareduptothex=10composition.Theoptimizedmeltingtemperatures,times,andweightlossesmostimportantconfigurationforAl2O3≥3.75mol%sample.AsarereportedinTable1.HigherAl2O3amountsrequiremeltingindicatedbefore,thealuminumaveragecoordinationnumbertemperaturesabove1300°C.Fortheseformulations,theweightdecreasesallalongthecompositionline(Figure4b).Thisnumber(=4*%[4]Al+5*%[5]Al+6*%[6]Al)experiencesastronglossesarehigherthan8%.Theglasscompositionsdonotbelongtothe(50−x/2)ZnO−xAl2O3−(50−x/2)P2O5compositionandamilddecreaseinthe0

3TheJournalofPhysicalChemistryCpubs.acs.org/JPCCArticleFigure3.27Al(a)and31P(b)MASNMRspectraobtainedat18.8TonthexAlO−(50−x/2)ZnO−(50−x/2)PO.The27AlMASNMRspectraare232534displayedwithrepresentativedecompositionsusingtheCzjzekmodel.Figure4.[x]Alrelativeproportions(a)andaveragecoordinationnumber(b)evolutionsinthexAlO−(50−x/2)ZnO−(50−x/2)PO.2325Figure5.(a)1Dfiltered27AlDQ−SQMRspectra;(b)27Al(31P)REDORNMRdataobtainedonthe[4]Alsiteofthex=10sample.AlatomsandPonlysurroundedbyPandZnatoms,asHMQCsequence,thatisonlysensitivetothechemical12−15previouslydoneinalkalialuminophosphatesystems.Theconnectivity.Asalreadyobservedforborophosphate23−2529,352DmapsobtainedwiththeHMQCtechniquesareglasses,thescalaranddipolarHMQCsequenceswithreportedinFigures6and7,accompaniedbythe2D31Pandoptimizedparametersprovidesimilarcorrelationschemes.Our27Alprojectionsintheverticalandhorizontalaxis.Mostofthedipolar2Dmaps(thatrequires3htoberecordedinsteadof9h2Dmapspresentedherearebasedonthedipolarmediatedincaseofthescalarmap)canthusbesafelyusedinthesequenceandtheobservedcorrelationsignalsarethusthediscussion.The2DmapsofFigure7presentthreetypesofsignaturesofshortP/Alspatialproximity.TherelevanceofcorrelationsignalindicatingthatthethreealuminumspeciesmixinterpretingthisshortdistanceintermsofchemicalconnectivitywithPatomstocreatemixedlinkages.InterestingfeatureisisverifiedinFigure6wherethedipolarmapobtainedonthex=providedbythe2Dmapobtainedonthex=2.5sample(Figure7.5samplebytheD-HMQC(Figure6a)iscomparedtoascalar7a)withcleardifferencebetween2Dcorrelationsignalsmap(Figure6b)obtainedonthesamesamplebythestandardJ-involving[4]Aland[5/6]Alspecies.Forthatcompositiononly,a9213https://doi.org/10.1021/acs.jpcc.0c10723J.Phys.Chem.C2021,125,9210−9218

4TheJournalofPhysicalChemistryCpubs.acs.org/JPCCArticleFigure6.2Ddipolar(a)andscalar(b)27Al(31P)HMQCmapsobtainedonthex=7.5sample.Figure7.2Ddipolar27Al(31P)HMQCmapsobtainedonthex=2.5(a),5(b),7.5(c),and10(d)samples.The2Dmapsaredisplayedwith27Aland31Pprojectionsinthehorizontalandverticaldimensions.differencecanbeobservedbetweenPconnectedtothelow2DmapofFigure7a)butforhigherAl2O3contents,the2Dcoordinationstate([4]Al)andPconnectedtotheothermapsonlyshowsignificantcorrelationwithtetra-coordinatedaluminumspecies([5]Aland[6]Al).However,toavoidanyaluminumatoms.TheobtainedNMRparameterswerethenusedasinputdatatohelpandguidethe1D31PMASNMRoverinterpretation,thesetwocontributionswillbegatheredtogetherinauniqueprojection.The31P2Dmapprojections,spectradecomposition(Figure8b).Inthesefive-componentsshowingthePatomsinvolvedinP−O−Allinkages,aremodel,thetwospecieshighlightedbythe2Dcorrelationstudy(highlightedingray)areaccompaniedbythreecomponentsdisplayedinFigure8a.ThespectraweredecomposedusingaminimumnumberofcomponentsinordertoobtainNMRextractedfromthebinaryZnO−P2O5systemrepresentingthestandardQ3,Q2,andQ1units.Itisnoteworthythattheratioparameters(chemicalshiftandfullwidthathalf-maximum)of11betweentheQ1AlandQ2Alsignalsaredifferentbetweentheeachmixedspecies.Alltheprojectionscanbedecomposedusingcorrelation(Figure8a)andthestandard1DMASNMR(Figureatwo-componentsmodel.Thechemicalshiftvaluesofthesetwo8b)spectrabecauseofthedifferentnumberofconnectedAl1componentsallowustoassignthesesignalstoQ1Al(aPatoms.IncreaseofthemixedQ1andQ1speciessignalsat1Al2AlconnectedtooneotherPandoneAlatom)andQ1species(a2AltheexpenseofsignalsfromthebinarysystemindicatesthatthePconnectedtooneotherPandtwoAlatoms).Itcanbenetworkprogressivelyshiftsfromapurephosphatetoamixedobservedthatforthex=2.5sample,thePareconnectedtobothaluminophosphatenetwork.Relativeproportionsbetweenthese[5,6]Aland[4]Alatoms(asseeninthehorizontalprojectionofthefivespeciesaredisplayedinFigure9andalltheNMRdataare9214https://doi.org/10.1021/acs.jpcc.0c10723J.Phys.Chem.C2021,125,9210−9218

5TheJournalofPhysicalChemistryCpubs.acs.org/JPCCArticleFigure8.31Pprojectionsofthe2Dmapsaccompaniedbydecomposition(a)and1D31PMASNMRdecompositionusingthedataobtainedinparta(ingray)(b).4.DISCUSSIONTheglassespresentedherewereobtainedinthexAl2O3−(50−x/2)ZnO−(50−x/2)P2O5systemuptox=10mol%.BatchescontaininghigherAl2O3contentsweremeltedandquenchedbutexperiencedsignificantweightlosses(>8%)duetothehightemperatures(>1300°C)usedforthemeltingstage(evenafteroptimization).TheseglasscompositionsdonotmatchthexAl2O3−(50−x/2)ZnO−(50−x/2)P2O5lineandarenotreportedinthispaper.Whilethecompositionalrange(0−10mol%)reportedforourzincsystemmayappearnarrowcomparedtotheonereportedintheliteraturefortheAl2O3−9,36NaPO3line(uptox=27.5mol%),TgofourzincFigure9.RelativeproportionsoftheQnandQnspeciesallalongthealuminophosphatesamplespresentsatwo-domainevolutionmAlcompositionline.Therelativeproportionsaregivenwithanerrorofwithafirstincreasefollowedbyaplateau,asalreadyreportedfor9,12,36±2%.thesodium(andotheralkali)aluminophosphateglasses.However,theincreaseobservedinourcaseisonlylimitedto40°C(from425to465°C),farfromtheincreaseof200°CgatheredinTable2.ThedatashowastrongdecreaseoftheQ2observedintheAlO−NaPOsystemwhen12.5mol%of233sitesthatareprogressivelyreplacedbymixedQ1andQ1AlOareinserted.9,361Al2Al23species.Forglassescontainingmorethan7.5mol%ofAl2O3,theInsertionofAl2O3stronglyaltersthestructureoftheglassphosphatenetworkisdominatedbythetwomixedspecies.networkasindicatedbythe1D27Aland31PMASNMRTable2.31PNMRParameters:ChemicalShift(δ,±0.1ppm),FullWidthatHalf-Maximum(FWHM,±0.2ppm)andRelativeisoaProportions(rel.prop.,±2%)x/mol%Qnδ/ppmfwhm/ppmrel.prop./%Qnδ/ppmfwhm/ppmrel.prop./%isoiso0Q3−42.311.42Q2−30.911.296Q1−11.98.622.5Q1−23.2(−23.3)13.7(13.5)13Q3−40.511.671AlQ1−35.1(−35.1)15.2(15.0)4Q2−31.011.6682AlQ1−12.010.285Q1−22.3(−21.9)11.5(12.4)22Q3−39.811.5121AlQ1−31.1(−30.8)11.4(12.9)12Q2−31.812.2432AlQ1−12.710.3117.5Q1−22.4(−22.5)11.8(11.5)26Q3−39.511.5131AlQ1−29.9(−30.5)11.2(12.0)23Q2−31.512.2262AlQ1−12.610.51210Q1−21.8(−22.1)11.7(11.7)30Q3−39.411.5101AlQ1−29.5(−29.6)11.4(11.0)26Q2−31.511.9212AlQ1−12.110.513aTheNMRparametersdeducedfromthesimulationsofthe31Pprojectionsofthe27Al/31P2Dmapsarereportedintobrackets.9215https://doi.org/10.1021/acs.jpcc.0c10723J.Phys.Chem.C2021,125,9210−9218

6TheJournalofPhysicalChemistryCpubs.acs.org/JPCCArticleexperiments(Figure3).Asalreadyobservedinalkali-containingreactivitywiththeformationofQ1andQ1species,i.e.1Al2Alsystems,AlatomsenterintothenetworkashighlycoordinatedphosphateconnectedtooneotherPandone(ortwo)Alatoms.[6]Alunitsthatarethenconvertedinto[4]AlspecieswhenAlO23Aspreviouslyobservedinpotassiumaluminophosphateglasses,12,13[5]Aland[6]Alproducesimilarcorrelationsignalsincreases.However,cleardifferencecanbenoticedwhentheoverallAlcoordinationiscomparedtothevaluesmeasuredoninthe2Dmaps(Figure7,x=2.5)suggestingthatthesetwohigh9,36theAl2O3−NaPO3system.AsshowninFigure10,whileancoordinationstateunitsplayasimilarstructuralrole.Figure9showsthattheformationofthetwomixedspeciesQ1and1AlQ1occursattheexpenseoftheQ2moieties.Thatlatterunit2Alpresentsthehighestrelativeproportionuptox=7.5beforebeingoutnumberedbyQ1andQ1units.Itisalso1Al2AlnoteworthythatthisAl/PmixingproducesareorganizationofthepurephosphatenetworkwithanoticeableincreaseofQ3andQ1speciesindicatingthatAlinsertionpromotestheQ2disproportionation.AquantitativedescriptionofthephosphatenetworkmodificationsisproposedinFigure11awiththeevolutionofthenumberofP−O−AlandP−O−Plinkages.ThesetwonumbersarecalculatedfromthetotalnumberofthePatomsintheglassformulationsandfromtheQnmAlassignment,n(andm)beingusedtocalculatedthenumberofP−O−P(andP−O−Al)linkages.ThenumberofP−O−PFigure10.AveragecoordinationnumberofAlversustheAl2O3contentbondsdecreasesasexpectedfromthereplacementofQ2byinZnO-andNa2O-[10]aluminophosphatesystems.11Q1AlandQ2Alspecies.However,P−O−Premainsthedominanttypeoflinkageupto7.5mol%ofAl2O3.TheabruptchangeinslopeoccursinthesodiumaluminophosphatenumberofP−O−Albondsincreasesinalinearwayinthe0≤xsystemforaAl2O3contentof15mol%,thishigh-to-low≤7.5mol%rangebeforeexperiencingalessintenseincrease.coordinationstatechangeseemstooccuratverylowAl2O3ThislessintenseincreaseoftheP−O−Allinkagenumbermayamounts(2.5mol%)inthezincaluminophosphatematerials.indicatethatAlatomsdonotpreferentiallymixwithPinthisThisdifferenceintheAlcoordinationalsosuggestadifferentcompositionalrange.ThisinformationissupportedbyFigureimpactonthephosphatenetworkstructuredependingonthe11bwherethenumberofP−O−AllinkagescalculatedfromournatureofthecounterionassociatedwiththemetaphosphateQnassignmentisplottedversusthenumberofAl−O−PmAlcomposition.bondscalculatedfromtheoverallAlcoordinationnumberandTheformationofP−O−AllinkagesisclearlyhighlightedbybyassumingthatAlisonlyconnectedtoPatoms.Bothvaluesthemodificationsofthe31PMASNMRspectra(Figure3b)andareinagoodagreementinthe0≤x≤7.5rangebutshowbythecorrelationsignalsobservedinthe2Dmaps(Figures6significantdisagreementforthex=10composition.Forthatand7).InsertionofAlinthephosphatenetworkleadstoP/Alsample,thenumberofAl−O−PbondscalculatedfromtheFigure11.EvolutionofthenumbersofP−O−PandP−O−Allinkages(a).ComparisonbetweenthenumbersofP−O−AlandAl−O−Pbonds(assumingthepresenceofAl(OP)groups)(b)andnumberoflow([4]Al)andhigh([5]Al+[6]Al)coordinationAlspecies(c).x9216https://doi.org/10.1021/acs.jpcc.0c10723J.Phys.Chem.C2021,125,9210−9218

7TheJournalofPhysicalChemistryCpubs.acs.org/JPCCArticlecomposition(85.8±1)ishigherthantheonecalculatedfromtheQ2units,(ii)anoticeableQ2disproportionation,and(iii)ourNMRassignment(73.8±4).ThisalsomayindicatethatAltheformationofQ1andQ1species.OurcorrelationNMR1Al2AlarenotjustattachedtoPingoodagreementwiththesignalstudyallowcharacterizingthepassagefromapurephosphate(xobservedinthe27AlDQ−SQNMRspectrum(Figure5a),=0)toamixedaluminophosphate(0≤x≤7.5)networkwhichsuggeststheexistenceofsomeAl−O−Allinkages,andthroughthenumberingofP−O−PandP−O−Allinkagesandwiththe27Al(31P)REDORresult(Figure5b),whichindicatestheiroppositeevolutionwiththeintroductionofAlOinthe23thatAlisnotonlyconnectedtoPatoms.Therefore,webelieveformulations.At10mol%ofAlO,27AlDQ−SQexperiment23thatAlpreferentiallymixeswithPatomstocreateP−O−Aland27Al(31P)REDORdatasuggestthepresenceofAl−O−Albondsinthe0≤x≤7.5rangeleadingtothepassagefromapurelinkages.TheTgnonlinearevolutionmeasuredinthissystemphosphatetoamixedaluminophosphatenetwork.Then,newwasfinallyrelatedtothenumberof[5/6]Alspeciessuggestingtypeoflinkageappearsabove7.5mol%withthepossiblethatTgiscontrolledbytheoverallnetworktopologyandnotbyformationofAl−O−Albondsintheglassnetwork.MixingthenumberofP−O−PandP−O−Allinkages.betweenZnandAlhasnotbeenhighlightedherebutcanalsobeassumedinthislatterdomain.Znsegregationleadingtothe■AUTHORINFORMATIONformationofZn−O−ZnbondscouldalsobepartofthisCorrespondingAuthorstructuralreorganizationoccurringathighAl2O3contents.GrégoryTricot−CNRS,UMR8516-LASIR-LaboratoiredeUnfortunately,noclearinformationabouttheexactroleofzincSpectrochimieInfrarougeetRaman,UniversitéLille,F-59000atomswasprovidedbyour67ZnNMRstudy(notpresentedLille,France;orcid.org/0000-0002-5996-7158;here).Inbinaryzincphosphateglasses,zincisknowntobehexa-Email:gregory.tricot@univ-lille.frcoordinatedatlowamountsandtetra-coordinatedforhigherZnOcontents.37ThischangeintheZncoordinationstateCompletecontactinformationisavailableat:modifiesthenetworkorganizationandthemacroscopichttps://pubs.acs.org/10.1021/acs.jpcc.0c10723propertiesofbinaryphosphate,anditislikelythatsucheffectoccursinourzincaluminophosphateglasses.NotesInterestingconclusioncanalsobederivedabouttheTTheauthordeclaresnocompetingfinancialinterest.gevolution.AsshowninFigure2,theabruptchangeintheslopeoftheTgevolutionoccursatx=3.75withafirstincrease■ACKNOWLEDGMENTS(forx≤3.75)followedbyaplateauforhigherAl2O3contents.FinancialsupportfromtheIR-RMN-THCFR3050CNRSforNosingularitycanbeobservedinpartsaandbofFigures11atxconductingtheresearchisgratefullyacknowledged.Anonymous=3.75mol%,suggestingthatTgisnotgovernedbythetypeorreviewersareacknowledgedfortheircommentsandremarksnumberoflinkageinthissystem.Theoverallnetworktopologythatsignificantlyimprovedthequalityofthearticle.isalsodirectlyrelatedtothePatomsconnectivity.ThislatterisstronglymodifiedwiththeAl2O3introductionandthenetwork■REFERENCESevolvesfromQ2unitstoamixtureofQ1andQ1species.1Al2Al(1)Kreidl,N.J.;Weyl,W.A.PHOSPHATESINCERAMICWARE:ThesetwolatterspeciescreatetwoandthreelinkagesIV,PHOSPHATEGLASSES*.J.Am.Ceram.Soc.1941,24,372−378.respectivelyandcouldthusbeconsideredaspseudoQ2and(2)Wilder,J.A.GlassesandglassceramicsforsealingtoaluminumQ3unitsandtheirpresenceshouldimpacttheTevolution.alloys.J.Non-Cryst.Solids1980,38−39,879−884.gHowever,noclearrelationshipcanbefoundbetweenthesehigh(3)Lempicki,A.HighNeodynumcontentaluminophosphateglasscoordinationspecies(Figure9)andtheTgmodification(Figureandlaser,USUS4,371,965,1983.2).Surprisingly,thenumberofAlspeciesinhighcoordination(4)Brow,R.K.;Tallant,D.R.Structuraldesignofsealingglasses.J.Non-Cryst.Solids1997,222,396−406.stateappearstobeabetterparametertoexplaintheTg(5)Donald,I.W.;Metcalfe,B.L.Thermalpropertiesandevolution.AsreportedinFigure11c,theactualnumberofAlcrystallizationkineticsofasodiumaluminophosphatebasedglass.J.speciesin5and6coordinationstates(determinedfromtheglassNon-Cryst.Solids2004,348,118−122.compositionandthe[x]Alrelativeproportions)followsasimilar(6)Mohr,D.;deCamargo,A.S.S.;deAraujo,C.C.;Eckert,H.LocaltrendasTg.ItmayindicatethatTgisgovernedherebytheenvironmentofscandiuminaluminophosphatelaserglasses:structuraloverallnetworktopologyandthealuminumconnectivity.ThestudiesbysolidstateNMRspectroscopy.J.Mater.Chem.2007,17,Al(OP)ngroupscouldthusfillacrucialrole,andthestabilization3733−3738.oftheoverallnumberof[6/5]Alspeciesbeyondthex=3.75(7)Aleksandrova,E.V.;Malkovsky,V.I.;Yudintsev,S.V.StudyofthecompositionwillbeattheoriginoftheTgplateau.Moreover,theStabilityofAluminophosphateGlasses−MatricesforImmobilizationofmoderateincreaseofthenumberof[5,6]Alspecies(0−3.6)couldRadioactiveWaste.Dokl.EarthSci.2018,482,1349−1353.(8)Wang,Y.;Cao,J.;Li,X.;Li,J.;Tan,L.;Xu,S.;Peng,M.alsoexplainwhyTgincreasedinalowerextentthanincaseofthe[5/6]MechanismforbroadeningandenhancingNd3+emissioninzincNasystemforwhichthenumberofAlspeciesincreasesupaluminophosphatelaserglassbyadditionofBi2O3.J.Am.Ceram.Soc.to22inthecompositionaldomainpresentingaTgincrease(0−2018,102,1694−1702.16,3612.5mol%).(9)Brow,R.K.;Kirkpatrick,R.J.;Turner,G.L.LocalStructureofxAl2O3·(1−x)NaPO3Glasses:AnNMRandXPSStudy.J.Am.5.CONCLUSIONCeram.Soc.1990,73,2293−2300.Glasseshavebeenprepareduptox=10mol%inthexAl2O3−(10)Brow,R.K.;Kirkpatrick,R.J.;Turner,G.L.NatureofAluminain27PhosphateGlass:II,StructureofSodiumAlurninophosphateGlass.J.(50−x/2)ZnO−(50−x/2)P2O5line.The1DAlNMRAm.Ceram.Soc.1993,76,919−928.experimentsindicatethepresenceofAlatomsunder6-and5-(11)Smith,C.E.;Brow,R.K.;Montagne,L.;Revel,B.ThestructurefoldcoordinatedconfigurationsatverylowAl2O3amounts,andpropertiesofzincaluminophosphateglasses.J.Non-Cryst.Solidsthesespeciesbeingquicklyandalmostentirelyreplacedby[4]Al2014,386,105−114.species.Thephosphatenetworkisstronglyalteredbythe(12)Wegner,S.;vanWüllen,L.;Tricot,G.ThestructureofintroductionofAlatomsthatproduces(i)aquickdecreaseofaluminophosphateglassesrevisited:Applicationofmodernsolidstate9217https://doi.org/10.1021/acs.jpcc.0c10723J.Phys.Chem.C2021,125,9210−9218

8TheJournalofPhysicalChemistryCpubs.acs.org/JPCCArticleNMRstrategiestodeterminestructuralmotifsonintermediatelengthMultinuclearNMRSpectroscopy.J.Phys.Chem.C2017,121,1838−scales.J.Non-Cryst.Solids2008,354,1703−1714.1850.(13)vanWüllen,L.;Tricot,G.;Wegner,S.AnadvancedNMR(33)Tischendorf,B.;Otaigbe,J.U.;Wiench,J.W.;Pruski,M.;Sales,protocolforthestructuralcharacterizationofaluminophosphateB.C.Astudyofshortandintermediaterangeorderinzincphosphateglasses.SolidStateNucl.Magn.Reson.2007,32,44−52.glasses.J.Non-Cryst.Solids2001,282,147−158.(14)Egan,J.M.;Wenslow,R.M.;Mueller,K.T.Mappingaluminum/(34)Czjzek,G.;Fink,J.;Götz,F.;Schmidt,H.;Coey,J.M.D.;phosphorusconnectivitiesinaluminophosphateglasses.J.Non-Cryst.Rebouillat,J.-P.;Liénard,A.AtomiccoordinationandthedistributionSolids2000,261,115−126.ofelectricfieldgradientsinamorphoussolids.Phys.Rev.B:Condens.(15)Tricot,G.Annu.Rep.NMRSpectrosc.2019,96,35.MatterMater.Phys.1981,23,2513−2530.(16)Zhang,L.;Eckert,H.Short-andMedium-RangeOrderin(35)Tricot,G.;Alpysbay,L.;Doumert,B.SolidstateNMR:ASodiumAluminophosphateGlasses:NewInsightsfromHigh-powerfultoolforthecharacterizationofborophosphateglasses.ResolutionDipolarSolid-StateNMRSpectroscopy.J.Phys.Chem.BMolecules2020,25,428.2006,110,8946−8958.(36)Brow,R.K.NatureofAluminainPhosphateGlass:I,Properties(17)Tricot,G.;Doumert,B.;Revel,B.;Bria,M.;Trebosc,J.;Vezin,H.ofSodiumAluminophosphateGlass.J.Am.Ceram.Soc.1993,76,913−Non-homogeneousdistributionofAl3+indopedphosphateglasses918.(37)Hoppe,U.;Walter,G.;Carl,G.;Neuefeind,J.;Hannon,A.C.revealedby27Al/31PsolidstateNMR.SolidStateNucl.Magn.Reson.StructureofzincphosphateglassesprobedbyneutronandX-ray2017,84,137−142.diffractionofhighresolvingpowerandbyreverseMonteCarlo(18)VanWüllen,L.;Sabarinathan,V.Structureandhightemperaturesimulations.J.Non-Cryst.Solids2005,351,1020−1031.behaviourofsodiumluminophosphateglasses.Phys.Chem.Glasses:Eur.J.GlassSci.Technol.,PartB2016,57,173−182.(19)Tsuchida,J.;Schneider,J.;Rinke,M.T.;Eckert,H.StructureofTernaryAluminumMetaphosphateGlasses.J.Phys.Chem.C2011,115,21927−21941.(20)SrinivasaRao,A.;RupaVenkateswaraRao,B.;Prasad,M.V.V.K.S.;ShanmukhaKumar,J.V.;Jayasimhadri,M.;Rao,J.L.;Chakradhar,R.P.S.SpectroscopicandopticalpropertiesofNd3+dopedfluorinecontainingalkaliandalkalineearthzinc-aluminophosphateopticalglasses.Phys.B2009,404,3717−3721.(21)Li,S.;Huang,S.;Wu,F.;Yue,Y.Structureandpropertiesofzincaluminophosphateglassesandthosedopedwithzirconiumdioxide.J.Non-Cryst.Solids2015,419,45−50.(22)Wang,Q.;Hu,B.;Lafon,O.;Trébosc,J.;Deng,F.;Amoureux,J.P.Double-quantumhomonuclearNMRcorrelationspectroscopyofquadrupolarnucleisubjectedtomagic-anglespinningandhighmagneticfield.J.Magn.Reson.2009,200,251−260.(23)Lesage,A.;Sakellariou,D.;Steuernagel,S.;Emsley,L.Carbon−ProtonChemicalShiftCorrelationinSolid-StateNMRbyThrough-BondMultiple-QuantumSpectroscopy.J.Am.Chem.Soc.1998,120,13194−13201.(24)Trebosc,J.;Hu,B.;Amoureux,J.P.;Gan,Z.Through-spaceR3-HETCORexperimentsbetweenspin-1/2andhalf-integerquadrupolarnucleiinsolid-stateNMR.J.Magn.Reson.2007,186,220−227.(25)Tricot,G.;Trébosc,J.;Pourpoint,F.;Gauvin,R.;Delevoye,L.Annu.Rep.NMRSpectrosc.2014,81,145.(26)Shi,F.;Hu,L.;Cui,Y.;Ren,J.RevealingtheStructuresinShort-andMiddle-OrderofLanthanum-DopedAl2O3−NaPO3GlassesbySolidStateNMRSpectroscopy.J.Phys.Chem.C2021,125,2097−2110.(27)Chan,J.C.C.;Eckert,H.DipolarCouplingInformationinMultispinSystems:ApplicationofaCompensatedREDORNMRApproachtoInorganicPhosphates.J.Magn.Reson.2000,147,170−178.(28)Aitken,B.G.;Youngman,R.E.;Deshpande,R.R.;Eckert,H.Structure−PropertyRelationsinMixed-NetworkGlasses:MultinuclearSolidStateNMRInvestigationsoftheSystemxAl2O3:(30−x)P2O5:70SiO2.J.Phys.Chem.C2009,113,3322−3331.(29)Tricot,G.;Raguenet,B.;Silly,G.;Ribes,M.;Pradel,A.;Eckert,H.P-O-B3linkagesinborophosphateglassesevidencedbyhighfield11B/31PcorrelationNMR.Chem.Commun.2015,51,9284−9286.(30)Elbers,S.;Strojek,W.;Koudelka,L.;Eckert,H.Siteconnectivitiesinsilverborophosphateglasses:newresultsfrom11B{31P}and31P{11B}rotationalechodoubleresonanceNMRspectroscopy.SolidStateNucl.Magn.Reson.2005,27,65−76.(31)Zhang,L.;deAraujo,C.C.;Eckert,H.StructuralRoleofFluorideinAluminophosphateSol−GelGlasses:High-ResolutionDouble-ResonanceNMRStudies.J.Phys.Chem.B2007,111,10402−10412.(32)Uesbeck,T.;Eckert,H.;Youngman,R.;Aitken,B.TheStructureofBorophosphosilicatePureNetworkFormerGlassesStudiedby9218https://doi.org/10.1021/acs.jpcc.0c10723J.Phys.Chem.C2021,125,9210−9218