LuminolchemiluminescenceinducedbysilvernanoparticlesinJournalofPhotochemistryandPhotobiologyA:Chemistry215(2021)185–190ContentslistsavailableatScienceDirectJournalofPhotochemistryandPhotobiologyA:Chemistryjournalhomepage:/locate/jphotochemLuminolchemiluminescenceinducedbysilvernanoparticlesinthepresenceofnucleophilesandCu2+NaLi,JieGu,HuaCuiCASKeyLaboratoryofSoftMatterChemistry,DepartmentofChemistry,UniversityofScienceandTechnologyofChina(USTC),230026Hefei,Anhui,PRChinaarticleinfoabstractItwasfoundthatsilvernanoparticles(NPs)inthepresenceofnucleophilesandCu2+couldinduceluminoltoproducechemiluminescence(CL).TheAgNPs–NaBr–CuSO4–luminolsystemwaschosenasamodelsystemtostudytheCLmechanism.UV–visabsorptionspectrashowedthatsilvernanoparticlesinthepresenceofNaBrcouldreactwithCuSO4beforeinjectionofluminol.TheX-raydiffractionpat-ternsandX-rayphotoelectronspectrademonstratedthatCu(I)complexwasakeyreactionproductinAgNPs–NaBr–CuSO4system.Besides,itwasalsofoundthatsuperoxidedismutasecouldinhibittheCL,revealingthatasuperoxideanionwasinvolvedintheCLreaction.Onthisbasis,itwassuggestedthattheluminolCLinducedbysilvernanoparticlesinthepresenceofNaBrandCu2+derivedfromCu(I)complexformedviathereductionofCuSO4byAgNPsbytheaidofNaBr,whichreactedwiththedissolvedoxygentogeneratethesuperoxideanion;thenthesuperoxideanionreactedwithluminoltoproduceCL.BrasanucleophilewasconsideredtodecreasetheoxidationpotentialofsilvernanoparticlessothatCu(II)isreadilyreducedtoCu(I)andtobindtoCu(I)preventingCu(I)fromdismutationinwater.Asexpected,othernucleophilessuchasCl,Iandthiosulfate,whichwerealsoefcienttodecreasetheoxidationpotentialofAgNPsandbindtoCu(I),couldalsoinducetheluminolCL.2021ElsevierB.V.Allrightsreserved.Articlehistory:Received4May2021Receivedinrevisedform30July2021Accepted17August2021Availableonline24August2021Keywords:AgnanoparticleNucleophileChemiluminescenceLuminol1.IntroductionInrecentyears,nanoparticles(NPs)havebeenwidelystudiedfortheirexcellentproperties[1–3]andtheirpotentialapplicationsinmicroelectronics,optics,electronics,magneticdevices,andcataly-sis[4–8].Intheseinvestigations,anumberofreportsfocusonthepropertiesofNPsinthepresenceofnucleophiles[9–11].Absorp-tionofthesenucleophilesonsilverNPscandrasticallychangetheiropticalpropertiesandredoxreactivity[12,13].Thesilveratomsonthesurfacearecoordinativelyunsaturated.Onemayexpectthatunoccupiedorbitalsexistonthesurfaceintowhichanucleophilicreagentcandonateanelectronpair.Theconsequenceisnotonlyachangeintheopticalabsorptionofthecolloidalparticlesbutalsoachangeintheirreactivity.Theinteractionofsurfaceatomswithnucleophilesleadstoapartialoxidationofsurfaceatoms,whiletheinteriorofcolloidalparticlesreceivesacorrespondingnegativechargewhichcanbepickedupbytheelectronacceptors.Cu2+hasbeenusedasatypicalelectronacceptortotesttheenhancedredoxcapabilityofthesilverNPsinthenucleophiles.Withoutthenucle-ophiles,additionofCu2+couldnotresultintheoxidationofsilverparticles.TheFermileverofsilverNPsmodiedbynucleophileswassignicantlyshiftedtowardanegativepotential,andismoreCorrespondingauthor.Tel.:+865513606645;fax:+865513600730.E-mailaddress:hcui@(H.Cui).1010-6030/$–seefrontmatter2021ElsevierB.V.Allrightsreserved.doi:10.1016/j.jphotochem.2021.08.016negativethanthestandardredoxpotentialoftheCu2+/Cu+cou-ple.Asaresult,thereducingabilityofsilverNPsinthepresenceofnucle...