Influence of 3D aggregation on the photoluminescence dynamics of CdSe quantum dot films

• DOI: 10.1016/j.jlumin.2016.11.002
• Publication Date: 2016-11-09T23:31:55Z
• Authors: T. Alejo; Pedro M.R. Paulo; M.D. Merchán; Emilio Garcia-Fer...; Sílvia M.B. Costa; M.M. Velázquez
• Keywords: Confocal fluorescence lifetime microscopy; Quantum dots; Langmuir-blodgett films; Photoluminescence properties; 02 engineering and technology; 0210 nano-technology

[EN]Thin films ofsemiconductorCdSequantumdots,QDs,directlydepositedontoquartzaswellasontoa Langmuir-Blodgett film oftheGeminisurfactantethyl-bis(dimethyloctadecylammoniumbromidehave been preparedandtheirphotoluminescencepropertieswerecharacterizedbyconfocal fluorescence lifetime microscopy.3DaggregatesofQDswereobservedinQD films directlydepositedontothesolid while theGeminisurfactant film avoidsthe3Daggregation.Thephotoluminescencedecayanalysiswas performed byaphenomenologicalmodelpreviouslyproposedbyuswhichconsidersthatthelumi- nescence dynamicsisaffectedbyenergytransportandtrappingprocessesandtherelativecontribution of theseprocessesdependson film morphology.Thus,inthenon-aggregatedandmorehomogeneousQD films, QDsdepositedontothesurfactant,therelativecontributionoftheenergytransportprocessin- creases withtrapconcentrationwhile3Daggregationfavorstheenergytransportevenatlowdensityof energy traps.