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Thermally activated delayed photoluminescence from pyrenyl-functionalized CdSe quantum dots

Nature Chemistry volume 10, pages 225230 (2018) | Download Citation


The generation and transfer of triplet excitons across semiconductor nanomaterial–molecular interfaces will play an important role in emerging photonic and optoelectronic technologies, and understanding the rules that govern such phenomena is essential. The ability to cooperatively merge the photophysical properties of semiconductor quantum dots with those of well-understood and inexpensive molecular chromophores is therefore paramount. Here we show that 1-pyrenecarboxylic acid-functionalized CdSe quantum dots undergo thermally activated delayed photoluminescence. This phenomenon results from a near quantitative triplet–triplet energy transfer from the nanocrystals to 1-pyrenecarboxylic acid, producing a molecular triplet-state ‘reservoir’ that thermally repopulates the photoluminescent state of CdSe through endothermic reverse triplet–triplet energy transfer. The photoluminescence properties are systematically and predictably tuned through variation of the quantum dot–molecule energy gap, temperature and the triplet-excited-state lifetime of the molecular adsorbate. The concepts developed are likely to be applicable to semiconductor nanocrystals interfaced with molecular chromophores, enabling potential applications of their combined excited states.

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This work was supported by the Air Force Office of Scientific Research (FA9550-13-1-0106) and the US Department of Energy, Office of Science, Office of Basic Energy Sciences, under award no. DE-SC0011979. P.M. and M.Z. were supported by award no. DE-SC0016872, funded by the US Department of Energy, Office of Science.

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    • Cédric Mongin

    Present address: Laboratoire PPSM, ENS Paris-Saclay, 61 avenue du Président Wilson, 94235 Cachan CEDEX, France


  1. Department of Chemistry, North Carolina State University, Raleigh, North Carolina 27695-8204, USA

    • Cédric Mongin
    •  & Felix N. Castellano
  2. Department of Physics and Center for Photochemical Sciences, Bowling Green State University, Bowling Green, Ohio 43043, USA

    • Pavel Moroz
    •  & Mikhail Zamkov


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C.M. contributed to the preparation and characterization of the PCA-containing CdSe materials, all of the photophysical experiments, data analysis and manuscript composition. P.M. contributed to the preparation and characterization of the native CdSe-OA materials. M.Z. contributed to the preparation and characterization of the native CdSe-OA materials and manuscript composition. F.N.C. contributed to the original research concept, data analysis, manuscript composition and overall supervision of the project.

Competing interests

The authors declare no competing financial interests.

Corresponding author

Correspondence to Felix N. Castellano.

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