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Semiconductor nanocrystals dispersed in imidazolium-based ionic liquids: a spectroscopic and morphological investigation

  • Annamaria Panniello
  • Enrico Binetti
  • Chiara Ingrosso
  • M. Lucia Curri
  • Angela Agostiano
  • Raffaele Tommasi
  • Marinella StriccoliEmail author
Research Paper

Abstract

A growing interest is devoted to the study of imidazolium-based ionic liquids as innovative materials to combine with functional elements for advanced technological applications. Materials based on semiconductor and oxide nanocrystals in ionic liquids can be promising for their integration in lithium batteries, as well as in innovative solar cells. Although the physical chemical properties and the solvation dynamics of bare ionic liquids have been extensively studied, their combination with colloidal nanocrystals still remains almost unexplored. Here, the optical properties of organic-capped luminescent cadmium selenide nanocrystals coated by a shell of zinc sulfide (CdSe(ZnS)) dispersed in 1,3-dialkyl imidazolium ionic liquids have been investigated, also in dependence of the alkyl chain length on the imidazolium ring and of the anion nature, by using both time-integrated and time-resolved optical spectroscopy. The observed variations in decay profiles of the ionic liquid in presence of colloidal nanocrystals suggest that the dispersion of the nanostructures induces modifications in the ionic liquid structural order. Finally, atomic force microscopy analysis has provided insight into the topography of the investigated dispersions deposited as film, confirming the organization of the ionic liquids in super-structures, also upon nanocrystal incorporation.

Keywords

Colloidal nanocrystals Ionic liquids Luminescence Optical spectroscopy Time-resolved emission spectroscopy 

Notes

Acknowledgments

This study has been financially supported by the EU 7th FP ORION project (CP-IP 229036-2). The authors gratefully thank Solvionic (France) for supplying the ILs.

Supplementary material

11051_2013_1567_MOESM1_ESM.docx (466 kb)
Supplementary material 1 (DOCX 466 kb)

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Copyright information

© Springer Science+Business Media Dordrecht 2013

Authors and Affiliations

  • Annamaria Panniello
    • 1
  • Enrico Binetti
    • 1
  • Chiara Ingrosso
    • 1
  • M. Lucia Curri
    • 1
  • Angela Agostiano
    • 1
    • 2
  • Raffaele Tommasi
    • 1
    • 3
  • Marinella Striccoli
    • 1
    Email author
  1. 1.IPCF Bari DivisionC.N.RBariItaly
  2. 2.Chemistry DepartmentUniversity of Bari “Aldo Moro”BariItaly
  3. 3.Department of Basic Medical SciencesNeuroscience and Sense Organs, University of Bari “Aldo Moro”BariItaly

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