Skip to Main content Skip to Navigation
Theses

Diodes électroluminescentes hybrides organiques inorganiques : Mécanismes aux interfaces, courant et lumière.

Abstract : The hybrid organic-inorganic Quantum Dot Light-Emitting Diodes-(QD-LEDs) are devices intended to associate the semiconducting properties of conjugated organic materials and ease of implementation in a thin layer, to the unique properties (color tunable by the size, good luminescence quantum yield) of nanoparticles inorganic semiconductors such as CdSe/ZnS (TOPO). Various approaches have been explored to optimize the QD-LEDs and are based on the achievement of various architectures (uni, bi, tri-layer) combining organic materials with QDs (in compact layer or dispersed in a matrix), deposited by various methods (spin coating, stamp, ink jet printing). In this thesis, we first devised an original structure in the form of diodes comprising a layer hybrid nanocomposite, obtained by incorporating QDs in a dielectric matrix of PMMA. The aim was to control the flow of carriers to maximize their recombination on QDs. Measurements of electrical, electro and photoluminescence are discussed, together with studies of the morphology of deposits by AFM, which have shown how the microstructure depended on the characteristics of solvents used for spin coating. In general, the nanoparticles are aggregated and inhomogeneous layer appears rough, allowing contact between the transport layers. The resulting low electroluminescence proceeds by transfer from excited states produced by recombination at these locations. In a second part, we introduced QDs by spin coating from solutions in heptane, a solvent that does not disturb previously deposited organic layers. The morphologies observed are those of compact islands, with coverage rates ranging from 0 to 100 %. The reduction, and eventual disappearance, of electroluminescence at high coverages confirm that the emission of QDs originates exclusively from transfer of excitation from the excited species generated at the interface of organic-organic, depending on the type of organics. The mechanisms of carrier injection at the cathode, depending on its nature of and the electron transport layer, are variable as well.
Document type :
Theses
Complete list of metadatas

Cited literature [197 references]  Display  Hide  Download

https://tel.archives-ouvertes.fr/tel-00526529
Contributor : Abdelmalek Ainsebaa <>
Submitted on : Thursday, October 14, 2010 - 9:54:56 PM
Last modification on : Wednesday, December 9, 2020 - 3:10:15 PM
Long-term archiving on: : Saturday, January 15, 2011 - 2:30:15 AM

Identifiers

  • HAL Id : tel-00526529, version 1

Citation

Abdelmalek Ainsebaa. Diodes électroluminescentes hybrides organiques inorganiques : Mécanismes aux interfaces, courant et lumière.. Matériaux. Université Paris-Diderot - Paris VII, 2010. Français. ⟨tel-00526529⟩

Share

Metrics

Record views

801

Files downloads

4385