NiO as an inorganic hole-transporting layer in quantum-dot light-emitting devices
Jean-Michel Caruge1, Jonathan E Halpert, Vladimir Bulović
1Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, USA.
Nano Letters
|December 14, 2006
Abstract:
We demonstrate a hybrid inorganic/organic light-emitting device composed of a CdSe/ZnS core/shell semiconductor quantum-dot emissive layer sandwiched between p-type NiO and tris-(8-hydroxyquinoline) aluminum (Alq3), as hole and electron transporting layers, respectively. A maximum external electroluminescence quantum efficiency of 0.18% is achieved by tuning the resistivity of the NiO layer to balance the electron and hole densities at quantum-dot sites.
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