Highly luminescent colloidal CdS quantum dots with efficient near-infrared electroluminescence in light-emitting diodes
Abstract
Quantum dots are of growing interest as emissive materials in light emitting devices. Here first we report the formation of highly luminescent organic capped colloidal cadmium sulfide (CdS) nanoparticles having the highest photoluminescence quantum yield of 69% in solutions and 34% in neat thin films in the near-infrared range. Second, we also show efficient electroluminescence in the near-infrared from solution processed hybrid light emitting diodes (LEDs) based on such colloidal CdS quantum dots embedded in an organic semiconductor matrix forming a nanocomposite active layer. We also discuss the device structure and role of the doped active layer in efficiency improvement. With optimized active layer thickness and concentration of QDs, the device exhibits an external electroluminescence quantum efficiency of 0.62% at a peak emission wavelength of 760 nm, providing a route to solution processable flexible light sources for biosensors and medicine.
Citation
Bansal , A K , Antolini , F , Zhang , S , Stroea , L , Orlotani , L , Lanzi , M , Serra , E , Allard , S , Scherf , U & Samuel , I D W 2016 , ' Highly luminescent colloidal CdS quantum dots with efficient near-infrared electroluminescence in light-emitting diodes ' , Journal of Physical Chemistry C , vol. 120 , no. 3 , pp. 1871-1880 . https://doi.org/10.1021/acs.jpcc.5b09109
Publication
Journal of Physical Chemistry C
Status
Peer reviewed
ISSN
1932-7447Type
Journal article
Rights
This is an open access article published under a Creative Commons Attribution (CC-BY) License, which permits unrestricted use, distribution and reproduction in any medium, provided the author and source are cited.
Description
We acknowledge financial support from FP7 project “Laser Induced Synthesis of Polymeric Nanocomposite Materials and Development of Micro-Patterned Hybrid Light Emitting Diodes (LED) and Transistors (LET)”-LAMP (Project G.A.247928). A.K.B. and I.D.W.S. also acknowledge financial support from EPSRC Programme “Challenging the Limits of Photonics: Structured Light” Grant EP/J01771X/1.Collections
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