Electroluminescence from a mixed red-green-blue colloidal quantum dot monolayer.
We demonstrate light emitting devices (LEDs) with a broad spectral emission generated by electroluminescence from a mixed-monolayer of red, green, and blue emitting colloidal quantum dots (QDs) in a hybrid organic/inorganic structure. The colloidal QDs are reproducibly synthesized and yield high luminescence efficiency materials suitable for LED applications. Independent processing of the organic charge transport layers and the QD luminescent layer allows for precise tuning of the emission spectrum without changing the device structure, simply by changing the ratio of different color QDs in the active layer. Spectral tuning is demonstrated through fabrication of white QD-LEDs that exhibit external quantum efficiencies of 0.36% (Commission Internationale de l'Eclairage) coordinates of (0.35, 0.41) at video brightness, and color rendering index of 86 as compared to a 5500 K blackbody reference.
Anikeeva
Polina O
PO
Laboratory of Organic Optics and Electronics, Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.
Halpert
Jonathan E
JE
Bawendi
Moungi G
MG
Bulović
Vladimir
V
D003102:Colloids / Q000737:chemistry; D003116:Color; D003460:Crystallization / Q000379:methods*; D004563:Electrochemistry / Q000295:instrumentation* / Q000379:methods; D008027:Light; D008029:Lighting / Q000295:instrumentation / Q000379:methods*; D008163:Luminescent Measurements / Q000295:instrumentation* / Q000379:methods; D046911:Macromolecular Substances / Q000737:chemistry; D008422:Materials Testing; D008968:Molecular Conformation; D049329:Nanostructures / Q000737:chemistry* / Q000528:radiation effects / Q000648:ultrastructure; D036103:Nanotechnology / Q000295:instrumentation* / Q000379:methods; D010316:Particle Size; D045663:Quantum Dots; D013499:Surface Properties
D003102:Colloids; D046911:Macromolecular Substances