Organic Light Emitting Device of CdSe Nanocrystals: Fabrication and Characterization

Abstract

Quantum dots organic light-emitting device (QDOLED) was assembled with                  ITO/TPD: PPV/CdSe/Alq₃/Ni synthesized system via the technique of phase separation. The white light-emitting electroluminescence (EL) system consists of three layers deposited successively on the ITO glass substrate surface; the first layer consisted of Tetra-Phenyl Diaminobiphenyl (TPD) polymer combined with Poly (PPV) organic polymers in the ratio 1:1, while the second layer consisted of CdSe QDs. At last, deposition is the Alq₃ upper layer the CdSe QDs layer.  The created white light properties with reasonable efficiency using confinement effect that changes the energy gap larger, so the direction of the light sites is close to the center of white light color. Current-voltage (I-V) attributes show a strong output current relative to the few voltages (5.5 V) that are used to produce acceptable white light output performance. Classified based on the coordinate system of chromaticity (CIE 1931) it was identified that the emission levels able to produce this white luminescence have been (x=0.31, y=0.33) and correlated color temperature (CCT) was realized about 6250 K. The production of CdSe QDs EL-devices with organic polymer hole injection (PPD TPD) and organic molecules (Alq₃) was successful in white light production.

Keywords- Quantum Dots; White Light; CdSe; TPD; PPV; Alq₃