Air-stable organic polymer red light-emitting devices on flexible plastic substrates

The DPVBi (4,4′-bis(2,2-diphenylvinyl-1,1′-biphenyl) is a blue-light organic fluorescence doped material, which can be used as a hole barrier layer or a luminescent layer for fabricating organic light-emitting devices. A blue light device with stable color stability and high efficiency was prepared by co-doping blue light dye DPVBi and red light dye DCJTB as light-emitting layer. In order to prevent the infiltration of O2 and moisture inside the device from affecting the luminescence lifetime of the device, the device was encapsulated by atomic layer deposition. Since the driving voltage of the organic light-emitting device is generally above 5 V and the power consumption is low, in order to facilitate driving with a low voltage, a boost driving circuit based on the XL6009 chip was designed. The driver of the fabricated blue-light device was tested. The results showed that circuit had low-voltage drive characteristics and could be widely used in small toys, lighting, and portable devices. Through the test to achieve the desired goal, the requirements of low voltage and low energy consumption were realized, and the life of the light-emitting device can be tested, which has certain practicability and reference value.

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Fabrication of Quantum Dots Light Emitting Device by Using CdTe Quantum Dots and Organic Polymer

Journal of Nano Research ◽

10.4028/www.scientific.net/jnanor.50.48 ◽

2017 ◽

Vol 50 ◽

pp. 48-56 ◽

Cited By ~ 4

Author(s):

Akeel M. Kadim

Keyword(s):

White Light ◽

Phase Segregation ◽

Organic Polymer ◽

Light Emitting ◽

Light Emitting Devices ◽

Hybrid Device ◽

Cdte Qds ◽

Junction Device ◽

Ito Glass ◽

Hybrid Junction

Cadmium telluride CdTe QDs was prepared by chemical reaction and used to fabricate electroluminescence quantum dot hybrid junction device. QD-LED was fabricated using TPD: PMMA/CdTe/Alq3 device which synthesized by phase segregation method. The hybrid white light emitting devices consists, of three-layers deposited successively on the ITO glass substrate; the first layer was of Tetra-Phenyl Diaminobiphenyl (TPD) polymer mixed with polymethyl methacrylate (PMMA) polymers, while the second layer was 0.5wt% of the (CdTe) QDs for hybrid device, whereas the third layer was Tris (8-hydroxyquinoline) aluminium (Alq3). The optical properties of CdTe QDs were considered by UV-Vis. and photoluminescence (PL) spectrometer. The results show that the prepared QDs were nanocrystalline with defects formation. The Eg calculated from PL were 2.25 eV for Cadmium telluride CdTe QDs was prepared by chemical reaction and used to fabricate electroluminescence quantum dot hybrid junction device. QD-LED was fabricated using TPD: PMMA/CdTe/Alq3device which synthesized by phase segregation method. The hybrid white light emitting devices consists, of three-layers deposited successively on the ITO glass substrate; the first layer was of Tetra-Phenyl Diaminobiphenyl (TPD) polymer mixed with polymethyl methacrylate (PMMA) polymers, while the second layer was 0.5wt% of the (CdTe) QDs for hybrid device, whereas the third layer was Tris (8-hydroxyquinoline) aluminium (Alq3). The optical properties of CdTe QDs were measuredby UV-Vis. and photoluminescence (PL) spectrometer. The results show that the prepared QDs were nanocrystalline with defects formation. The Eg calculated from PL were 2.25 eV for CdTe QDs. The generated white light properties with acceptable efficiency using confinement effect that makes the energy gap larger, thus the direction of the light sites are toward the center of white light color. The organic light emitting device (OLED) wasconsidered by room temperature PL and electroluminescence (EL). Current-voltage (I–V) characteristics indicate that the output current is good compared to the few voltage (6 V) used which gives good results to get a generation of white light. The electroluminescence (EL) spectrum of hybrid deviceshows a wide emission band covering the range from 350 - 700 nm. The emissions causing this white luminescence were identified depending on the chromaticity coordinates (CIE 1931) was found (x=0.32, y=0.33). The correlated color temperature (CCT) was found to be about 5886 K. Fabrication of EL-devices from semiconductors material (CdTe QDs) between two layers organic polymer (TPD) and organic molecules (Alq3) were effective in white light generation. The recombination processes and I-V characteristics gives rises to the output current is good compared to the few voltages used which gives good results to become a generation of light.

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