Unlock instant, AI-driven research and patent intelligence for your innovation.

A high color stability white light organic electroluminescent device

An electroluminescent device, color stability technology, applied in the direction of electric solid-state devices, electrical components, semiconductor devices, etc., can solve the problems of poor color stability, low efficiency, complex structure, etc., to improve color quality, improve stability, The effect of improving device efficiency

Active Publication Date: 2017-06-23
TAIYUAN UNIV OF TECH
View PDF5 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0007] The purpose of the present invention is to solve the problems of complex structure, poor color stability and low efficiency in traditional multi-light emitting layer white light OLEDs, and to provide a white light organic electroluminescent device with simple structure and high color stability, so that the device can achieve high efficiency. At the same time, it has high color stability, high color quality and simple preparation process

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • A high color stability white light organic electroluminescent device
  • A high color stability white light organic electroluminescent device
  • A high color stability white light organic electroluminescent device

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0042] Fabrication of high color stability white organic electroluminescence device W1 with the following device structure: ITO / MoO 3 (3nm) / CBP (30nm) / CBP: 8wt% Ir(piq) 2 acac (10nm) / CBP: 6wt% Ir(4m3CF4Fpq) 2 (acac)(4.5nm) / CBP: 6wt% Ir(ppy) 3 (2.5nm) / CBP: 20wt% Firpic (8nm) / TPBi: 20wt% Firpic (8nm) / TPBi: 6wt% Ir(ppy) 3 (2.5nm) / TPBi: 6wt% Ir(4m3CF4Fpq) 2 (acac)(4.5nm) / TPBi: 8wt% Ir(piq) 2 acac (10nm) / TPBi (30nm) / LiF (1nm) / Al (200nm).

[0043] The structure of W1 is as follows figure 1 , is composed of transparent conductive thin film anode 2, hole injection layer 3, hole transport layer 4, light emitting layer I5, light emitting layer II6, electron transport layer 7, electron injection layer 8 and cathode deposited on the transparent glass substrate 1 in sequence 9, and an external circuit 10 is connected between the anode 2 and the cathode 9. It is characterized by a pair of symmetrical light-emitting layers, the light-emitting layer I and the li...

Embodiment 2

[0058] The white light device W2 was prepared by changing the film thickness ratios of different color light-emitting layers in Example 1.

[0059] The structure of device W2 is: ITO / MoO 3 (3nm) / CBP (30nm) / CBP: 8wt% Ir(piq) 2 acac(13nm) / CBP: 6wt% Ir(4m3CF4Fpq) 2 (acac) (4nm) / CBP: 6wt% Ir(ppy) 3 (2nm) / CBP: 20wt% Firpic (6nm) / TPBi: 20wt% Firpic (6nm) / TPBi: 6wt% Ir(ppy) 3 (2nm) / TPBi: 6wt% Ir(4m3CF4Fpq) 2(acac) (4nm) / TPBi: 8wt% Ir(piq) 2 acac (13nm) / TPBi (30nm) / LiF (1nm) / Al (200nm).

[0060] The difference from device W1 is that in the light-emitting layer of device W2 in this embodiment, different color light-emitting materials are doped in light-emitting layer I and light-emitting layer II. 2 acac (10nm), Ir(4m3CF4Fpq) 2 (acac)(4.5nm), Ir(ppy) 3 (2.5nm) and Firpic (8nm) are changed to 13nm, 4nm, 2nm and 6nm in device W2, and the detailed preparation, packaging and testing process of the device are exactly the same as W1 in Example 1.

[0061] Th...

Embodiment 3

[0063] A three-band symmetrical light-emitting layer white light device W3 was prepared, and its light-emitting layer is different from the four-band symmetrical light-emitting layer device W1 in Example 1. The specific device structure is: ITO / MoO 3 (3nm) / CBP (30nm) / CBP: 8wt% Ir(piq) 2 acac (12nm) / CBP: 6wt% Ir(ppy) 3 (5nm) / CBP: 20wt% Firpic (8nm) / TPBi: 20wt% Firpic (8nm) / TPBi: 6wt% Ir(ppy) 3 (5nm) / TPBi: 8wt% Ir(piq) 2 acac (12nm) / TPBi (30nm) / LiF (1nm) / Al (200nm).

[0064] In this embodiment, the structure of the device is similar to that of the device W1 in Embodiment 1, except that the light emitting layer is different. The emitting layer of device W3 is as Figure 8 shown, from Figure 8 It can be seen that the luminescent layer of W3 also takes the exciton generation interface as the symmetry axis, and the luminescent layers on both sides are symmetrically distributed. What is different from W1 is that the luminescent layer of the device is com...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

No PUM Login to View More

Abstract

The invention discloses a white light organic electroluminescent device with high color stability, which is composed of an anode, a hole injection layer, a hole transport layer, a light emitting layer I, a light emitting layer II, an electron transport layer, an electron injection layer and a cathode arranged in sequence, The host material I and the host material II of the light-emitting layer I and the light-emitting layer II are materials with hole transport properties and electron transport properties respectively, and the composition of the light-emitting materials doped by the light-emitting layer I and the light-emitting layer II is the same. The interface of layer II is the axis of symmetry, which is symmetrically distributed on both sides of the interface from the high triplet energy level to the low triplet energy level, and the carrier recombination region of the device is located at the interface between the light emitting layer I and the light emitting layer II. The invention improves device efficiency by making full use of exciton energy, controls different color luminescent materials to be located in the carrier recombination region and exciton diffusion range at the same time, improves the color quality of the device, effectively suppresses the change of the carrier recombination region with voltage, and combines the symmetrical light emitting layer The structure improves the color stability of the device.

Description

technical field [0001] The invention belongs to the technical field of organic electroluminescence, and relates to a white light organic electroluminescent device, in particular to a white light organic electroluminescent device which improves the efficiency of the device by making full use of the exciton energy and improves the color stability of the device by using a symmetrical light-emitting layer structure. Luminescent devices. Background technique [0002] From the invention of Incandescent Bulb, to the application of Fluorescent Tube, to the rapid development of solid-state lighting LED (Light Emitting Diode) in recent years, lighting sources have continuously enriched people's modern life, but the accompanying is a high loss of electrical energy. Lighting electricity consumption in developed countries accounts for more than 20% of total electricity consumption, and this proportion is also increasing in developing countries. In addition, in today's highly developed ...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
Patent Type & Authority Patents(China)
IPC IPC(8): H01L51/50H01L51/54
CPCH10K50/11H10K2101/10H10K50/15H10K50/16
Inventor 苗艳勤申倩倩贾虎生王华高志翔李源浩杨君礼武聪伶孙静
Owner TAIYUAN UNIV OF TECH