Pure and Stable Top-Emitting White Organic Light-Emitting Diodes Utilizing Heterojunction Blue Emission Layers and Wide-Angle Interference

Abstract

In top-emitting white organic light-emitting diodes (TWOLEDs), it is usually difficult to realize a good chromaticity due to the strong suppression on the blue emission induced by the microcavity effect. In our work, the blue emission layer (EML) is located near the hole transport layer and the reflective anode to strengthen the wide-angle interference on the blue emission and enhance the output of light. Then we utilize the dual blue EMLs based on an electron-rich heterojunction to constrain most of the excitons in the blue EMLs. With the above two strategies, the intensity of the blue emission is significantly enhanced accompanying the chromaticity improvement in white emission. Some key factors including exciton distribution, energy transfer, and carrier trapping are analyzed to design the structure of the EMLs to acquire the pure and stable white emission. The excellent color stability with a Commission International de L'Eclairage (CIE) coordinate drift of only (0.009, 0.001) in the luminance range of 10-10(4) cd/m(2) is obtained in our optimized TWOLED. The TWOLED also shows the high performances with a maximum luminance of 15360 cd/m(2), the CIE coordinates of (0.33, 0.41), and a current efficiency of 13.3 cd/A.

Efficiently Releasing the Trapped Energy Flow in White Organic Light‐Emitting Diodes with Multifunctional Nanofunnel Arrays

“…The performance of white OLEDs incorporating NFAs was investigated (see the Experimental Section for the device fabrication processes). A standard white emissive layer (EML), which consisted of two complementary colors using bis(3,5‐difluoro‐2‐(2‐pyridyl)phenyl‐(2‐carboxypyridyl) iridium(III) (FIrpic)‐doped N , N ′‐dicarbazolyl‐3,5‐benzene (mCP) for blue emission and Iridium (III) bis[2‐metyyldibenzo (f,h) quinoxaline](acetylacetonate) [Ir(MDQ) 2 (acac)]‐doped mCP for red emission, was used in all devices. The performance characteristics of white OLED with dNFAs and the control device with a flat structure are plotted in Figure .…”

Customizable Organic Charge-Transfer Cocrystals for the Dual-Mode Optoelectronics in the NIR (II) Window

“…The applications of lightweight near-infrared (NIR) optoelectronic semiconductor devices such as solid-state laser, field effect transistor, − light-emitting diodes, − and photodetectors − have gradually gained prominence in the scientific community. Currently, the majority of NIR optoelectronic devices heavily rely on epitaxially grown crystal inorganic materials such as silicon, InGaAs, and III–V compounds .…”

Shape-engineering of organic heterostructures via a sequential self-assembly strategy for multi-channel photon transportation

“…Meanwhile, OHSs inherit the feasibility of large-scale preparation of organic semiconductor and the characteristics of low-cost processing. OHSs involving various morphologies of branched structures [7,8], axial structures [9,10], and network interconnection structures [11] have potential optoelectronic applications, such as light-emitting diodes [12,13], organic field-effect transistors (OFETs) [14][15][16], optical anti-counterfeiting [17], and light-harvesting photovoltaic [18][19][20][21]. For example, recently, the results show that the dual laser has a wide application prospect in full color laser display utilizing OHSs array [22,23].…”