Research On The Solution Processed Organic Light Emitting Devices And Materials

Organic light-emitting device(OLED) which possesses many advantages has been applied in commercial TVs and can be widly used in next generation of solid-state lightings in the future. How to get high-performance device and reduce the fabrication cost are the obstacles to achieve the technology commercialized. Solution processes used as fabrication technology of OLED can be considered as an important way to save the device fabrication cost. With the efforts made by researchers, great progresses in solution processed OLED have been achieved. The work of this paper is aimed to construct red, green and blue monochromatic phosphorescent OLED and WOLED with highly performance by using spin-coating process.1. Solution-processed red, green and blue devices with soluble host materials have been fabricated and investigated, these devices have high performance. Furthermore, the application of the home-made yellow-green phosphorescent dopant Ir(ppy)2bop in solution-processed device has been investigated. The Ir(ppy)2bop-based device shows a maximum current efficiency of 33.4 cd/A(9.3%). Blue phosphorescent OLED with F3 Irpic has been investigated, which shows a maximum current efficiency of 35.8 cd/A(12.4%). The purpose of using solution coating process is to reduce the fabrication cost, we studied the application of SQTPA as a hole-transporter in phosphorescent OLED for it’s simple structure and synthetic route. The orange, green and blue devices using SQTPA as hole-transporter show good performance.2. Two-element white devices have been fabricated by using a fabricated process of solution process based on experiments results of monochromatic OLEDs. The white device based on FIrpic owns a maximum current efficiency of 28.6 cd/A(12.8%), and another white device based on F3 Irpic has a maximum current efficiency of 40.9 cd/A(16.9%). The white devices exhibit stable spectra and high efficiency together with mild roll-off.3. Three-color white OLEDs have been fabricated. The white device based on Ir(MDQ)2(acac), Ir(ppy)2acac and FIrpic owns a maximum current efficiency of 26.0 cd/A, a maximum power efficiency of 18.2 lm/W and a maximum external quantum efficiency of 11.1%. The white device based on Ir(MDQ)2(acac), Ir(ppy)2bop and FIrpic gives a maximum current efficiency of 30.0 cd/A, a maximum power efficiency of 20.9 lm/W and a maximum external quantum efficiency of 12.2%.The work of this paper has obtained red, green, blue and white OLED with high efficiency and good performance by employing solution coating process. It is believed that solution processed OLED will be used in commercial fields eventually.