Fabrication Of White Polymer Light-emitting Diodes Using All-solution Method

Organic Light-Emitting Diode has drawn a great attention in display and lighting areas due to its advantages of active luminescence, high responsiveness, all-solid-state, flexible. OLED has a wide prospects because of these properties. How to simplify the manufacturing process and lower costs are great meaningful in the area of OLED. The main work which this study does use the polymer MEH-PPV as the orange emitting layer, the polymer PFN as the blue emitter to get hybrid white light. Using Cs2CO3as the modified layer, dual-doped highly conductivity PEDOT:PSS as the anode to prepare white organic light emitting device. The study has two parts as follows1. Fabrication of multi-layer polymer light-emitting diodes using all-solution method.I prepare multi-layer polymer light-emitting diodes by using MEH-PPV as orange emitting material, Cs2CO3and PEDOT:PSS as modified layers, highly conductivity PEDOT:PSS as the anode. The maximal intensity of the singer layer diodes is26cd/m2.To heighten properties of device by means of adding modified layers and optimizing the conductions of thin films fabrication. The maximal intensity of the multi-layer diodes heighten to450cd/m2. Experiments were proved the feasibility of fabrication of multi-layer polymer light-emitting diodes using all-solution method.2. Fabrication Of white polymer light-emitting diodes using all-solution methodThe polymer MEH-PPV is used as orange emitting layer. The polymer PFN is used as the electron injection material and the blue emitter. Using Cs2CO3as modified layer, we reduce the turn-on voltage and improve the electron injection ability. The highly conductivity PEDOT:PSS film is used to replace metal electrode as the anode. In this structure, we can get the hybrid white light. By optimizing the conductions of thin films fabrication, we can prove the properties of the device. Our results have shown that the EL spectra of the device extend from400nm to800nm, including the whole visible region, the device starts to glow at4V and exhibits a maximum luminance of1500cd/m2with a maximum current efficiency of0.55cd/A.