Polymer Light Emitting Diodes and Bistable Devices Based on Polyfluorene Containing Au Nanoparticles

Autor: kuo cheng chen, 陳國政
Rok vydání: 2005
Druh dokumentu: 學位論文 ; thesis
Popis: 93
Recently, polymer light emitting diodes (PLEDs) are the most potential technology for panel display. Because of possessing many advantages, such as easy processing, low threshold voltage, self-emission properties, short response time, large view angle, and mechanical flexibility, PLEDs are promising technology for next-generation flat panel display. However, short life time and low luminescence of devices limited the development of PLEDs. The gold nanoparticles (AuNPs) were applied to enhance the current density and luminescence. One of the factors determining the performance of devices is the flux balance of charge carriers. Therefore, Poly9,9-dioctylfluorene-alt- thiophene (PFOT) were synthesized and bonded with different concentrations of AuNPs (PFOT-Au). We use three kinds of materials as emitting layer which PFOT, PFOT-Au and mixing Au nanoparticles (PFOT/Au). The suitable concentration of gold nanoparticles can improve the electrons injection and charge carriers combination. The devices of PFOT-Au exhibited an enhanced electron injection due to the extended interface between the cathode and emitting layer. Compare to the other devices, the devices fabricated by PFOT-Au not only improved the luminescence and current efficiency but also reduced the threshold voltage. The threshold voltage, luminescence and current efficiency of PFOT-Au devices are 6V, 7910 cd/m2 and 0.708 cd/A, respectively. Utilization of the electric-field induced charge transfers mechanism between the AuNPs and polymers, PFOT-Au and PFOT/Au were applied to fabrication of memory devices. Because of good stability in the high conductively state, PFOT-Au and PFOT/Au devices can also be used as a write-once-read-many time electronic memory.
Databáze: Networked Digital Library of Theses & Dissertations
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