Polymer LED Utilizing Poly(arylene vinylenes)
Polymer light emitting diode, P-LED, has successfully been fabricated using highly luminous poly(arylene vinylene) derivatives. The P-LED showed a maximum luminance of 55,000cd/m2. This high performance of the device was achieved by employing copolymers of arylene vinylene units as a light-emitting material and a multi-layer structure for the device.
Structural and energetical irregularity introduced into the conjugated polymers gave us a highly luminous polymer due to confinement of excitons. The irregularity can be formed by copolymerization of conjugated/non-conjugated segments, m/p-phenylene vinylenes and alkyl/alkoxy-substituted phenylene vinylenes. Among the copolymers, the m/p-phenylene vinylene copolymer gave a highly efficient P-LED device due to the balance of the exciton confinement and the charge transporting property.
KeywordsRandom Copolymer Apply Physic Letter Device Efficiency Maximum Luminance Phenylene Vinylenes
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