一种新型共轭聚合物发光二极管老化的拉曼光谱研究

Study on the Degradation of Polymer Light-Emitting Diodes by In-Situ Micro-Raman Spectroscopy

通过显微共焦拉曼光谱 ,对一种以新型的共轭聚合物半导体材料 3,4 (2 乙基己氧基 )苯基 1,3 丙二醇酯 (poly(2 (4 Ethylhexyl) phenyl 1,4 phenylenevinylene) (P PPV) )为发光层的聚合物发光二极管(PLEDs)器件进行了老化研究 ,无论是光致发光光谱还是拉曼光谱都提供证据说明造成器件老化的原因主要是发光层的聚合物的主链结构 ,即聚合物的共轭结构被破坏 ,这对提高以P PPV作为发光层的PLEDs器件的性能提出有用信息。

The authors report Raman degradation study of polymer light-emitting devices under ambient conditions. In order to investigate the chemical degradation reaction in polymer light-emitting diode (PLEDs) devices, the chemical structure of the poly (2(4-Ethylhexyl) phenyl-1, 4-phenylene vinylene) (P-PPV) polymer was analyzed by micro-Ramam spectroscopy during the lifetime of the devices. The evidence for the reduction of conjugation length is provided by Raman spectroscopy. This reduction of the conjugation length, which dramatically increases the resistance and cuts off the current density, was the main reason for the failure of lighting. These findings provide an important insight into the intrinsic degradation mechanisms of the polymer LEDs and help in the development of even more stable devices.