PCDTBT作为发光层的有机电致发光器件研究

Organic light-emitting devices based on PCDTBT as emitting layer

使用PCDTBT作为发光层材料,制备了发光波长为705 nm的红色有机电致发光器件,其结构为ITO/PEDOT:PSS/PCDTBT/BCP/LiF/Al.器件启亮电压为2 V,在9 V时器件达到最高亮度,为29000 cd/m2,最大电流效率为3.5 cd/A.还研究了不同退火温度对器件发光性能的影响.实验结果表明,退火温度为50?C时器件的性能最佳,其原因是此时既有利于溶剂挥发,又保持了分子结构的稳定性,而高温退火降低了PCDTBT的π-π堆积的有序性,从而使得器件性能下降.

Here we report a red organic electroluminescent device （OLED） with an emission wavelength at 705 nm in which PCDTBT is used as an emitting layer with the structure ITO / PEDOT：PSS / PCDTBT / BCP / LiF /Al. The device shows good performances such as an onset voltage of 2 V, a maximum brightness of 29000 cd/m2 at 9 V and a maximum current efficiency of 3.5 cd/A. The effects of annealing on the luminescent property of the device are studied at different temperatures. The experimental results suggest that the device presents the best performance at an annealing temperature of 50 ℃, then the performance decreases with annealing temperature increasing. We find that relatively low temperature annealing is beneficial to the solvent evaporation, and the high temperature annealing is conducible to reducing the coherence length of theπ-πstacking, which results in the degradation of the performance of the device.