基于荧光材料的有机电致白光发光器件

Organic electroluminescent devices based on fluorescent materials

基于荧光材料的有机电致白光发光器件。以DPVBi荧光材料为蓝色荧光发光层,以DPVBi:DCJTB作为第二层发光层,制备了双层荧光材料的白色有机电致发光器件。器件结构为ITO/MoO3/TCTA/DPVBi/DPVBi:DCJTB/TPBi/LiF/CdS/Al。实验过程首先研究了不同掺杂浓度的单层DPVBi:DCJTB有机电致发光器件,发现制备出的器件均显橙黄色,且1%浓度较好,为了获得白光,在此器件结构基础上又加入了一层蓝色荧光材料DPVBi蓝色荧光发光层,并改变DPVBi的位置,同时通过能及匹配的方法调节DPVBi层与DPVBi:DCJTB层厚度,获得的器件均以蓝光为主,为了进一步获得白光,把掺杂浓度变为3%,并重复了第二次实验,发现DPVBi蓝色发光层在掺杂层前面,并且DPVBi层与DPVBi:DCJTB层厚度为15nm和10nm时获得了白光。本内容的创新点为使用TCTA作为空穴传输层,使能级更加匹配,增加了空穴的注入,同时使用CdS作为电子注入层,增加了电子的注入,很好地解决了空穴和电子注入不平衡而带来的效率低的问题,并且通过使用改变掺杂浓度的方法和交换发光层位置的方法获得了CIE坐标为(0.38,0.32)的白光器件。

Organic electroluminescent devices based on fluorescent materials.A white organic electroluminescent device with double-layer fluorescent material was prepared with DPVBi fluorescent material as the blue fluorescent layer and DPVBi:dcjtb as the second light-emitting layer.The device structure is ITO/MoO3/TCTA/DPVBi/DPVBi:dcjtb/tpbi/LIF/CdS/Al.Firstly,the single-layer DPVBi:dcjtb organic electroluminescent devices with different doping concentrations were studied.It was found that the prepared devices showed orange yellow and 1%concentration was good.In order to obtain white light,a blue fluorescent material DPVBi blue fluorescent layer was added on the basis of the device structure,and the position of DPVBi was changed,At the same time,the thickness of DPVBi layer and DPVBi:dcjtb layer is adjusted by the method of energy and matching.The obtained devices are mainly blue light.In order to further obtain white light,the doping concentration is changed to 3%,and the second experiment is repeated.It is found that DPVBi blue light-emitting layer is in front of the doped layer,and white light is obtained when the thickness of DPVBi layer and DPVBi:dcjtb layer is 15nm and 10nm.The innovation of this content is that TCTA is used as the hole transport layer to make the energy levels more matched and increase the hole injection.At the same time,CDs is used as the electron injection layer to increase the electron injection,which solves the problem of low efficiency caused by the imbalance between hole and electron injection,A white light device with CIE coordinates of(0.38,0.32)was obtained by changing the doping concentration and exchanging the position of the light-emitting layer.