新型间隔层对荧磷杂化白光OLED器件性能的影响

Effect of new spacer layer on fluorescent-phosphorescent hybrid white organic light-emitting devices

以杂化白光结构ITO/HAT-CN(10 nm)/TAPC(30 nm)/TCTA(10 nm)/TCTA:PO-01(10 nm,4%)/MADN:DSA-ph(10 nm,5%)/BPhen(40 nm)/Liq(1 nm)/Al(100 nm)为基础,分别用CBP、SO和SO:TCTA作为间隔层,调节厚度及掺杂比例,研究不同间隔层对杂化白光器件性能的影响。实验结果表明,SO作间隔层可以有效提高电子与空穴在黄光层的复合,增大器件电子传输能力而使器件偏向白光,提高器件效率,且由于SO高的三线态能级,可以有效控制激子复合区域的移动,器件色稳定性也得到提高。再将TCTA与SO掺杂作为间隔层,增强空穴传输,调控空穴和电子的传输与平衡,进一步提升器件性能,当SO∶TCTA掺杂比为9∶1时,有最大电流效率31.60 cd/A,最大功率效率30.16 lm/W,电流密度为10 mA/cm^2时,CIE色坐标为(0.39,0.43),从0.1 mA/cm^2-80 mA/cm^2电流密度变化下色坐标变化(Δx,Δy)仅为(0.02,0.01),色坐标漂移小,色稳定性好。

Based on hybrid white light structure ITO/HAT-CN(10 nm)/TAPC(30 nm)/TCTA(10 nm)/TCTA:PO-01(10 nm,4%)/MADN:DSA-ph(10 nm,5%)/BPhen(40 nm)/Liq(1 nm)/Al(100 nm),CBP,SO and SO:TCTA were used as spacer layers,and the thickness and doping ratio were adjusted to study the effect of different spacer layers on the performance of the hybrid white light device.The experimental results show that the use of SO as a spacer layer can effectively enhance the recombination of electrons and holes in the yellow light emitting layer,increasing the electron transport capability of the device and cause the device to white light,and improves device efficiency.And due to the high triplet level of SO,the movement of the excitons recombination region can be effectively controlled,and the color stability is also improved.Then doping TCTA and SO as a spacer layer to enhance hole transport,regulate the transport and balance of holes and electrons,and further improve device performance.When the doping ratio of SO∶TCTA is 9∶1,the device performance can be further improved,and the maximum current efficiency is 31.60 cd/A and the maximum power efficiency is 30.16 lm/W.When the current density is 10 mA/cm^2,the CIE coordinate is(0.39,0.43),From 0.1 mA/cm^2-80 mA/cm^2 current density the CIE coordinates change(Δx,Δy)is only(0.02,0.01),showing small color drift,good color stability.