在空穴传输层中掺杂F4-TCNQ提高绿色有机电致发光器件性能

Utilizing doped F4-TCNQ in the hole transporting layers to enhance performance of green organic light emitting diode

研究了在空穴传输层2T-NATA中掺杂不同浓度的p型氧化剂F4-TCNQ制备高性能的绿色有机电致发光器件(OLED).F4-TCNQ在空穴传输层2T-NATA中的掺杂浓度为8%(质量百分比)时(驱动电压为22V),其亮度达到4256cd/m^2,同时与未掺杂的器件相比,其最大发光效率由2.9cd/A增大到3.4 cd/A.分析结果表明,OLED性能的改善主要归因于:首先,掺杂F4-TCNQ使得器件做到了欧姆接触,使消耗在ITO/空穴传输层界面的电压达到最小;其次,掺杂F4-TCNQ提高了载流子形成激子的几率,最终使器件性能得到了很大程度的改善.

A high performance green organic light emitting diode （OLED） was studied by using the doped p-type oxidant F4-TCNQ in the hole transporting layers （HTL） of 2T-NATA. When the doping concentration of F4-TCNQ （mass percentage） was 8% in the HTL （at the drive voltage of 22 V）, the brightness of the OLED was as high as 4256cd/m^2; at the same voltage, compared with the undoped, the maximum ele.c7 troluminescence efficiency was increased from 2.9 cd/A to 3.4 cd/A. The reasons of these improvements are as follows： on the one hand, F4-TCNQ doped device makes ohmic contact, which increases effective driving voltage of the device; on the other hand, by doping p-type oxidant F4-TCNQ in the HTL, the carrier tunneling mechanisms can make effective transference, and this might form more exciton, and finally improves properties of the OLED.