(兰州理工大学 1. 材料科学与工程学院;2. 理学院, 兰州 730050)
(1. School of Materials Science & Engineering;2. School of Science, Lanzhou University of Technology, Lanzhou 730050, CHN)
Electron-only devices with different structures were prepared by doping Liq (8-hydroxyquinolinato-lithium) into the electron transport layer Alq (tris(8-hydroxyquinolinato) aluminum). The experimental results show that the electrical properties of doped devices are inferior to those of non-doped devices with Liq/Al composite cathodes and superior to those of non-doped devices with Al only cathodes. This indicates that Liq’s doped with Alq does not show any significant “n-doping” effect. The effect exhibits dual roles:Liq molecules dispersed at the Alq/Al cathode interfaces after doping display as electron injection layers, which enhances the device currents by enhancing electron injection; those in the bulk of Alq after doping have a detrimental effect on electron transport due to their own poor conductivity, consequently decrease the device currents. In the tests of electroluminescent devices, the doping of Liq shows a similar behavior. The performance of Liq-doped device is between the non-doped devices with Liq/Al cathode and Al cathode structures, with maximum current efficiencies of 3.96,4.27 and 2.27cd/A for the three devices, respectively, and no additional changes caused by charge transfer are observed in the absorption and photoluminescent spectra.
苏江森,吴有智,邹文静,张材荣. Alq基有机发光二极管中Liq的“n型掺杂”机理研究[J].半导体光电,2023,44(4):556-561. SU Jiangsen, WU Youzhi, ZOU Wenjing, ZHANG Cairong. Mechanism of Liq's “N-Type Doping” in Alq Based Organic Light-Emitting Diodes[J].,2023,44(4):556-561.复制