Impact of compound doping on hole and electron balance in p-i-n organic light-emitting diodes
Xin-Xin Wang,
Jing Xiao,
Xu Gao,
Xiao-Hong Zhang,
Sui-Dong Wang
Affiliations
Xin-Xin Wang
Institute of Functional Nano & Soft Materials (FUNSOM) & Collaborative Innovation Center of Suzhou Nano Science and Technology, Soochow University, Suzhou, Jiangsu 215123, P. R. China
Jing Xiao
Institute of Functional Nano & Soft Materials (FUNSOM) & Collaborative Innovation Center of Suzhou Nano Science and Technology, Soochow University, Suzhou, Jiangsu 215123, P. R. China
Xu Gao
Institute of Functional Nano & Soft Materials (FUNSOM) & Collaborative Innovation Center of Suzhou Nano Science and Technology, Soochow University, Suzhou, Jiangsu 215123, P. R. China
Xiao-Hong Zhang
Nano-Organic Photoelectronic Laboratory and Key Laboratory of Photochemical Conversion & Optoelectronic Materials, Technical Institute of Physics & Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China
Sui-Dong Wang
Institute of Functional Nano & Soft Materials (FUNSOM) & Collaborative Innovation Center of Suzhou Nano Science and Technology, Soochow University, Suzhou, Jiangsu 215123, P. R. China
The fluorescent and phosphorescent p-i-n organic light-emitting diodes (OLEDs) with well controllable compound doping have been systematically investigated, where MoO3 and LiF are the effective p-type and n-type dopants, respectively. For both the bulk and interfacial doping, the hole and electron balance in the devices is found to be strongly dependent on the doping configuration, which could either facilitate or compromise the device power efficiency. The impact of the compound doping on the charge balance is further confirmed by the change of the emission region with different doping configuration. The modulation of p-type and n-type doping densities and position is thus essential for optimizing hole and electron balance in p-i-n OLEDs.
