Liu Yiming, Niu Tingting, Wang Jinpei, Li Yajing, Meng Na, Yu Bufan, Shi Xiaorong, Xu Kui, Chen Jiangshan, Ma Dongge, Xia Yingdong, Guo Qingxun, Chen Yonghua
Key Laboratory of Flexible Electronics (KLoFE) & Institute of Advanced Materials (IAM), School of Flexible Electronics (Future Technologies), Nanjing Tech University (NanjingTech), 30 South Puzhu Road, Nanjing 211816, People's Republic of China.
Institute of Polymer Optoelectronic Materials and Devices, State Key Laboratory of Luminescent Materials and Devices, South China University of Technology, Guangzhou 510640, People's Republic of China.
Nano Lett. 2024 Sep 4;24(35):10972-10979. doi: 10.1021/acs.nanolett.4c02910. Epub 2024 Aug 23.
Metal halide perovskites hold great potential for next-generation light-emitting diodes (PeLEDs). Despite significant progress, achieving high-performance PeLEDs hinges on optimizing the interface between the perovskite crystal film and the charge transport layers, especially the buried interface, which serves as the starting point for perovskite growth. Here, we develop a bottom-up perovskite film modulation strategy using formamidine acetate (FAAc) to enhance the buried interface. This multifaceted approach facilitates the vertical-oriented growth of high-quality perovskites with minimized defects. Meanwhile, the in situ deprotonation between FA and ZnO could eliminate the hydroxyl (-OH) defects and modulate the energy level of ZnO. The resulting FAPbI-PeLED exhibits a champion EQE of 23.84% with enhanced operational stability and suppressed EQE roll-off. This strategy is also successfully extended to other mixed-halide PeLEDs (e.g., CsFAPb(IBr)), demonstrating its versatility as an efficient and straightforward method for enhancing the PeLEDs' performance.
