標題: ZnO nanocrystals incorporating PEIE and a fluorene-based polyelectrolyte as electron transport layers for pure cesium-containing perovskite light-emitting devices
作者: Chang, Chun-Jung
Yang, Sheng-Hsiung
照明與能源光電研究所
Institute of Lighting and Energy Photonics
關鍵字: perovskite;inverted light-emitting devices;polyethyleneimine ethoxylated;ionic polyfluorene;ZnO nanocrystals
公開日期: 1-十月-2019
摘要: In this work, we demonstrate inverted perovskite light-emitting devices (PeLEDs) based on ZnO nanocrystals (NCs) and cesium lead bromide (CsPbBr3) film as the electron transport and emission layers, respectively. Polyethyleneimine ethoxylated (PEIE) and an ionic polyfluorene derivative containing trimethylammonium hexafluorophosphate groups (namely P2-PF6) were introduced between ZnO NCs and CsPbBr3 film. The introduction of the PEIE/P2-PF6 bilayer decreased the work function of ZnO NCs to achieve balanced charge injection into the emission layer. Furthermore, the bilayer also effectively improved CsPbBr3 coverage and morphology, thereby reducing current leakage in PeLEDs. The improved CsPbBr3 film showed better photoluminescence, owing to anti-quenching capability of the PEIE/P2-PF6 and prolonged carrier lifetime. PeLEDs with the structure ITO/ZnO NCs/ PEIE/P2-PF6/CsPbBr3 film/poly(9,9-dioctylfluorene-co-N-(4-butylphenyl)diphenyl amine) (TFB)/Au were fabricated and evaluated, employing TFB as the hole transport layer. The PeLED based on the PEIE/P2-PF6 showed a turn-on voltage of 2.8 V, a max luminance of 3,927 cd m(-2) and max current efficiency of 0.2 cd A(-1) that was significantly higher than those without PEIE/P2-PF6 bilayer.
URI: http://dx.doi.org/10.1088/2053-1591/ab34d0
http://hdl.handle.net/11536/152591
ISSN: 2053-1591
DOI: 10.1088/2053-1591/ab34d0
期刊: MATERIALS RESEARCH EXPRESS
Volume: 6
Issue: 10
起始頁: 0
結束頁: 0
顯示於類別:期刊論文