Solution-processed emission layer of organic light-emitting diodes (OLEDs), especially blue OLEDs, are generally inefficient. In this work, we use an alcohol-soluble amphiphilic polymer, Poly[9, 9- bis[3- (ethyldimethylammoni o) propyl] 9′, 9′- dioctyl[2, 2′- bi- 9 H- fluorene] - 7, 7′- diyl bromide (1:2)] (PFN-Br), to modify the hole transport layer, which is deposited on the surface of Poly(9-vinyl carbazole) (PVK) layer for interface modification to achieve high efficient blue OLEDs based on the thermally activated delayed fluorescent (TADF) material 10-[4-(4,6-Diphenyl-1,3,5-triazin-2-yl)− 2-methylphenyl]-spiro[acridine-9(10 H),9’-[9 H]fluorene] (TTSA) as the emitter. It is shown that adding PFN-Br layer can reduce the defect density at the interface between PVK and the emission layer, then the exciton quenching of TTSA is reduced. After optimizing the thickness of PFN-Br layer, the maximum external quantum efficiency and current efficiency of the optimal OLED achieve 22% and 42 cd/A, respectively. To the best of our knowledge, these values are superior to the highest values reported for this material in the literature.

有机发光二极管 (OLED)，尤其是蓝色 OLED 的溶液处理发射层通常效率低下。在这项工作中，我们使用醇溶性两亲聚合物 Poly[9, 9-bis[3- (ethyldimethylammoni o) propyl] 9', 9'- dioctyl[2, 2'- bi- 9 H- fluorene] - 7, 7'-溴化二溴 (1:2)] (PFN-Br), 用于修饰空穴传输层, 沉积在聚 (9-乙烯基咔唑) (PVK) 层表面进行界面修饰, 以实现高基于热激活延迟荧光 (TADF) 材料 10-[4-(4,6-Diphenyl-1,3,5-triazin-2-yl)− 2-methylphenyl]-spiro[acridine-9( 10 H),9'-[9 H]芴] (TTSA) 作为发射体。结果表明，加入PFN-Br层可以降低PVK与发射层界面处的缺陷密度，从而降低TTSA的激子猝灭。优化PFN-Br层厚度后，最佳OLED的最大外量子效率和电流效率分别达到22%和42 cd/A。据我们所知，这些值优于文献中报道的该材料的最高值。