一种基于蓝色荧光与磷光敏化技术的高显色指数白光有机电致发光器件的制备

通过采用4,4'-bis(9-ethyl-3-carbazovinylene)-1,1'-biphenyl (BCzVBi)为蓝色荧光发光单元,绿色磷光材料fac tris(2-phenylpyridine) iridium 敏化红色荧光材料4-(dicyanomethylene)-2-tert-butyl-6-(1,1,7,7-tetramethyljulolidin-4-yl-vinyl)-4H-pyran (DCJTB)为混合黄色发光单元,制备了一组白光有机电致发光器件。通过对染料掺杂浓度的优化,以及引入适当厚度的4,4-N,N-dicarbazole-biphenyl (CBP)作为中间层,获得了高效率、高显色指数的白光有机电致发光器件。器件在100 cd/m²亮度下的最高显色指数达到了90,此时的色坐标为(0.32,0.32), 非常接近白光等能点。该组器件的最大电流效率达到了11.00 cd/A,相应器件的最大亮度为13 330 cd/m²。

White Organic Light-emitting Diodes with High Color Rendering Index Using Phosphorescent Sensitizer and Blue Fluorescent Emitter

We report white organic light-emitting devices (WOLEDs) based on blue fluorescent and yellow phosphor-sensitized-fluorescent emission. In the devices, 4,4'-bis(9-ethyl-3-carbazovinylene)-1,1'-bipheny (BCzVBi) acts as a blue emitter, and 4-(dicyanomethylene)-2-tert-butyl-6-(1,1,7,7-tetramethyljulolidin-4-yl-vinyl)-4H-pyran (DCJTB) sensitized by a phosphorescent material, fac tris(2-phenylpyridine) iridium [Ir(ppy)3], acts as a mixed yellow light-emitting layer. By optimizing the doping concentration of dyes and introducing an interlayer, efficient WOLEDs with high color rendering index (CRI) values are obtained. In particular, one device shows a very high CRI value of 90 with a Commission Internationale De l'Eclairage coordinates of (0.32,0.32) at 100 cd/m2. The maximum current efficiency of the WOLEDs is 11.00 cd/A and the highest brightness of the device is 13 330 cd/m2.