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A charge generation layer(CGL) of Liq/Al/HAT-CN is used to fabricate the blue-yellow complementary tandem white organic light-emitting device. A group of dual-color devices are used to illustrate the working mechanism of CGL, and Liq/Al structure in the CGL is further studied. Under the current density of 10 mA/cm2, the operating voltage(8.3 V) and luminance(746 cd/m2) of the tandem device are both approximately the sum of those of blue device(4.2 V, 315 cd/m2) and yellow device(4.2 V, 426 cd/m2), respectively, confirming that the charge generating layer is effective. The maximum brightness of 11 420 cd/m2 is obtained at the current density of 240 mA/cm2, and the current efficiency and power efficiency are 7.2 cd/A and 2.6 lm/W under the luminance of 1 000 cd/m2, respectively. When driving current density increases from 10 mA/cm2 to 30 mA/cm2, the ratio of blue light in spectra increases by 5%, which means the stable performance of device. In view of the weak microcavity effect existing in the tandem device, we conducted in-depth research by optical simulation based on the microcavity theory. The simulation results are highly consistent with the actual spectra, demonstrating the accuracy of optical simulation calculation.

以B3PyMPM：Cs/Al/HAT-CN作为电荷生成单元制备高效叠层绿色磷光有机电致发光器件，叠层器件的最大电流效率和最大流明效率分别为172.2 cd/A和111.0 lm/W，在5 mA/cm2电流密度下，叠层器件的电压和亮度分别为传统器件的2.04倍和2.84倍.为了探究叠层器件性能优于传统器件的原因，研究了电荷生成单元内的电荷产生和注入过程，以及薄层铝对电子注入特性和电荷生成单元稳定性的影响.实验结果表明，电荷能够有效地在电荷生成单元内产生并顺利注入电子传输层中，B3PyMPM：Cs和HAT-CN间Al薄层的插入能够进一步提高电子注入效率及器件结构的稳定性.