中文摘要：

采用真空热蒸发的方法制备了V_2O_5薄膜,将其引入有机发光二极管（OLED）器件中用作空穴缓冲层,制备了以4,4＇-N,N＇-二咔唑基联苯（CBP）为主体材料,Ir（ppy）2acac为绿光磷光掺杂染料的OLED器件,结构为ITO/V_2O_5/NPB/TCTA/CBP∶Ir（ppy）2acac/BCP/Alq3/Li F/Al。研究了不同厚度的V_2O_5作为空穴缓冲层对绿色磷光OLED器件发光性能的影响。结果表明,当V_2O_5薄膜的厚度为30 nm时,器件的性能最佳,其最大电流效率和最大功率效率分别为54.36 cd/A和48.77 lm/W,比未加入缓冲层的常规器件均提高了34%。在驱动电压为11 V时,亮度可达到28 990 cd/m2,且在电压从5 V上升至10 V的过程中,对应的色坐标仅从（0.36,0.60）变化为（0.36,0.61）,具有很高的稳定性。分析认为适当厚度的V_2O_5薄膜降低了发光层中空穴的浓度,提高了空穴和电子载流子的复合效率。

英文摘要：

The V205 film was prepared by vacuum thermal evaporation method as the hole buffer layer in the organic light emitting diode （OLED） device. The green phosphorescent OLED device with the structure of ITO/V20s/NPB/TCTA/CBP ： Ir （ppy） 2 aeae/BCP/Alq3/LiF/A1 was prepared. The 4, 4＇-bis （9-carbazolyl） -1, 1＇-biphenyl （CBP） was host material and Ir（ppy）2aeae was green phos- phorescent dopant. The effects of different thicknesses of V2 05 as hole buffer layer on the luminous performance of green phosphorescent OLED device were researched. The results show that when the thickness of V205 film is 30 nm, the maximum current efficiency and power efficiency are 54.36 ed/A and 48.77 lm/W, respectively, which is both 34% higher than those of the device without V205 as hole buffer layer. The luminance reaches 28 990 cd/m2 at driving voltage of 11 V. The chromaticity coordi- nates only change from （0.36, 0.60） to （0.36, 0.61） as the voltage increases from 5 V to 10 V, and it has high stability. The analysis shows that the proper thickness of V2 05 thin film reduces the concentration of holes in the light emitting layer and improves the recombination efficiency of hole and electron carriers.