High Efficiency New Hole Injection Materials for Organic Light Emitting Diodes Based on Dimeric Phenothiazine and Phenoxazine Moiety Derivatives
作者:Youngil Park、Beomjin Kim、Changjun Lee、Jaehyun Lee、Ji-Hoon Lee、Jongwook Park
DOI:10.1166/jnn.2012.5886
日期:2012.5.1
New hole injection materials for organic light emitting diodes (OLEDs) based on phenothiazine and phenoxazine were synthesized, and the electro-optical properties of synthesized materials were examined by through UV-visible (UV-vis), photoluminescence (PL) spectrum and cyclic voltammetry (CV). 1-BPNA-t-BPBP and 1-BPNA-t-BPBPOX showed Tg of 127 and 200 °C, which are higher than that (110 °C) of 2-TNATA, a commercial hole injection layer (HIL) material. The highest occupied molecular orbital (HOMO) level of the synthesized materials of 1-BPNA-t-BPBP and 1-BPNA-t- BPBPOX were 4.97 and 4.91 eV, indicating values well-matched between HOMO (4.8 eV) of ITO and HOMO (5.4 eV) of NPB, hole transporting layer (HTL) material. As a result of using the synthesized materials in OLED device as HIL, 1-BPNA-t-BPBPOX of 2.43 lm/W was higher than 2-TNATA of 1.98 lm/W and 1-BPNA-t-BPBP of 1.39 lm/W in power efficiency. These results indicated that 1-BPNA-t-BPBPOX shows higher excellent power efficiency which is about 18% improved over 2-TNATA a commercial HIL material.
基于苯噻嗪和苯氧咽的新型孔注入材料被合成,并通过紫外-可见光谱(UV-vis)、光致发光(PL)光谱和循环伏安法(CV)研究了合成材料的电光特性。1-BPNA-t-BPBP和1-BPNA-t-BPBPOX的玻璃化转变温度(Tg)分别为127 °C和200 °C,高于商业孔注入层(HIL)材料2-TNATA的110 °C。合成材料1-BPNA-t-BPBP和1-BPNA-t-BPBPOX的最高占据分子轨道(HOMO)能级分别为4.97 eV和4.91 eV,表明与ITO的HOMO(4.8 eV)和孔传输层(HTL)材料NPB的HOMO(5.4 eV)有良好的匹配。作为HIL在OLED器件中使用合成材料后,1-BPNA-t-BPBPOX的功率效率为2.43 lm/W,高于2-TNATA的1.98 lm/W和1-BPNA-t-BPBP的1.39 lm/W。这些结果表明,1-BPNA-t-BPBPOX表现出更高的功率效率,约比商业HIL材料2-TNATA提高了18%。