Jayabharathi Jayaraman, Ramya Ramaiyan, Thanikachalam Venugopal, Jeeva Palanivel, Sarojpurani Elayaperumal
Department of Chemistry, Annamalai University Annamalai Nagar Tamilnadu 608 002 India.
Sri Manakula Vinayagar Engineering College India.
RSC Adv. 2019 Jan 23;9(6):2948-2966. doi: 10.1039/c8ra09486a. eCollection 2019 Jan 22.
A series of efficient blue-emitting materials, namely, Cz-DPVI, Cz-DMPVI, Cz-DEPVI and TPA-DEPVI, possessing a donor-acceptor architecture with dual carrier transport properties and small singlet-triplet splitting is reported. These compounds exhibit excellent thermal properties with a very high glass-transition temperature ( ), and thus, a stable uniform thin film was formed during device fabrication. Among the weak donor compounds, specifically, Cz-DPVI, Cz-DMPVI and Cz-DEPVI, the Cz-DEPVI-based device showed the maximum efficiencies (: 13 955 cd m, : 4.90%, : 6.0 cd A, and : 5.4 lm W) with CIE coordinates of (0.15, 0.06) at 2.8 V. The electroluminescent efficiencies of Cz-DEPVI were higher than that of the strong donor TPA-DEPVI-based device (: 13 856 cd m, : 4.70%, : 5.7 cd A, and : 5.2 lm W). Furthermore, these blue emissive materials were used as hosts to construct efficient green and red phosphorescent OLEDs. The green device based on Cz-DEPVI:Ir(ppy) exhibited the maximum of 8891 cd m, of 19.3%, of 27.9 cd A and of 33.4 lm W with CIE coordinates of (0.31, 0.60) and the red device based on Cz-DEPVI:Ir(MQ)(acac) exhibited the maximum of 40 565 cd m, of 19.9%, of 26.0 cd A and of 27.0 lm W with CIE coordinates of (0.64, 0.37).
报道了一系列高效蓝光发射材料，即Cz-DPVI、Cz-DMPVI、Cz-DEPVI和TPA-DEPVI，它们具有供体-受体结构，具有双载流子传输特性且单线态-三线态分裂小。这些化合物表现出优异的热性能和非常高的玻璃化转变温度（ ），因此，在器件制造过程中形成了稳定均匀的薄膜。在弱供体化合物中，特别是Cz-DPVI、Cz-DMPVI和Cz-DEPVI，基于Cz-DEPVI的器件在2.8 V时表现出最大效率（ ：13955 cd m， ：4.90%， ：6.0 cd A， ：5.4 lm W），CIE坐标为(0.15, 0.06)。Cz-DEPVI的电致发光效率高于基于强供体TPA-DEPVI的器件（ ：13856 cd m， ：4.70%， ：5.7 cd A， ：5.2 lm W）。此外，这些蓝光发射材料被用作主体来构建高效的绿色和红色磷光有机发光二极管。基于Cz-DEPVI:Ir(ppy)的绿色器件表现出最大 为8891 cd m， 为19.3%， 为27.9 cd A， 为33.4 lm W，CIE坐标为(0.31, 0.60)，基于Cz-DEPVI:Ir(MQ)(acac)的红色器件表现出最大 为40565 cd m， 为19.9%， 为26.0 cd A， 为27.0 lm W，CIE坐标为(0.64, 0.37)。
