1072145-30-2Relevant academic research and scientific papers
Oxadiazole based bipolar host materials employing planarized triarylamine donors for RGB PHOLEDs with low efficiency roll-off
Kautny, Paul,Lumpi, Daniel,Wang, Yanping,Tissot, Antoine,Bintinger, Johannes,Horkel, Ernst,Stoeger, Berthold,Hametner, Christian,Hagemann, Hans,Ma, Dongge,Froehlich, Johannes
, p. 2069 - 2081 (2014/03/21)
A series of 6 novel triarylamine-containing oxadiazole compounds (o-PCzPOXD, o-ICzPOXD, o-TPATOXD, o-PCzTOXD, o-ICzTOXD, o-CzTOXD) have been designed, synthesized and characterized concerning applications as host materials in PHOLED devices. To further improve the ortho-linkage concept, the impact of incorporating planarized electron-donating triarylamine (TAA) structures on intramolecular charge transfer was examined. The effect was evaluated for two series of electron-accepting oxadiazole scaffolds, realizing ortho-linkage on the benzene (POXD) and the thiophene (TOXD) cores. Thermal analysis shows increased glass-transition temperatures for planarized structures indicating an improved morphological stability. A higher degree of planarization also results in significantly increased singlet and triplet energy values, revealing the impact on the intramolecular charge transfer. Employing the developed materials, red (o-TPATOXD: CEmax: 28.8 cd A -1, EQEmax: 16.9%), green (o-PCzPOXD: CEmax: 62.9 cd A-1, EQEmax: 17.1%) and blue (o-PCzPOXD: CE max: 29.8 cd A-1, EQEmax: 13.4%) devices were achieved showing remarkably low efficiency roll-off for planarized donors. Hence, this is the first report of efficient blue devices for this specific class of host materials. It is proposed that the results correlate with an increasing ortho-linkage effect and decreasing donor strength of the TAA moiety by planarization and, thus, tackling one of the major challenges in PHOLED research: improving both triplet energy and compound stability. The Royal Society of Chemistry.
Multifunctional bipolar triphenylamine/oxadiazole derivatives: Highly efficient blue fluorescence, red phosphorescence host and two-color based white OLEDs
Tao, Youtian,Wang, Qiang,Shang, Yuan,Yang, Chuluo,Ao, Liang,Qin, Jingui,Ma, Dongge,Shuai, Zhigang
supporting information; experimental part, p. 77 - 79 (2009/03/11)
Two simple triphenylamine/oxadiazole derivatives were synthesized and fully characterized; their multifunctionality as highly efficient non-doped blue fluorescence, excellent red phosphorescent host and single-doped two-color based white OLEDs has been de
