Room-temperature discotic liquid-crystalline coronene diimides exhibiting high charge-carrier mobility in air
作者:Zesheng An、Junsheng Yu、Benoit Domercq、Simon C. Jones、Stephen Barlow、Bernard Kippelen、Seth R. Marder
DOI:10.1039/b910898j
日期:——
Six N,N′,5,11-tetrasubstituted coronene-2,3,8,9-tetracarboxydiimides have been synthesised incorporating 3,4,5-tri(n-dodecyloxy)phenyl or 2-(n-decyl)-n-tetradecyl groups in various positions. Differential scanning calorimetry, polarised optical microscopy, and X-ray diffraction indicate that all form columnar discotic mesophases from around room temperature to around 200 °C. Charge-carrier mobility values, which energetic considerations suggest are electron mobility values, have been determined in non-aligned samples cooled from the isotropic melt using the space-charge-limited current technique. The highest mobility, 6.7 cm2V−1 s−1, was found in N,N′-bis(n-2,2,3,3,4,4,5,5,6,6,7,7,8,8,8-pentadecylfluorooctyl)-5,11-bis(3-[3,4,5-tri(n-dodecyloxy)phenyl}carbonyloxy]-n-propyl)coronene-2,3,8,9-tetracarboxydiimide, which X-ray diffraction suggests is the most highly ordered of the materials examined.
已合成六种N,N′,5,11-四取代的二萘-2,3,8,9-四羧二亚胺,分别在不同位置引入了3,4,5-三(n-十二烷氧基)苯基或2-(n-癸基)-n-十四烷基团。差示扫描热量测量、偏振光学显微镜和X射线衍射表明,这些化合物在近室温到约200°C的范围内均形成柱状盘状介相。通过空间电荷限制电流技术,在从各向同性熔体冷却的非对齐样品中测定了载流子迁移率值,热力学考虑表明这些值是电子迁移率的值。最高迁移率为6.7 cm²V⁻¹ s⁻¹,出现在N,N′-双(n-2,2,3,3,4,4,5,5,6,6,7,7,8,8,8-十五烷基氟辛基)-5,11-双(3-[3,4,5-三(n-十二烷氧基)苯基}羧氧]-n-丙基)二萘-2,3,8,9-四羧二亚胺中,X射线衍射表明这是所研究材料中有序度最高的。