A series of blue-emitting triarylamines containing pyrene and hexaphenylbenzene dendrons were successfully synthesized by employing the Diels–Alder and palladium catalyzed C–N coupling reactions. They display high glass transition temperatures (>140 °C) in differential scanning calorimetry and facile reversible oxidation couple in cyclic voltammetry. They are also thermally stable exhibiting decomposition temperature above 385 °C. Efficient blue-emitting electroluminescent devices were fabricated using these novel amines as the hole transporting layer and 1,3,5-tris(N-phenylbenzimidazol-2-yl)benzene (TPBI) as the electron transporting layer. Colour mixing or green emission was observed when tris(8-hydroxyquinoline)aluminium (Alq3) was used as the electron transporting layer. However insertion of a thin layer of TPBI or 1,3,5-tris(4-tert-butylphenyl-1,3,4-oxadiazolyl)benzene (TPOB) in between the HTL and Alq3 layers led to pure blue emission owing to the confinement of recombination inside the HTL layer containing the compounds.
一系列含有
芘和
六苯基苯树枝状结构的蓝光发射
三芳胺通过采用Diels–Alder反应和
钯催化的C–N偶联反应成功合成。它们在差示扫描量热法中显示出高
玻璃转变温度(>140 °C),并且在循环伏安法中表现出简便的可逆氧化耦合。它们还具有热稳定性,分解温度超过385 °C。使用这些新型胺作为空穴传输层,1,3,5-三(N-苯基
苯并咪唑-2-基)苯(TPBI)作为电子传输层,制备了高效的蓝光发射电致发光器件。使用三(
8-羟基喹啉)铝(Alq3)作为电子传输层时,观察到颜色混合或绿色发射。然而,在HTL层和Alq3层之间插入一层薄的TPBI或1,3,5-三(4-
叔丁基苯基-
1,3,4-噁二唑基)苯(TPOB)导致了纯蓝光发射,这归因于在含有化合物的HTL层内的再组合限制。