Synthesis of a highly phosphorescent emitting iridium(III) complex and its application in OLEDs

High-efficient phosphorescent iridium(III) complexes with benzimidazole ligand for organic light-emitting diodes: Synthesis, electrochemistry and electroluminescent properties

“…Similar result was observed for complex Ir(FFBI) 2 (pti). For many luminescent organic molecules, the absorption spectrum overlaps on the emission spectrum, especially for heavy metal complexes due to their metal to ligand charge transfer (MLCT) [11]. Based on the wavelengths at which the UV-Vis absorption and photoluminescent spectra intersect, the energy gap between LUMO and HOMO can be calculated.…”

“…Therefore, design of ligands for Ir complexes is of great importance in order to achieve high efficiency and color purity for OLEDs. To date, most researches were focused on the design and synthesis of the cyclometalated ligand, such as changing p conjugation, introducing electron donating or withdrawing group on the appropriate position of the aromatic ring [7][8][9][10], and adopting rigid structure, as we recently reported [11], to get high efficient and full-color emitting materials, while the study to the ancillary ligand was deficient though it was shown that the ancillary ligand has an evident effect on the properties of materials [12][13][14]. And also, a majority of complexes obtained by modifying cyclometalated ligand emit green or red color, while blue-emitting iridium complexes, which are important for the realization of RGB full-color displays and the creation of white light-emitting devices (WOLEDs), are still scarce.…”

Naphthalene Benzimidazole Based Neutral Ir(III) Emitters for Deep Red Organic Light-Emitting Diodes

“…13−15 In this regard, phenyl-benzimidazole and its derivatives can be an alternative source for the construction of efficient iridium emitters. 24,25 Similar to the traditional method, the emission color of the emitter can be easily tuned by incorporating electron-donating/-withdrawing groups into the benzimidazole and phenylene units (Figure 1). In particular, whereas greenand red-emitting OLEDs have been relatively well developed, 26−33 deep red and near-IR (NIR) emissive materials are still in their early developmental stage.…”

“…In this regard, phenyl-benzimidazole and its derivatives can be an alternative source for the construction of efficient iridium emitters. , Similar to the traditional method, the emission color of the emitter can be easily tuned by incorporating electron-donating/-withdrawing groups into the benzimidazole and phenylene units (Figure ). In particular, whereas green- and red-emitting OLEDs have been relatively well developed, − deep red and near-IR (NIR) emissive materials are still in their early developmental stage. − Recently, Pt­(II)- and Os­(II)-based emitters were used to develop NIR OLEDs with high efficiency and low efficiency roll-off. − The extension of an aromatic unit or the introduction of electron-withdrawing groups to the benzimidazole moiety will help in the stabilization of the lowest unoccupied molecular orbital (LUMO) level.…”

A novel series of iridium complexes with alkenylquinoline ligands: Theoretical study on electronic structure and spectroscopic property

“…On experiment, since it was reported that OLEDs prepared with Ir(ppy) 3 (ppy = 2-phenylpyridine) have greater efficiencies more than 80%, Ir(III) complexes have attracted much more attention [9][10][11][12][13][14][15][16][17][18][19][20]. Numerous homoleptic and heteroleptic cyclometalated Iridium complexes, emitting from blue to red, such as Ir(C^N) 3 , Ir(C^N) 2 L, and IrLL' have been synthesized and their spectral properties have been investigated by Thompson [9,10,21], Collin [22,23], and Slugovc [24] experimentally.…”