Terphenyl compounds are a class of aromatic hydrocarbons composed of three benzene rings. According to the different positions of the three benzene rings, terphenyls can be divided into ortho-terphenyl, meta-terphenyl and para-terphenyl. Among them, terphenyl is the most widely used. Terphenyl derivatives have large π bonds, which provide a channel for the transport of carriers, and can be used as semiconductor materials to transport holes or electrons. Terphenyl has multiple modification points, and the carrier transport ability can be regulated by introducing electron withdrawing groups or electron donating groups. In addition, further expanding the π-conjugated system of terphenyl can improve the stability of the material. Therefore, terphenyl derivatives have good chemical, electrochemical, and photochemical stability, and also have high-efficiency carrier transport capabilities, which improve the stability and conversion efficiency of optoelectronic devices as semiconductor materials.
Figure 1. Chemical structures of para-terphenyl
- Luminous material: Terphenyl is an important class of organic light-emitting materials due to it can generate fluorescence under radiation excitation. The introduction of some substituents that can cause the shift of π-conjugated electrons into the terphenyl chain can make the excitation radiation wavelength blue-shift or red-shift, and obtain rich color emission. Functionalized terphenyl derivatives have excellent luminescence properties, strong stability and solubility, and can be prepared into organic light-emitting devices with high quantum yield.
- Liquid crystal material: Terphenyl is a mesogen with a rod-like structure. The terphenyl derivatives prepared by introducing substituents into the terphenyl conjugated system are excellent liquid crystal materials, which have the advantages of excellent photostability, excellent chemical stability, and tunable anisotropy. Terphenyl is a bulky group. Connecting terphenyl with other conjugated groups can reduce the formation of exciplexes and improve the exciton transport ability of the liquid crystal material itself. Therefore, terphenyl derivatives can prepare light, thin, low power consumption, and good integrated circuit matching liquid crystal materials.
- Lingmei Kong, Frederick Chesneau, Zhengzheng Zhang, Florian Staier, Andreas Terfort, P. A. Dowben, Michael Zharnikov. Electronic Structure of Aromatic Monomolecular Films: The Effect of Molecular Spacers and Interfacial Dipoles [J]. J. Phys. Chem. C, 2011, 115, 45, 22422–22428.