Peripherally Modified Tetraphenylethene: Emerging as a Room-Temperature Luminescent Disc-Like Nematic Liquid Crystal

ACS Appl Mater Interfaces. 2021 Jul 28;13(29):35207-35213. doi: 10.1021/acsami.1c10243. Epub 2021 Jul 19.

Abstract

A blue-light-emitting liquid crystalline (LC) material was designed and prepared. By employing a twisted luminescent core (i.e., tetraphenylethene), four peripheral LC units with long alkyl chains and the small polar benzyl-ether-typed linking groups, the resulting material displayed a hexagonal columnar phase near room temperature and a disc-like nematic phase between 32 and 70 °C. The columnar LC showed a high quantum yield of 0.49 at 20 °C, and the efficient luminescence property was retained even in the isotropic phase at high temperature. Additionally, the fluidity of the nematic phase rendered the LC a non-volatile solvent, and the proper addition of a red dye led to the achievement of polarized white-light emission, which revealed a promising application prospect in LC display fabrication.

Keywords: aggregation-induced emission; disc-like nematic phase; phase transition; room-temperature liquid; white-light emission.