Work

Unraveling the positive effect of twisted helicene structure on narrowband electroluminescence

Year: 2026

Type: article

Abstract: π-extension of a classic MR backbone (CzBN) and disclose how the twisted structure plays a positive role in reducing the emission bandwidth. Specifically, π-extension of CzBN to form a [5]helicene substructure (BN-5H) induces serious vibrations, while further extending the helicene moiety to build a [7]helicene substructure (BN-7H) suppresses undesirable vibrations by locking the conformation. As a consequence, BN-7H achieves a smaller full-width at half-maximum (FWHM) of 28 nm compared with BN-5H (33 nm) in organic light-emitting diodes and longer device lifetime. These results overturn the traditional cognition of the detrimental effect of highly twisted structures on narrowband emission and offer a new design concept for the future development of narrowband electroluminescence materials.

Source: Chemical Science

DOI: 10.1039/d5sc08405a