Unprecedented light induced aggregation of cationic 1,4,5,8-naphthalenediimide amphiphiles

Antoneli, Rafael G.; Moraes, Thaisa B. F.; Junqueira, Helena C.; Sihn, Luca M.; Toma, Henrique E.; Pedras, Bruno; Ferreira, Luís F. V.; Frath, Denis; Bucher, Christophe; Steed, Jonathan W.; Demets, Gregóire J.-F.; Triboni, Eduardo R.

Abstract

Bola amphiphiles from naphthalenediimide (NDI-bas) with quaternary ammonium groups (DC4, DaP, and DaO) display association in solution, as well as, surprisingly, visible light promoted photochromism in concentrated solutions of water, acetonitrile and THF. The photochromism is correlated with an aggregation process that leads to a significant modification of the electronic transitions, resulting in an unusual absorption band distribution that points out to a type of H-aggregation in transverse. This assembly can be reversibly broken up by heating at 70 °C and adding bulk salt (NaBF4). By 1H-NMR spectroscopic analysis of the irradiation/heating cycle the assembly/disassembly process can be followed by the changes in peak width and intensity. These photoinduced aggregates can sensitize dissolved O2 to give singlet oxygen, a surprising observation when it comes to sensitization efficiency for dyes where aggregation usually decreases the sensitization yield. Laser-induced luminescence measurements corroborate the existence of triplet states as phosphorescence was detected, being particularly intense in concentrated THF solutions.

Citation

Antoneli, R. G., Moraes, T. B. F., Junqueira, H. C., Sihn, L. M., Toma, H. E., Pedras, B., Ferreira, L. F. V., Frath, D., Bucher, C., Steed, J. W., Demets, G. J.-F., & Triboni, E. R. (2024). Unprecedented light induced aggregation of cationic 1,4,5,8-naphthalenediimide amphiphiles. Journal of Materials Chemistry C Materials for optical and electronic devices, 12(11), 3888-3896. https://doi.org/10.1039/d3tc04178f

• Journal Article Type: Article
• Acceptance Date: Feb 21, 2024
• Online Publication Date: Feb 23, 2024
• Publication Date: Mar 21, 2024
• Deposit Date: Aug 8, 2024
• Publicly Available Date: Aug 8, 2024
• Journal: Journal of Materials Chemistry C
• Print ISSN: 2050-7526
• Electronic ISSN: 2050-7534
• Publisher: Royal Society of Chemistry
• Peer Reviewed: Peer Reviewed
• Volume: 12
• Issue: 11
• Pages: 3888-3896
• DOI: https://doi.org/10.1039/d3tc04178f
• Public URL: https://durham-repository.worktribe.com/output/2744376