Photoredox Processes in the Aggregation and Gelation of Electron-Responsive Supramolecular Polymers Based on Viologen

Clément Roizard (1) , Vivien Andrieux (1) , Shaymaa Al Shehimy (1) , Shagor Chowdhury (1) , Quentin Reynard-Feytis (1) , Christophe Kahlfuss (1) , Eric Saint-Aman (2) , Floris Chevallier (1) , Christophe Bucher (1) , Thomas Gibaud (3) , Denis Frath (1)

1 LC - Laboratoire de Chimie - UMR5182
2 DCM - Département de Chimie Moléculaire
3 Phys-ENS - Laboratoire de Physique de l'ENS Lyon

Viologen-based ditopic bis-pyridinyl-triazole bidentate ligands self-assemble in the presence of palladium ions into supramolecular polymers whose structure is imposed by the directed formation of coordination bonds. Light-irradiation of these electronresponsive supramolecular materials triggers a photo-induced electron transfer yielding isolated π-radicals and dimers of radicals. The photoreduction events and the associated dimerization steps trigger a large-scale reorganization occurring within the supramolecular network yielding aggregates or gels depending on the irradiation conditions (power, duration). Detailed electrochemical, spectro-electrochemical and photochemical analyses were conducted to understand the mechanisms at stakes in these light-induced aggregation and gelation.

Domaines: Chimie

Clément Roizard, Vivien Andrieux, Shaymaa Al Shehimy, Shagor Chowdhury, Quentin Reynard-Feytis, et al.. Photoredox Processes in the Aggregation and Gelation of Electron-Responsive Supramolecular Polymers Based on Viologen. ECS Advances, 2022, 1 (2), pp.020502. ⟨10.1149/2754-2734/ac6ad4⟩. ⟨hal-03722425⟩