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arXiv · 2203.12508

Photoredox Processes in the Aggregation and Gelation of Electron-responsive Supramolecular Polymers Based on Viologens

Clément Roizard·Vivien Andrieux·Shagor Chowdhury·Quentin Reynard-Feytis·Christophe Kahlfuss·Eric Saint-Aman·Floris Chevallier·Christophe Bucher·Thomas Gibaud·Denis Frath
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Abstract

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 electron-responsive supramolecular materials triggers a photo-induced electron transfer yielding isolated {\pi}-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.

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Clément Roizard, Vivien Andrieux, Shagor Chowdhury, Quentin Reynard-Feytis, Christophe Kahlfuss, Eric Saint-Aman, Floris Chevallier, Christophe Bucher, Thomas Gibaud, Denis Frath. 2022-03-23. Photoredox Processes in the Aggregation and Gelation of Electron-responsive Supramolecular Polymers Based on Viologens. https://arxiv.org/abs/2203.12508

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