Photocontrollable Supramolecular Self-Assembly of a Porphyrin Derivative that Contains a Polyhedral Oligomeric Silsesquioxane (POSS)

Graphical Hugo POSS : A photosensitive organic–inorganic hybrid porphyrin (H 2 TPP−Azo−POSS) exhibited a tunable morphology by simply changing the concentration and polarity of the solvent. Spherical micelles and linear nanowires were formed in CHCl 3 , whilst vesicles were formed in CHCl 3 / n -hexane. The morphologies of H 2 TPP−Azo−POSS demonstrated a light-triggered transition, whilst the size of the aggregates decreased under UV irradiation. In this study, we have synthesized a new photosensitive organic–inorganic POSS-containing hybrid porphyrin derivative (H 2 TPP−Azo−POSS), in which azobenzene was used as a bridge to conjugate the porphyrin and POSS, by using click chemistry. The self-assembly behavior of H 2 TPP−Azo−POSS was studied at different concentrations in CHCl 3 and in CHCl 3 / n -hexane mixed solvent systems. Our results showed that the self-assembled morphology of H 2 TPP−Azo−POSS could be tuned by varying the concentration and polarity of the solvent. Spherical micelles and linear nanowires could be obtained in CHCl 3 , whilst vesicles could be formed in CHCl 3 / n -hexane mixtures with low polarities. The supramolecular self-assembled morphologies of H 2 TPP−Azo−POSS demonstrated a light-triggered transition behavior, whilst the size of the assembled aggregates decreased significantly under UV irradiation.