s-Tetrazine-Bridged Photochromic Aromatic Framework Material

Y Integrating fluorescent chromophores in aromatic frameworks could not only prevent aggregation-induced quenching caused by the p-p stacking interaction between the chromophore components but also confer new fluorescence properties. Herein, we report the fabrication of s-tetrazine-bridged aromatic frameworks TzAF by the incorporation of the smallest aromatic fluorophore, s-tetrazine (Tz), into the skeleton of a tetrahedrally connected lattice of aromatic frameworks. The thin films of TzAF coated on silica gel plates were found to exhibit reversible photoswitching fluorescence characteristics under alternate UV and visible-light irradiations with excellent fluorescence stability and high on/off contrast. The repeatable on/offfluorescence photoswitchability of the TzAF thin films was mechanistically attributed to light-induced reversible transformation between TzAF's neutral and radical states.

Automated summary

Integrating fluorescent chromophores into aromatic frameworks can prevent aggregation-induced quenching and impart new fluorescence properties. In this study, s-tetrazine-bridged aromatic frameworks (TzAF) were fabricated by incorporating the smallest aromatic fluorophore, s-tetrazine (Tz), into the lattice of aromatic frameworks. The TzAF thin films exhibited reversible photoswitching fluorescence characteristics with excellent stability and high on/off contrast due to light-induced reversible transformation between TzAF's neutral and radical states.