Photoresponsive ordered hybrid materials containing a bridged azobenzene group

This paper describes the synthesis of 4,4'-[(triisopropoxysilyl)propyloxy]azobenzene and the preparation of the ordered hybrid material containing the bridged azobenzene moieties within the framework by using the direct liquid crystal templating approach. We show that a sizable fraction of the azobenzene groups is reversibly photoisomerized though the chromophore is covalently linked to the silica matrix at both ends. In contrast, the photoisomerization did not occur in the corresponding material prepared in the absence of template. This is explained by a regular dilution of the chromophores into silica thanks to the template used for the preparation of the material.