Stimuli-responsive organogels based on a gelator of hydrazide and azobenzene units connected via a flexible central spacer

An organogelator named 1-[4-(4′-dodecyloxyphenylazo)phenoxy]-5- [(N-(4-nitrobenzoyl) -N′-(benzoyl-4′-oxy)hydrazine)] pentane (EN) formed stable organogel in THF. SEM image revealed that the xerogels consisted of clumped spheroids, within which molecules self-assembled to a layered structure. Both intermolecular hydrogen bonding and π-π stacking interactions were confirmed to be responsible for the self-assembly processes and the gel formation. In addition, organogel of EN exhibited multiple stimuli-responsive behaviors upon exposure to stimuli such as temperature, light, and anion. The effect of flexible central spacer on the trans-cis photoisomerization of the azobenzene moiety was demonstrated.

Graphical abstractDownload high-res image (209KB)Download full-size imageThe organogel based on a gelator of hydrazide and azobenzene units connected via a flexible central spacer exhibited a layer structure, and this organogel exhibited multiple stimuli-responsive behaviors upon exposure to stimuli such as temperature, light, and anion.