Hybrid gels assembled from Fmoc-amino acid and graphene oxide with controllable properties

A supramolecular gel is obtained from the self-assembly of an ultralow-molecular-weight gelator (N-fluorenyl-9-methoxycarbonyl glutamic acid) in good and poor solvents. The gelators can self-assemble into a lamellar structure, which can further form twisted fibers and nanotubes in the gel phase. Rheological studies show that the gels are robust and rigid, and are able to rapidly self-recover to a gel after being destroyed by shear force. Fluorescence experiments reveal the aggregation-induced emission effects of the gel system; the fluorescence intensity is significantly enhanced by gel formation. Graphene oxide (GO) is introduced into the system efficiently to give a hybrid material, and the interaction between gelators-GO sheets is studied. Rheological and fluorescent studies imply that the mechanical properties and the fluorescent emission of the hybrid materials can be fine-tuned by controlling the addition of GO.