Green-fluorescent naphthalene diimide: Conducting layered hierarchical 2D nanosheets and reversible probe for detection of aromatic solvents

We report the molecular engineering of asymmetrically functionalized naphthalene diimide (NDI) with a simple amino acid into robust self-assembled free-standing, green-fluorescent and conducting layered hierarchical 2D nanosheets which exhibit chiral and crystalline molecular packing. Remarkably the NDI-amino acid conjugate displays tunable fluorescence emission (wavelength range 400-540 nm) properties in aromatic solvents. Furthermore we have exploited the phenomenon of excimer to exciplex transformation to develop a filter paper-based reversible fluorometric test kit for the detection of benzene, a well-known classified carcinogen.