Selected-area in situ generation of highly fluorescent organic nanowires embedded in a polymer film: the solvent-vapor-induced self-assembly process

The preparation of highly fluorescent one-dimensional (1D) nanostructures within a selected area of a solid substrate is a challenging requirement for the realization of optoelectronic nanodevices. We present a novel method for fabricating highly fluorescent organic nanowires (NWs) embedded in a variety of polymer films through the combined processes of photochemical lithography and solvent-vapor annealing (SVA). To achieve this, we designed and synthesized an acid-responsive organic fluorophore bearing a self-assembly moiety. The in situ self-assembly of this fluorophore into ultralong nanowires proceeds selectively in designated regions of the polymer matrix via a simple selected-area SVA process. The I-V electrical characteristics of 2-(3',5'-bis(trifluoromethyl)biphenyl-4-yl)-3-(6-3,5-bis(trifluoromethyl) phenyl)pyridine-3-yl)acrylonitrile (Py-CN-TFMBE) structures, self-assembled using the SVA method, were measured on a two-terminal electrode device. This unique fabrication approach, which combines photochemical lithography and SVA, eliminates the difficulties of transferring preformed 1D organic nanostructures to fixed locations on a substrate, thereby establishing a new method for the fabrication control of optoelectronic nanodevices.