Influence of morphology on the emissive properties of dye-doped PVP nanofibers produced by electrospinning

Dye-doped polymer micro- and nanofibers with tailored light emission properties have great potential for applications in optical, optoelectronic, or photonic devices. In this study, these types of structures were obtained by electrospinning rhodamine 6 G-doped polyvinylpyrrolidone (PVP) using a polymer solution of 10% (mass) concentration in ethanol. Polymer nanofibers with different morphologies (smooth and beaded) and diameters of about 500 nm were obtained using different electrospinning conditions with the same solutions. Fluorescence optical microscopy observations showed that the dye was distributed uniformly in the doped PVP nanofibers. Different shifts were observed when we compared the wavelength of the dye emission band peak of the smooth nanofibers (566 nm) and the wavelength of the dye emission band peak of the beaded fibers (561.5 nm) produced by electrospinning in different conditions with the wavelength of the emission band peak for transparent thin films produced by spin coating (558 nm) using the same polymer solution. This demonstrates that it is possible to tune the optical properties of electrospun dye-doped polymer nanofibers simply by modifying the morphology of the material, i.e., the parameters of the electrospinning process.