Template process for engineering the photoluminescence of PVK and PPV-based nanowires

Blends or stacking layers of two complementary materials are the dominant methods to get a strong donor-acceptor behavior for in-solution-processed thin film devices. These methods result in different local arrangement of the two species, a central point for tuning the donor-acceptor. In this work, it is proposed to organize a donor (poly[vinylcarbazole], PVK) and an acceptor (poly[para-phenylenevinylene], PPV) in a nanowire geometry. A two-step template process was used to fabricate coaxial nanowires with PPV and PVK alternatively as the core or the shell material, as shown by morphological characterization and micro-Raman spectroscopy study. The differences of the photoluminescence properties of these two types of coaxial nanowires compared with those of PVK-PPV blend nanowires and of pure PPV and PVK nanowires are discussed by considering the local polymer arrangement and the exciton diffusion length. Nano-sources, as well as nanostructured light emitting diodes, could take advantage of this 1D-like morphology for light emission control. (c) 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 48201.