The incorporation of TiO2 nanoparticles into long (several micrometers) fibers of a gel-forming poly(para-phenylene vinylene) (PPV) derivative is described. For that purpose, a PPV-block-dopamine polymer is synthesized, which is used to coat TiO2 nanoparticles leading to well-dispersed nanoparticles and fluorescence quenching of the polymer. Independently, the homopolymer gels in various organic solvents are observed to form long fibers. By mixing the PPV homopolymer with the TiO2-PPV hybrid, we are able to incorporate the nanoparticles into the fibrous network, as shown in transmission electron microscopy (TEM) images. Photoinduced charge separation is measured by Kelvin probe force microscopy. Upon illuminating the polymer fibers, positive charges are observed, even at distances of around 300 nm. From these results, charge transport along the polymer fibers is inferred.
zur Borg, Lisa, Anna L. Domanski, Rudiger Berger, Rudolf Zentel
Macromol. Chem. Phys.