Ricerc@Sapienza

Development of polyvinylidene fluoride (PVDF) film composite filled with carbon-based nanomaterials is attracting considerable attention in engineering applications. Numerous studies focus on the enhancement of PVDF properties by adding chemically modified graphene oxide or functionalized carbon nanotubes, or by modifying the polymer chains. On the other hand, in this paper we investigate the nucleation effect of graphene nanoplatelets (GNPs) on morphology and structure of PVDF, without any chemical modification or functionalization either of the GNPs or of the polymer chains.

In this work, we present the optoelectronic characterization of pure tungsten oxide nanoparticle networks synthesized and self-assembled by flame spray pyrolysis. Current-voltage measurements performed in dark conditions indicate the presence of trapping and de-trapping phenomena from defects inside the energy gap. The presence of defects is confirmed by the time evolution of the photocurrent, measured under monochromatic radiation at 420 nm. After illuminating the WO3 films with light, the current increases exponentially with a time constant independent on the applied voltage.