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A combination of the remarkably simple technique of electrospinning, developed to fabricate polymer nanofibers, and sol–gel processing has been utilized to produce fine zinc oxide nanofibers with an average diameter of 70 nm. A non-toxic precursor solution of polyvinyl alcohol and zinc acetate was electrospun and the resulting fibers were then calcined at a relatively low temperature to produce ZnO nanofibers. Simultaneous thermal analyses were used to study the formation of ZnO nanofibers from the precursor material. X-ray diffraction was employed to analyze the phases and different microscopy techniques, such as scanning electron microscopy, transmission electron microscopy and atomic force microscopy were used to study the morphology and size of the fibers. Fourier transform infrared spectroscopy was employed to investigate the composition of the precursor and ZnO fibers. The specific surface area of the electrospun nanofibers was determined using the Brunauer–Emmett–Teller method and optical properties were measured by UV-Vis and PL spectroscopy. The very high specific surface area of the ZnO fibers makes them potential candidates for nanodevice applications in gas sensing, dye-sensitized solar cells, and UV/blue emission devices.

In this study, polyvinylidene fluoride (PVDF) membranes with various structures ranging from dense to highly asymmetric morphologies were obtained by changing the effective parameters in the phase inversion process. The effect of some important processing parameters such as solution concentration, harshness of the precipitation bath, exposure time before immersion in coagulation bath and bath temperature was studied and the mentioned parameters were optimized. The membranes were then modified with nano-sized alumina powder in order to improve the hydrophilicity of the PVDF membranes. The surface morphology, surface and cross-sectional structures of the membranes were examined by scanning electron microscope (SEM) and atomic force microscope (AFM). The specific surface area of the membranes was determined using the Brunauer–Emmett–Teller (BET) method. The contact angles between water and the membranes' surfaces were measured in order to study the hydrophilicity changes of the membrane surface. The results indicated that the addition of nano-sized alumina to the casting dope increased the hydrophilicity of the PVDF membrane surface.