Titanium oxide filled polyvinylpyrrolidone (PVP) composite nanofibers have been prepared via a simple electrospinning technique. The combination of good TiO 2 properties with its high surface area leads these nanofibers into having a vast applicability such as cosmetics, scaffolds for tissue engineering, catalytic devices, sensors, solar cells, and optoelectronic devices. The structural and chemical properties of the prepared samples have been studied. The presence of the TiO 2 phase on the nanofibers was confirmed. An anatase to rutile transformation was observed at 600 ∘ C. Regarding the thermogravimetric and differential thermal analysis (TGA/DTA), the TIP decomposition and the PVP evaporation at 225 ∘ C were verified.

Hysteresis loops showing the decrease of the saturation magnetic moment (left) through a dense array of vertically-aligned Ni nanotubes after their progressive thermal conversion into hybrid ferromagnetic/antiferromagnetic Ni/NiO nanotubes (right).

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We report the synthesis, structural and ferroelectric characterization of continuous well-aligned nanofibres of barium titanate produced by the electrospinning technique. The fibres with average diameter of 150-400 nm consist of connected nanoparticles of BaTiO 3 stacked together to form the shape of a long filament. The tetragonal phase in the obtained nanofibres was revealed by the x-ray diffraction and Raman spectroscopy and has been also confirmed by the second harmonic generation (SHG) and piezoresponse force microscopy (PFM). The temperature dependence of the SHG in the vicinity of the paraelectric-ferroelectric phase transition suggests that barium titanate nanofibres are indeed ferroelectric with an apparent glass-like state caused by metastable polar nanoregions. The existence of domain structure and local switching studied by PFM present clear evidence of the polar phase at room temperature.