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Electrospinning is a convenient and versatile method for fabricating different kinds of one-dimensional nanostructures such as nanofibres, nanotubes and nanobelts. Environmental parameters have a great influence on the electrospinning nanostructure. Here we report a new method to fabricate hafnium oxide (HfO(2)) nanobelts. HfO(2) nanobelts were prepared by electrospinning a sol-gel solution with the implementation of heating and subsequent calcination treatment. We investigate the temperature dependence of the products by scanning electron microscopy (SEM), transmission electron microscopy (TEM), selected area electron diffraction (SAED), and energy-dispersive x-ray (EDX) spectroscopy. The heating temperature of spinning ambient is found to be crucial to the formation of HfO(2) nanobelts. By tuning the temperature, the morphological transformation of HfO(2) from nanowires to nanobelts was achieved. It was found that the rapid evaporation of solvent played an important role in the formation process of HfO(2) nanobelts. It is shown that nanobelts can only be obtained with the temperature higher than 50 °C and they are in the high quality monoclinic phase. A possible growth mechanism of the nanobelts based on phase separation is proposed. The enhanced photoluminescence (PL) of HfO(2):Eu(3+) nanobelts is also illustrated.

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We report herein a simple method for attaching vinyl groups onto the sidewalls of carbon nanotubes (CNTs) and the application of vinyl-carbon nanotubes (CNT-C¼ ¼C) in fabricating polymer composites. The synthesis of CNT-C¼ ¼C was monitored with IR spectroscopy, Raman spectroscopy, and thermogravimetric analysis. The obtained CNT-C¼ ¼C showed good compatibility with the in situ polymerization of poly(methyl methacrylate) (PMMA) and exhibited no tendency for phase separation in the final composite. A transmission electron microscopy study revealed a uniform coating on the CNT-C¼ ¼C tubes, indicating good grafting efficiency of PMMA. The uniform dielectric PMMA coating was responsible for the lower electrical conductivity of the CNT-C¼ ¼C/PMMA composites versus that of the CNTs without vinyl modification.

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