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Determination of the helicity of carbon nanotubes (CNTs) is useful for CNTs in nanoelectronic device applications. Using electron diffraction to measure chiral angle with a high precision is reviewed, and helix-shaped carbon nanostructures are introduced and characterized by transmission electron microscopy. The possible formation mechanism of helix-shaped CNTs is also referred in the paper.

High yields of multi-walled carbon nanotubes are synthesized by chemical vapor deposition of acetylene on palladium nanoparticles supported on porous SiO2. HRTEM results reveal that the carbon nanotubes have novel conical inner structure. By changing the content of palladium in the catalyst, we obtained palladium nanoparticles with different diameter distribution. It was found that the apex angles of cones, the outer diameter and the length have a dependence on the diameter of the palladium nanoparticles. Due to the presence of open graphite layers, these novel carbon nanotubes have fascinating potential for energy storage, filed emission and composites.

Spindle-type α-Fe2O3 Nanoparticles have been synthesized via a hydrothermal method, using Fe(NO3)3, NH4Cl and ethylene glycol as starting precursors. The resultant products were characterized by means of Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), transmission electron microscopy (TEM), high resolution transmission electron microscopy (HRTEM) and vibrating sample magnetometer (VSM). The results indicate that the synthesized individual spindle-type α-Fe2O3 nanoparticles are single crystals, and their hysteresis loops show that they have two kinds of magnetic properties, diamagnetism and paramagnetism.

Magnetite (Fe3O4) nanoparticles uniformly loaded on multi-walled carbon nanotubes (MWCNTs) were synthesized by a wet chemistry method, and then carbon coated Fe3C nanoparticles supported by MWCNTs were prepared by heat-treatments subsequently in nitrogen at 600 degC and in acetylene atmosphere at 500 degC. The as-prepared nanoparticles were all single crystals with a size distribution ranging from 10 to 60nm upon TEM and XRD measurements. The magnetic properties of these two kinds of nanoparticles were measured using vibrating sample magnetometer (VSM) at room temperature. The results show that above materials are useful for magnetic materials, and the method to produce magnetic nanoparticles coated with graphite is rather simple

Nano-sized ZnO crystals with catalytic, electrical, optoelectronic, and photochemical properties have been considered as an important candidate in both fundamental research and practical studies. However, controllable synthesis of ZnO in morphology and size with a simple method under mild conditions still represents a challenge. We proved that ZnO nanostructures, including particles and nanorods, could be fabricated by a solvothermal route. Precursors of Zn(Ac)2 and LiOH reacted in ethanol at temperatures lower than 150degC. Then zinc oxide nanocrystals with a hexagonal wurtzite structure were formed. These ZnO nanocrystals were single crystalline, as confirmed by high-resolution transmission electron microscopy. The size of ZnO nanoparticles was determined by reaction temperature. Prolong reaction time, ZnO nanorods were formed and they grew along the [001] direction, whose aspect ratio was also changed with reaction time