The strategy to manipulate nanoscale building blocks into well-regulated hierarchical architectures is of great interest and valuable to both material synthesis and advanced nanodevices. Novel ZnO hierarchical structures with nanowire arrays connected on both faces of parallel ZnO hexagonal disks were produced in a facile temperature-dependent multi-step hydrothermal route within an open vessel, in which lamellar zinc hydroxide (LHS-Zn) disks were firstly formed as intermediate basic floor, whose surface may be roughened at elevated temperature; the resultant ZnO nanowires were then assembled into a highly ordered array on the top/bottom surfaces of disks in the presence of dense ammonia. Higher [Zn 2+ ] at the beginning lead to multicell sandwiches or nanowire-disk-nanowire-disk-nanowire-like superlattice. Ammonia molecules in the vessel play a key role in controlling architecture evolution. Room-temperature Raman-scattering and photoluminescence measurements indicated the optical properties of single as-prepared ZnO structure.

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Poly(acrylic acid) (PAA) coated-Fe3O4 superparamagnetic nano-composites were synthesized through a solvothermal technique by using cheap and environmental friendly iron salts and PAA. Each nano-composite was composed of many small primary nanocrystals. The as-synthesized products were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), high resolution transmission electron microscopy (HRTEM), vibrating sample magnetometer (VSM), Fourier transform infrared spectroscopy (FTIR), thermogravimetric-differential scanning calorimetry (TG-DSC) analysis and nitrogen adsorption-desorption measurements. These nano-composites showed rapid adsorption rate and super removal capacity of cation organic dye methylene blue (MB). Moreover, the MB desorption could be easily performed using methanol and acetic acid mixed solution. The reused performance of the nano-composites was also studied.

The synthesis of TiO(2) nanostructures including nanowires and nanobelts has been demonstrated experimentally by anodization of Ti foil in an electrolyte, and by treatment in a PdCl(2) ethanol solution together with UV light irradiation and annealing at a temperature below 800 degrees C. The TiO(2) nanotube arrays resulting from the anodization were used as source precursor and transformed into nanowires and nanobelts respectively with high efficiency during the subsequent processes. The resulting TiO(2) nanowires and nanobelts, characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), and Raman and surface photovoltage (SPV) spectroscopy, are single rutile crystals of high quality. In addition to the synthesis of the nanostructure at low temperature, this method also shows great advantages for the selectable morphology of the final TiO(2) nanostructures via adjustment of the UV light irradiation time and annealing temperature.

Composite structures of aligned and orientation-ordered quasi-one-dimensional CdS micro/nanostructures on CdSe substrates of different shaped nanostructures have been synthesized by using two-step thermal evaporation processes. The CdSe substrate crystalline orientations and local temperatures play their roles in the CdS nanostructure growth step, which is in some contrast with the vapor-liquid-solid (VLS) growth mechanism. Micro-photoluminescence measurements show strong luminescence responses on the six-fold symmetrical CdSe/CdS nanostructure. Controllable growth on various shaped substrates may find applications in obtaining many other aligned orientation-ordered hetero-nano/microstructure materials.