A series of highly uniform one-dimensional Ni nanochains, with diameters ranging from 20 to 200 nm, have been synthesized by a facile, template-free, wet chemical method at diverse temperature and magnetic field. Our results indicate that the crystallite size, diameter and length of the prepared nanochains depend critically on the reaction temperature. The characteristic thermodynamic cohesive energies, ΔED and ΔEL, are obtained for the formation of the Ni nanochains. In addition, the chain length also depends on the applied field because of the Zeeman energy of the magnetic Ni nanoparticles. For the morphology control, an external field is required in order to obtain axially aligned rather than dendritic nanochains. The size-dependent magnetic properties are studied systematically. The saturation magnetization is shown to reduce inversely with the chain diameter, attributable to a core-shell structure. The thickness of the shell which encloses the ferromagnetic Ni core is determined to be about 2.3-3.4 nm.

In this paper, flower-, star-, and chain-like hierarchically nanostructured nickel crystals as well as [Ni(N2H4)2]Cl2 nanorods were first synthesized by a simple reduction method. This method is template-free, environmentally benign, and can be carried out at low temperature (60 °C) with high efficiency on a large scale. Investigation of the growth kinetics has proved that the crystal sizes are sensitive to the reaction temperature and reaction time. Various nickel nanostructures can be achieved by the oriented growth of preferred nickel crystal planes. The magnetic properties of the flower-like nickel nanocrystals were also characterized with the results of much enhanced coercivity (Hc) and decreased saturation magnetization (Ms).

ZnS nanomaterials at different dimensions, from nanoparticles, nanobelts to nanotetrapods have been synthesized in the same solvothermal system, which is kinetically controlled by ethylenediamine. Microscopy analysis reveals that the four arms of tetrapod are grownfromZn-terminated surfaces of an octahedral core by alternately stacking zinc blende and wurtzite structures along [111]/[0001] direction, while the ZnS nanobelts are selfassembled along [0001] direction by ultra-small wurtzite nanocrystals. These nanobelts can be transformed into their single-crystal counterparts and ZnO/ZnS heterostructures by thermal treatment. Uv–visible analysis demonstrates that the heterostructure presents a strain-induced staggered Type-II band structure. These investigation results suggest an efficient approach for phase-controlled synthesis of nanostructures in group II–VI semiconductors.

In this work, the solvent coordination molecular template effect of EN has been discussed in detail based on the microscopy analysis of the as synthesized ZnS nanostructures. As the EN concentration increases, the ZnS products evolve from symmetric NPs, 3D TPs to 1D NBs, accompanied with the microstructure transition from isotropic ZB to anisotropic WZ. The role of EN is significant in aspects of both the reaction rate control and the anisotropic growth activation due to the coordination effect between its amino groups and Zn atoms. Moreover, this modulation effect has been proved to be general for other short carbon-chain amine agents by the contrast experiments. The designed organic amine modulated solvothermal strategy could be utilized for controlled synthesis of other cubichexagonal combined II–VI nanostructures.

Synthesis and manipulation of advanced bimetallic nanomaterials via a green and low-cost wet chemical route are of great importance for the industrialization potential. Materials design integrating the synthesis of nanomaterials through an environmentally benign route with a simple manipulation method is a challenge. The CoPt hollow nanochains have been successfully synthesized in aqueous solution with shell thickness of about 5 nm and tunable length from 300 nm to 2 μm. The as-prepared CoPt hollow nanochains can be easily aligned by the external magnetic fields and can be attached onto substrates, such as silicon wafer. The synthesis strategy is characterized by room temperature reaction (300 K), low cost, and utilization of facile reagents (water as solvent). Growth kinetics investigation shows the magnetostatic interactions between Co clusters together with the spontaneous galvanic replacement between Co clusters and Pt ions are indispensable for the formation of aligned hollow nanochains. Magnetic measurements indicate that the shape anisotropy of 1D aligned nanochains plays a dominant role on the good controllable behavior.