Monodisperse Fe3O4 nanocubes have been successfully synthesized by a facile solvothermal method at 260 °C in the presence of oleic acid and oleylamine. Well-defined assembly of uniform Fe3O4 nanocubes with an average size of 12 nm could be obtained without a size-selection process. The shape of as-prepared Fe3O4 nanoparticles could be reversibly interchanged between spheres and cubes by adjusting the reaction parameters. The phase structures, morphologies, and sizes of as-prepared products were investigated in detail by X-ray diffraction (XRD), transmission electron microscopy (TEM), and high-resolution transmission electron microscopy (HRTEM). The magnetic properties of Fe3O4 nanocubes were measured by using a quantum design superconducting quantum interference device (SQUID). The magnetic study reveals that the as-synthesized nanocubes are ferromagnetic at 2 K while they are superparamagnetic at 300 K.

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Uniform single-crystalline indium hydroxide microcubes can be successfully synthesized in large quantities via a convenient hydrothermal route using hydrated indium nitrate and sodium borohydride as reagents under mild conditions. The morphology and size of indium hydroxide microcubes can be controlled by varying the synthetic parameters such as hydrothermal time, reaction temperature, and surfactant. Single-crystalline indium oxide microcubes also can be successfully prepared by a thermal decomposition method using indium hydroxide microcubes as the precursor. The phase structures, morphologies, and optical properties of the final products were investigated in detail by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, differential scanning calorimetric analysis, thermogravimetric analysis, and photoluminescence spectroscopy. These uniform single-crystalline microcubes may be useful in microelectronic and optoelectronic devices.

Single-crystalline - nanocubes were successfully obtained in large quantities through a facile one-step hydrothermal synthetic route under mild conditions. In this synthetic system, aqueous iron (III) nitrate () served as iron source and triethylamine served as precipitant and alkaline agent. By prolonging reaction time from 1 h to 24 h, the evolution process of -, from nanorhombohedra to nanohexahedron, and finally nanocube, was observed. The products were characterized by Powder X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), High-resolution Transmission Electron Microscopy (HRTEM), Selected-Area Electron Diffraction (SAED), and Fourier Transform Infrared Spectrometry (FTIR). The possible formation mechanism was discussed on basis of the experimental results.

Single-crystalline yttrium hydroxide nanotubes could be successfully synthesized in large quantities via a metastable nanosheet precursor reacted with sodium hydroxide under hydrothermal conditions. The nanosheet precursors were obtained through a facile hydrothermal synthetic method using soluble yttrium nitrate as the yttrium source and triethylamine as both an alkaline and complexing reagent. The influences of reaction time and concentration of sodium hydroxide on the formation of yttrium hydroxide nanotubes were investigated. Yttrium oxide and europium-doped yttrium oxide nanosheets and nanotubes could also be selectively obtained via a thermal decomposition method using the corresponding hydroxides as precursor. The phase structures, morphologies, and properties of the as-prepared products were investigated in detail by X-ray powder diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), selected area electron diffraction (SAED), high-resolution transmission electron microscopy (HRTEM), and photoluminescence spectroscopies. The formation mechanisms of yttrium hydroxide nanotubes were discussed based on the experimental results. These low-dimensional nanostructures could be expected to bring new opportunities in the vast research and application areas.