In this work, a facile route using a simple solvothermal reaction and sequential calcinations to synthesize porous R-Fe 2 O 3 flower-like nanostructures without employing templates or matrices for self-assembly is presented. The flower-like nanostructures are composed of nanosheets with a thickness of about 20 nm, which are characterized by field-emission scanning electron microscopy (FESEM). Influencing factors such as the dosage of reactants and the solvents are systematically investigated. A possible formation mechanism for the flower-like nanostructure is proposed. A BET test shows that the product is porous and has a large surface area. The electrochemical, magnetic, and photocatalytic properties of the as-obtained R-Fe 2 O 3 3D nanostructure are systematically investigated. The result shows that these properties are greatly affected by the porous structure.

A micromachined absorbance and fluorescence detection cell for application to capillary electrophoresis within planar glass substrates (chips) is described. A microfabricated U-cell for absorbance provides a longitudinal path 120-140 µm long parallel to the flow direction and gives at least a 10-fold increase in absorbance compared to an absorbance path transverse to the flow direction. Absorbance detection limits of 0.003 AU gave ∼6 µM detection limits for hydrolyzed fluorescein isothiocyanate dye. The same device can be used for longitudinal fluorescence excitation with a 20-fold improvement in signal-tobackground levels due to reduced scattering, utilizing a form of sheath flow. Fluorescence detection limits of ∼20 000 molecules and 3 nM were obtained for fluorescein.

Powders of single-crystalline β-nickel hydroxide (β-Ni(OH) 2 ) nanosheets with the hexagonal structure have been successfully synthesized by the hydrothermal method at 200 °C using nickel acetate as the nickel source and aqueous ammonia as both an alkaline and complexing reagent. The yields of β-Ni(OH) 2 nanosheet powders were higher than 92.4%. This method is simple and low-cost for large-scale production of powders of singlecrystalline β-Ni(OH) 2 nanosheets. Single-crystalline nickel oxide (NiO) nanosheets have been synthesized by thermal decomposition method at 400 °C for 2 h using single-crystalline β-Ni(OH) 2 nanosheets as the precursor. The sheet shape of β-Ni(OH) 2 was sustained after thermal decomposition to NiO. The as-prepared products were characterized by X-ray powder diffraction (XRD), transmission electron microscopy (TEM), differential scanning calorimetric analysis (DSC), and thermogravimetric analysis (TG).

In this article, a facile route using simple hydrothermal reaction and sequential calcinations to synthesize α-Fe2O3 hollow nanostructures without employing templates or matrices is presented. By simply changing the basic source, hollow spindles and microspheres can be selectively synthesized. The concentration of the reagents and the kind of basic source or coordination reagents are verified to have great influence on the morphologies of the products. TEM images clearly show the hollow natures of the as-obtained products. Growth mechanisms for the hollow nanostructures were proposed. Because of the unique hollow structures of the samples, the potential applications of the as-obtained hematite hollow nanostructures on lithium ion battery and water treatment were also investigated.