Novel Fe2O3 hollow spheres with mesopores on the surface were first synthesized on a large scale by a facile and efficient hydrothermal process, without templates in the system. The samples were characterized by transmission electron microscopy (TEM), scanning electron microscopy (SEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and N2 adsorption−desorption. When the amorphous Fe2O3 hollow spheres were used as the photocatalytic material, they performed better than the nanocrystal samples. This synthetic procedure is straightforward and thus facilitates mass production of Fe2O3 hollow spheres.

Alpha-Ni(OH)(2) nanobelts, nanowires, short nanowires, and beta-Ni(OH)(2) nanoplates have been successfully prepared in high yields and purities by a convenient hydrothermal method under mild conditions from very simple systems composed only of NaOH, NiSO(4), and water. It has been found that the ratio of NaOH to NiSO(4) not only affects the morphology of the Ni(OH)(2) nanostructures, but also determines whether the product is of the alpha- or beta-crystal phase. A notable finding is that porous NiO nanobelts were produced after exposure of the Ni(OH)(2) products to an electron beam for several minutes during transmission electron microscopy (TEM) observations. Another unusual feature is that rectangular nanoplates with many gaps were obtained. Furthermore, porous NiO nanobelts, nanowires, and nanoplates could also be obtained by annealing the as-prepared Ni(OH)(2) products. A sequence of dissolution, recrystallization, and oriented attachment-assisted self-assembly of nanowires into nanobelts is proposed as a plausible mechanistic interpretation for the formation of the observed structures. The method presented here possesses several advantages, including high yields, high purities, low cost, and environmental benignity. It might feasibly be scaled-up for industrial mass production.

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Hollow Cu nano/microstructures are prepared by reduction of CuSO4 · 5 H2O with glucose by using a mild hydrothermal process. The X‐ray powder diffraction and energy‐dispersive X‐ray analysis indicate that the products are pure Cu and of cubic phase. The morphology of the products can be controlled between nanotubes and microspheres assembled from hollow nanoparticles by adjusting the concentration of sodium dodecyl sulfate. A series of experiments confirm that the concentration of the glucose and NaOH also play important roles in the formation of the hollow Cu nano/microstructures.

AgCl nanoparticles with a diameter of 50-100 nm were synthesized in ethylene glycol with the assistance of poly(vinylpyrrolidone) at room temperature. A photoactivation process was then introduced by exposing the as-obtained AgCl nanoparticle solution to common fluorescent lamp or direct sunlight irradiation to form a uniform layer of Ag nanoparticles (5-10 nm) on the surface of the AgCl nanoparticles. The AgCl/Ag nanocomposites showed higher visible light photo-[a] 3200 catalytic activity for decomposing organic pollutants [such as methyl orange (MO), methyl blue (MB), and rhodamine B (RhB)] under the irradiation of common fluorescent lamp or direct sunlight. Recycle photocatalysis experiments indicated that the AgCl/Ag nanocomposite exhibited higher stability. Moreover, the AgCl/Ag nanocomposites showed better antibacterial properties on Escherichia coli, Staphylococcus aureus, and Bacillus subtilis.

Well-aligned zinc oxide microrod and microtube arrays with high aspect ratios were fabricated on zinc foil by a simple solution-phase approach in an aqueous solution of ethylenediamine (en). The shape of the ZnO microstructures can be easily modulated from rods to tubes by adding cetyl trimethyl ammonium bromide (CTAB) into the reaction system. Control experiments demonstrate that some reaction parameters, such as the concentration of ethylenediamine, the kind of surfactant, reaction time, and the temperature, all have direct influences on the morphology of the products. Based on the early structure arising from arrested growth (nanosheets), a reasonable mechanism for the growth of ZnO microrods and microtubes has been proposed. The products were characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and photoluminescence emission.

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