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Monodispersed lanthanum tartrate microspheres with flower-like shape were synthesized by a mild solvothermal method using ethanol-water mixed system as the solvent. Lanthanum oxide with reserved spherical shape was subsequently fabricated by a following calcination process. X-ray diffraction analyses (XRD), X-ray spectroscopy (EDS), scanning electron microscopy (SEM), thermogravimetry-differential thermal analysis (TG-DTA) were employed to characterize the composition, structure, and morphology of the products. The lanthanum tartrate microspheres were aggregated by nanosheets as petals. Size of the aggregation and thickness of the petal vary with the vol.% of ethanol. As the vol.% of ethanol increases the degree of aggregation and the thickness of the petal decrease, and other properties such as the size distribution, dispersion are also modulated. These alterations can be interpreted by the changing dielectric constant of mixed solvent. Such lanthanum tartrate can be applied to fabricate micro-sphereshaped lanthanum oxide after calcination.

In this paper, a template free method has been employed to fabricate porous ZnO. Brick shaped precursor was first synthesized by a mild hydrothermal process. Accompanied with the decomposition of the precursor during the subsequent annealing treatment, porous ZnO with the inherited morphology of the precursor was obtained. The as-prepared products were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). It exhibited that the porous hierarchical frame consists of nano-sheets with wurtzite-type. The size of the pores as well as the size of the particles varied with the annealing temperature. Mechanism speculation showed that the crystal-aggregation in the growth process of the precursor is the key to the establishment of pore structure.

Novel tomato-shaped copper oxide crystals has been prepared by a simple hydrothermal method with the presence of Zn 2+ ion. The ultrasonic pretreatment has proved to be the key factor during the synthesis process. Scanning electron microscope, energy dispersive X-ray spectrometry and powder X-ray diffraction were used to characterize the microstructure and morphology of the as-prepared products. The obtained tomato-shaped CuO particles were constructed by nanorods with the diameter of about 20 nm. The possible growth mechanism was proposed based on the experimental results.