With sodium hydroxide (NaOH), ammonia water (NH3 x H2O) and hexamethylenetetramine (HMT, C6H12N4) respectively as alkaline source material, a simple hydrothermal process was employed to prepare chrysanthemum-like ZnO nanowire clusters. The morphologies and crystalline structures of the as-prepared products were investigated by X-ray diffractometer (XRD), field emission environment scanning electron microscope (SEM), and high-resolution transmission electron microscopy (TEM). The experimental results indicate that the as-prepared products all have three-dimensional chrysanthemum-like structure in which the petal-like nanowires are ZnO single crystalline with hexagonal wurtzite structure, that the flower bud saturation degree F(d) is slightly different under different alkaline source materials, and that the proposed growth mechanism of chrysanthemum-like ZnO nanowire clusters is reasonable.

The flower-like SnO2 particles are synthesized through a simple hydrothermal process. The microstructure, morphology and the infrared emissivity property of the as-prepared products are characterized by x-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscope (TEM), and infrared spectroradio meter (ISM) respectively. The results show that the as-prepared SnO2 products are all indexed to tetragonal cassiterite phase of SnO2. The different molarity ratios of the OH− concentration to Sn4+ concentration ([OH−]:[Sn4+]) and the polyacrylamide (PAM) lead to the different morphological structures of SnO2, which indicates that both the [OH−]:[Sn4+] and the PAM play an important role in the morphological evolution respectively. The infrared emissivities of the as-prepared SnO2 products are discussed.