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Uniform ZnO nanospheres have been successfully synthesized through a facile solvothermal process. The structure and morphology of the products were characterized by powder X-ray diffraction, scanning electron microscopy, and transmission electron microscopy. The results showed that the products were ZnO nanospheres of 300–350 nm in diameter, which were composed of nanoparticles of ca. 5–10 nm. The size of the nanospheres can be tuned from ca. 300 nm to 1 μm by changing the concentration of the reactants. The gas sensing performance of the ZnO nanospheres with different size were investigated, which indicated that the ZnO nanospheres exhibited good gas sensitivity and selectivity towards n-butanol. In addition, the gas sensitivity of the ZnO nanospheres exhibited obvious size-dependent effect.

Cu 2 O/amorphous TiO 2 core–shell nanocomposites with uniform cubic structure were prepared by a hydrolysis method and CuO/TiO 2 core–shell nanocomposites were obtained by a post-calcination process. The structure and morphology of the products were characterized by powder X-ray diffraction, transmission electron microscopy, and scanning electron microscopy. The results showed that the cubic Cu 2 O/TiO 2 core–shell nanocomposites were of 110–140 nm in side length and the as-hydrolyzed TiO 2 shell layer was amorphous. The products transformed to quasi-spheric CuO/TiO 2 (anatase) nanocomposites after calcination. The visible-light photocatalytic properties of different products towards methyl orange (MO) were investigated. The results showed that the photocatalytic activity of the cubic Cu 2 O/amorphous TiO 2 core–shell nanocomposites was higher than that of pure Cu 2 O nanocubes, pure TiO 2 nanoparticles, and the spheric CuO/TiO 2 core–shell nanocomposites.

Uniform Cu2O nanoparticles have been successfully synthesized through a facile additive-free aqueous solution route at room temperature. The structure and morphology of the products were characterized by powder X-ray diffraction, transmission electron microscopy, and scanning electron microscopy. The results showed that the products were Cu2O nanocubes of 110–130 nm in side length. The size of the nanocubes can be tuned from 20 nm to 500 nm by changing the concentration of the sodium hydroxide solution and the kind of copper salts. The visible-light photocatalytic properties of the as-obtained Cu2O products were investigated. The results showed that these Cu2O nanoparticles exhibited good photocatalytic activity towards methyl orange (MO).

Uniform hematite nanoparticles have been successfully synthesized through a surfactant mediated hydrothermal method. The structure and morphology of the products were characterized by powder X-ray diffraction, transmission electron microscope, scanning electron microscope, and Fourier transform infrared spectrometer. The results showed that the products were α-Fe2O3 nanoellipsoids of 115–140 nm in long axis and 60–80 nm in short axis. The growth mechanism of the products was proposed based on the experiments. Uniform nanospindles, nanoellipsoids, nanospheres, and nanopolyhedra with different sizes can be obtained by adjusting the reaction temperature, the amount of additive, and concentration of the reactants. The result may facilitate the exploration of controlled synthesis of α-Fe2O3 nanoparticles.

Single-crystal cuprous iodide semiconductor nanospheres were fabricated via a mild low-temperature solution route by using polyvinyl pyrrolidone as capping agent and the mixture of water and polyethylene glycol 400 as solvent. The structure, morphology, and properties of the products were characterized by powder X-ray diffraction, transmission electron microscopy, scanning electron microscopy, thermal gravimetry and photoluminescence spectrometry. The results showed that the products were CuI nanospheres of ca. 280–650 nm in diameter and were composed of quasi-trigonal particles of ca. 20–40 nm. The phase transformation temperature and the melting point of the products decreased by ca. 12 and 8 °C compared with the bulk CuI. The possible formation mechanism was discussed on the basis of experimental results.

High quality ceramics in Zn(Ta 1− x Sb x ) 2 O 6 (0.05≤ x ≤0.20) compounds were synthesized by the conventional solid-state reaction method. The effects of Sb 5+ ion substitution on microstructures, phase composition and microwave dielectric properties were investigated. A phase change or crossover from ZnTa 2 O 6 to ZnSb 2 O 6 occurred at x =0.1. Well-developed microstructures of ceramics can be achieved at 1250 °C and the distribution of grain size was optimized due to the existence of ZnSb 2 O 6 phase. With Sb 5+ ion substitution, the quality factors Qf values were enhanced effectively and ranged from 72,400 to 119,600 GHz owing to the meliorative grain size distribution. The dielectric constant and the temperature coefficient of resonant frequency ( τ f ) were strongly dependent upon the Sb 5+ ion concentration and the presence of the second phase of ZnSb 2 O 6 .

Nearly monodisperse Co 3 O 4 nanospheres were fabricated via a facile polyethylene glycol 400-mediated solventhermal route followed by a calcination process at 500 °C. The structure, morphology, and properties of the products were characterized by powder X-ray diffraction, scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectrometry, and UV–vis spectrometry. The results showed that the products were Co 3 O 4 nanospheres of 160–170 nm in diameter and were composed of nanoparticles of ca. 40 nm. The possible formation mechanism was discussed on the basis of experimental results. Furthermore, optical property of the products was characterized.