Uniform Cu 2 O nanocubes with various sizes were synthesized by reducing Cu(OH) 2 using ascorbic acid in the presence of various amounts of sodium citrate. The monodispersed nanocubes with an edge length of approximately 80 nm used as an anode exhibit excellent lithium storage behavior.

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This work reports on a simple hydrothermal method for tuning the shape and exposed face of TiO 2 nanocrystal by using sodium titanate as a precursor in the presence of different alkali metal ion salts. The {101}-exposed anatase TiO 2 was synthesized in lithium salt solution. The formation of anatase TiO 2 with exposed high-index {301} facet, obtained in the presence of sodium ions, has never before been reported upon. When the reaction proceeded in potassium salt solution, the obtained anatase TiO 2 with a high aspect ratio was elongated in the ,001. direction. Anatase TiO 2 with a high aspect ratio was obtained in hydrothermal process in the presence of low charge density high atomic number alkali metal ions, which were not easily absorbed by the {001} planes of anatase, so the growth along this direction was not restrained. The photodegradation of methylene blue, assisted by anatase TiO 2 with various exposed faces reveals that the photoactivity of anatase {101} planes is larger than that of {301} planes.

We reveal the thickness effects on optical properties for nanoparticles in the shape of hollow spheres theoretically and experimentally. Within and beyond the electrically small limit, hollow spheres are shown to have almost the same light absorption power as that of solid ones, when the ratio of inner core to whole particle radii is smaller than 0.4. It means that one can maintain the level of light absorption even with a large empty core. In the electrically small limit, we expand the exact solution of Mie theory in power of the thickness parameter and show that the thickness ratio has less influence on light absorption. Moreover, we synthesize highly uniform hollow spheres of TiO2 anatase through a self-sacrificing template method. A variety of particle radii from 94 to 500 nm, with 50 nm in the shell thickness, are performed experimentally in photocatalytic activity. With experimental demonstrations and theoretical simulations, our results provide a guideline in the design on the thickness for hollow-sphere nanoparticles with an optimized absorption power in light harvesting.

In this work, brookite TiO 2 has been synthesized by a simple hydrothermal approach using sodium titanate as a precursor in the presence of a sodium fluoride aqueous solution. The ratio of brookite and anatase TiO 2 can be tailored by the NaF concentration. In a concentrated NaF solution, high quality brookite TiO 2 was acquired. Pure anatase nanoparticles were obtained in only deionized water.Moreover, the morphology and size of brookite TiO 2 can be tailored by using various acid treated titanates which influence the stability of the building blocks and nucleation points of TiO 2 . Micro-sized flower-like brookite, submicro-sized urchin-like brookite and brookite nanorods with anatase nanoparticles were obtained. The micro-sized flower-like brookite remains the same shape and phase even at 800°C, whereas obvious grains were formed on the matrix with brookite, rutile and anatase mixture phases at 900°C. On the other hand, as the submicro-sized urchin-like brookite was heated, a rutile phase appeared at 750°C and 100% grain-like rutile was obtained at 900°C.