Hierarchical and well-defined cobalt sulfide with flower-like, cube-like, ball-like, and surface hollowed-out nanostructures were successfully prepared by a facile one-pot hydrothermal synthesis approach, employing Co(NO(3))(2)·6H(2)O as a cobalt precursor and thiourea as a sulfur source. The morphologies of these structures can be easily controlled by simply adjusting the molar ratio of reactants and solvents, reaction time, reaction temperature, and ligand types. Thiourea plays two important roles in the growth process of CoS nanostructures. First, it is decomposed to produce S(2-) for the final formation of CoS. On the other hand, it serves as a structure-directing agent to control the crystalline growth of CoS. The electrochemical capacitance performances of the CoS nanostructures were studied, and the flower-like CoS nanostructures show the best charge-discharge performance among all CoS products with the highest specific capacitance values of 389 F g(-1) at current density of 5 mA cm(-2), and 277 F g(-1) at higher current density of 50 mA cm(-2).

Well-defined perovskite MTiO 3 (M = Ba, Sr, Ca and Mg) nanostructures were successfully synthesized by a convenient hydrothermal method, employing MCl 2 as M source and titanate nanowire as Ti precursor. Different perovskite nanostructures such as nanoring, nanobowl, nanotube, and nanodisk were successfully prepared. Two types of growth mechanisms were proposed by investigating the formation processes of MTiO 3 nanostructures. The formation of MTiO 3 (M = Ba and Sr) undergoes a "nanowire-tube-ring" growth mechanism with a self-sacrifice of titanate nanowire framework rout, whereas the formation of CaTiO 3 and MgTiO 3 structures follows a simultaneous epitaxial growth of TiO 2 nanotube on titanate nanowire and self-nucleation of MTiO 3 (M = Mg and Ca) in the solution initially, and then a conversion of the nanowire and nanotube to MgTiO 3 /CaTiO 3 nanostructure process. The electrical properties of the perovskite MTiO 3 nanostructure including polarization-field hysteresis and capacitance-voltage characteristics were also investigated.

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Nanofibers of natural cotton cellulose with a degree of polymerization above 10,000 were prepared by electrospinning; they were then functionalized with a rare‐earth nano‐oxide material of cerium dioxide (CeO2) by means of the hydrothermal method to obtain the designated properties. The morphology, structure, and properties of the as‐obtained nanocomposite fibers were characterized by scanning electron microscopy, transmission electron microscopy, energy‐dispersive spectroscopy, X‐ray diffraction, Fourier transform infrared spectroscopy, and ultraviolet (UV)–visible spectrophotometry. The results show that hydrothermally grown CeO2 nanoparticles exhibited a polycrystalline cubic fluorite structure and could be dispersed uniformly on the surface of the cellulose nanofiber. The strong interface and electrostatic interactions between the nanoparticles and nanofibers effectively prevented nanoparticle fall‐off. The modified natural cotton cellulose nanofibers showed excellent protection against UV radiation because of the function of the CeO2 particles. Such cellulose nanocomposite materials could have potential applications in UV protection for data‐storage or memory devices. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 1524–1529, 2013

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