Large-scale self-assembly of meso-, micro-, and nanostructured building components with highly specific morphology and novel properties are of great interest to chemists and material scientists. Remarkable progress has been made in the self-assembly of highly organized building blocks of metals, [1] semiconductors, [2] copolymers, [3] organic-inorganic hybrid materials, [4] and biomaterials [5] based on different driving mechanisms. However, controlling the assembly of primary building units, for example flakes, into curved hollow structures is still a challenge for materials self-assembly.[6] The ability to assemble primary units into hollow structures is in great demand by scientists not only because of the role this plays in better understanding the concept of self-assembly with artificial building blocks but also for its great potential for technological applications. [7] Vanadium oxides, in which the vanadium is known to exist in a wide range of oxidation states, from +2, as in VO, to +5, as in V 2 O 5 , have been extensively studied as a well-known kind of transition-metal oxide because they have unique electrical and optical properties. [8] Regarding the V 5+ and V 4+ oxides, various nanostructures (e.g., nanotubes, nanowires, nanofibers, nanobelts, nanorods, and mesoporous structures) have already been synthesized by a variety of methods, [9] including reverse-micelle transition, the sol-gel process, hydrothermal treatment, and electrochemical deposition. As expected, the various nanostructures of V 4+and V 5+ oxides lead to a wide variety of potential applications, including sensors, [10] optical switching devices, [11] optical datastorage media, [12] and electrode materials for Li secondary batteries.[13] By contrast, there are only limited reports concerning the synthesis of V 3+ oxide nanostructures and their interesting properties, [14] and thus it still remains a challenge to develop simpler and versatile approaches to V 3+ oxide nanostructures.In this communication, we describe a simple hydrothermal method to organize as-formed building blocks of flakes into VOOH hollow curved architectures by means of the "aggregation-then-growth" process: 1) freshly formed VOOH monomers aggregate around the gas/liquid interface to form hollow VOOH spheres and 2) the in situ formed building units of flakes continue to grow during the following hydrothermal process. This one-pot hierarchical organizing scheme relies primarily on the N 2 gas bubbles produced in the reaction process, representing another way of organizing flake building blocks into hollow curved architectures; this is different from previously reported ways using, for example, emulsified soft templates, hydrophobic attraction, or the solid templates resulting from variation of the chemical composition of the building units.[15] The as-obtained VOOH hollow "dandelions", a new-phased and unique V 3+ oxide nanostructure, offer the first opportunity to investigate the Li + charge-and-discharge electrochemical properties for V 3+ oxides.Important info...

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Necklace-like hollow carbon nanospheres (CNSs) have been successfully synthesized from the pentagon-including reactants, which provide an auxiliary example for the theoretical prediction that necklace-like hollow CNSs are assumed to be composed of the regular occurrence of nonhexagonal rings at the atomic level. Benefits of the as-obtained hollow CNSs also arise from the high Brunauer-Emmett-Teller value of 594.32 m(2)/g and a narrow pore distribution at 5 nm. The electrochemical hydrogen storage experiments for the as-obtained necklace-like hollow CNSs exhibit a capacity of 242 mAh/g at the current density of 200 mA/g, corresponding to a hydrogen storage of 0.89 wt %, which is higher than the previously reported electrochemical capacities for the multiwalled carbon nanotubes (MWCNTs). Furthermore, the as-obtained necklace-like hollow CNSs show a lithium capacity advantage compared with the carbon solid particles for application in lithium batteries. These results indicate that the necklace-like hollow CNSs provide a new candidate for the application in hydrogen storage and lithium batteries.

In this paper, we present an effective synthetic protocol to produce high quality InN nanocrystals using indium iodide (InI 3 ), one member of the family of indium halides, as the indium source at a low temperature of o250 1C (far below the decomposition temperature of InN). Notably, reports on InN synthesized from indium halides are rare due to the lack of well-defined synthetic protocols. Here, indium iodide (InI 3 ), with a stronger covalent ability, can also prevent the In 31 from being reduced to elemental indium, and then InN is formed. This synthetic protocol not only provides an alternative method to successfully synthesize highquality InN, but is also useful to fabricate other functional materials by using stronger covalent reactants to prevent reduction/oxidation in the oxidation/reduction reaction process, respectively. Furthermore, we also report the first example of an orientation-attachment process occurring between the metal nitride particles. The high purity of the InN nanoparticles can be seen from the XPS and HRTEM results, showing the asobtained products possess no obvious iodine or amorphous layers on the surface of particles, respectively. By controlling the parameters of reaction temperature and time, nanoparticles with different sizes were obtained as the final products. Raman and IR results indicate that our experimental data were consistent with the theoretical prediction and this gives further evidence that high quality InN nanocrystals were obtained. Moreover, it has been shown that the near-infrared band around 0.7 eV is characteristic of these samples and there were no obvious peaks around 1.9 eV, indicating that these InN nanocrystals exhibit a band gap of 0.7 eV, rather than the previously accepted 1.9 eV.