Urchinlike TiO2 spheres with tunable chamber structure were synthesized using a template-free solvothermal method. The unique sphere-in-sphere chamber structure allows multiple reflections of UV light resulting in greatly enhanced photocatalytic activity. This work provided novel structural platforms for novel materials and device applications.

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Cu nanowires hold great promise for the fabrication of low-cost transparent electrodes. However, their current synthesis is mainly performed in aqueous media with poor nanowire dispersibility. We report herein the novel synthesis of ultralong single-crystalline Cu nanowires with excellent dispersibility, providing an excellent candidate material for high-performance transparent electrode fabrication.

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The tunnelling of electrons through molecules (and through any nanoscale insulating and dielectric material ) shows exponential attenuation with increasing length , a length dependence that is reflected in the ability of the electrons to carry an electrical current. It was recently demonstrated that coherent tunnelling through a molecular junction can also be suppressed by destructive quantum interference , a mechanism that is not length-dependent. For the carbon-based molecules studied previously, cancelling all transmission channels would involve the suppression of contributions to the current from both the π-orbital and σ-orbital systems. Previous reports of destructive interference have demonstrated a decrease in transmission only through the π-channel. Here we report a saturated silicon-based molecule with a functionalized bicyclo[2.2.2]octasilane moiety that exhibits destructive quantum interference in its σ-system. Although molecular silicon typically forms conducting wires , we use a combination of conductance measurements and ab initio calculations to show that destructive σ-interference, achieved here by locking the silicon-silicon bonds into eclipsed conformations within a bicyclic molecular framework, can yield extremely insulating molecules less than a nanometre in length. Our molecules also exhibit an unusually high thermopower (0.97 millivolts per kelvin), which is a further experimental signature of the suppression of all tunnelling paths by destructive interference: calculations indicate that the central bicyclo[2.2.2]octasilane unit is rendered less conductive than the empty space it occupies. The molecular design presented here provides a proof-of-concept for a quantum-interference-based approach to single-molecule insulators.

Nanocomposites of interpenetrating carbon nanotubes and vanadium pentoxide (V2O5) nanowires networks are synthesized via a simple in situ hydrothermal process. These fibrous nanocomposites are hierarchically porous with high surface area and good electric conductivity, which makes them excellent material candidates for supercapacitors with high energy density and power density. Nanocomposites with a capacitance up to 440 and 200 F g−1 are achieved at current densities of 0.25 and 10 A g−1, respectively. Asymmetric devices based on these nanocomposites and aqueous electrolyte exhibit an excellent charge/discharge capability, and high energy densities of 16 W h kg−1 at a power density of 75 W kg−1 and 5.5 W h kg−1 at a high power density of 3 750 W kg−1. This performance is a significant improvement over current electrochemical capacitors and is highly competetive with Ni–MH batteries. This work provides a new platform for high‐density electrical‐energy storage for electric vehicles and other applications.

Bi 2 O 3 /TiO 2 nanocrystallines with ordered mesoporous structure are synthesized by ab evaporation-induced self-assembly method. During liquid-phase photocatalytic degradation of p-chlorophenol under visible illumination (λ > 420 nm), this catalyst exhibits high activity owing to the synergetic effects of both the Bi 2 O 3 -photosensitization and the unique structural characteristics. The Bi 2 O 3 -photosensitization of TiO 2 could extend the spectral response from UV to visible area, making the Bi 2 O 3 /TiO 2 photocatalyst easily activated by visible lights. The ordered mesoporous channels facilitate the diffusion of reactant molecules. Meanwhile, the high surface area could enhance the Bi 2 O 3 dispersion, the light harvesting, and the reactant adsorption. Furthermore, the highly crystallized anatase may promote the transfer of photoelectrons from bulk to surface and thus inhibit their recombination with photoholes, leading to enhanced quantum efficiency.

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