Assembly of single layers: Three-dimensional assembly of single-layered MoS2 is achieved on a large scale via a solution method. The as-prepared tubular architectures have tunable size and mesopores in the shell, which are desirable for applications. As a example, they exhibit excellent lithium storage properties and are highly active for hydrodesulfurization of thiophene resulting from their structural advantages.

In this article, hierarchical flower-like ZnO nanostructures with controlled morphology and dimensions have been synthesized by solution phase approach and functionalized by Au nanoparticles (AuNPs) with the combination of electrodeposition to explore novel applications. The photocatalytic activity and lithium storage capacity of these hybrid nanostructures have been investigated. It has been found that hybrid nanostructure combining the large specific surface area, stability and catalytic activity of small AuNPs, demonstrate the higher photocatalytic activity than that of pure ZnO. Furthermore, an initial discharge capacity of 1280 mA h g À1 and a reversible capacity over 392 mA h g À1 at the 50 cycles are achieved for the Au-ZnO hybrid nanostructure, which is found to be much better than that of any previously reported ZnO anodes. The improved lithium storage capacity and cycle life of the Au-ZnO electrode result from the Li activity of Au-ZnO phase. The photocatalytic and electrochemical activity of Au-ZnO hybrid nanostructures provide a new platform for energy storage, environmental remediation and photocatalysis applications.

Nitrogen-enriched porous carbon nanofiber networks (NPCNFs) were successfully prepared by using lowcost melamine and polyacrylonitrile as precursors via electrospinning followed by carbonization and NH 3 treatments. The NPCNFs exhibited inter-connected nanofibrous morphology with a large specific surface area, well-developed microporous structure, relatively high-level nitrogen doping and great amount of pyridinic nitrogen. As free-standing new anode materials in lithium-ion batteries (LIBs), the NPCNFs showed ultrahigh capacity, good cycle performance and superior rate capability with a reversible capacity of as high as 1323 mA h g À1 at a current density of 50 mA g À1 . These attractive characteristics make the NPCNFs materials very promising anode candidates for high-performance LIBs and, as free-standing electrode materials to be used in other energy conversion and storage devices.

Through a facile hydrothermal method with a special surfactant triethanolamine (TEA) followed by thermal treatment, monodispersed micro-/nanostructured Co3O4 powders with unique morphology (cube) have been synthesized successfully as anode material for Li-ion batteries (LIBs). The regular Co3O4 microcubes (∼2.37 μm in the average side length) consist of many irregular nanoparticles (20-200 nm in diameter, 30-40 nm in thickness) bonded to each other, which greatly inherit the morphology and size of the precursor CoCO3. The specific surface area of Co3O4 powders is about 5.10 m(2)·g(-1) by the Brunauer-Emmett-Teller (BET) method, and the average pore size is about 3.08 nm by the Barrett-Joyner-Halenda (BJH) method. In addition, the precursor is verified as a single-crystal, while the mesoporous cubic Co3O4 is a polycrystalline characteristic assembled by numerous single-crystal nanoparticles. More remarkable, the high performance of the micro-/nanostructured cubic Co3O4 powders has been obtained by the electrochemical measurements including high initial discharge capacities (1298 mAhg(-1) at 0.1 C and 1041 mAhg(-1) at 1 C), impressive rate capability, and excellent capacity retention (99.3%, 97.5%, 99.2%, and 89.9% of the first charge capacities after 60 cycles at 0.1 C, 0.2 C, 0.5 C, and 1 C, respectively).

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Instantaneous electrical breakdown measurements of GaN and Ag nanowires are performed by an in situ transmission electron microscopy method. Our results directly reveal the mechanism that typical thermally heated semiconductor nanowires break at the midpoint, while metallic nanowires breakdown near the two ends due to the stress induced by electromigration. The different breakdown mechanisms for the nanowires are caused by the different thermal and electrical properties of the materials.

Three-dimensionally ordered macro/mesoporous Ce 0.6 Zr 0.3 Y 0.1 O 2 (3DOM CZY) supported high-dispersion Pt nanoparticles (x wt % Pt/3DOM CZY, x = 0.6, 1.1, and 1.7) were successfully synthesized via the cetyltrimethylammonium bromide/triblock copolymer P123 assisted gas bubbling reduction route. The 3DOM CZY and x wt % Pt/3DOM CZY samples exhibited a high surface area of 84−94 m 2 /g. Pt nanoparticles (NPs) with a size of 2.6−4.2 nm were uniformly dispersed on the surface of 3DOM CZY. The 1.1 wt % Pt/3DOM CZY sample showed excellent catalytic performance, giving a T 90% value at 598 °C at gas hourly space velocity (GHSV) of 30000 mL/(g h) and the highest turnover frequency (TOF Pt ) of 6.98 × 10 −3 mol/(mol Pt s) at 400 °C for methane combustion. The apparent activation energy (64 kJ/mol) over 1.1 wt % Pt/3DOM CZY was much lower than that (95 kJ/mol) over Bulk CZY. The effects of water vapor and SO 2 on the catalytic activity of 1.1 wt % Pt/3DOM CZY were also examined. It is concluded that the excellent catalytic activity of 1.1 wt % Pt/3DOM CZY was associated with its high oxygen adspecies concentration, good lowtemperature reducibility, and strong interaction between Pt NPs and CZY as well as large surface area and unique nanovoidwalled 3DOM structure.

Although carbonaceous materials possess long cycle stability and high power density, their low-energy density greatly limits their applications. On the contrary, metal oxides are promising pseudocapacitive electrode materials for supercapacitors due to their high-energy density. Nevertheless, poor electrical conductivity of metal oxides constitutes a primary challenge that significantly limits their energy storage capacity. Here, an advanced integrated electrode for high-performance pseudocapacitors has been designed by growing N-doped-carbon-tubes/Au-nanoparticles-doped-MnO2 (NCTs/ANPDM) nanocomposite on carbon fabric. The excellent electrical conductivity and well-ordered tunnels of NCTs together with Au nanoparticles of the electrode cause low internal resistance, good ionic contact, and thus enhance redox reactions for high specific capacitance of pure MnO2 in aqueous electrolyte, even at high scan rates. A prototype solid-state thin-film symmetric supercapacitor (SSC) device based on NCTs/ANPDM exhibits large energy density (51 Wh/kg) and superior cycling performance (93% after 5000 cycles). In addition, the asymmetric supercapacitor (ASC) device assembled from NCTs/ANPDM and Fe2O3 nanorods demonstrates ultrafast charge/discharge (10 V/s), which is among the best reported for solid-state thin-film supercapacitors with both electrodes made of metal oxide electroactive materials. Moreover, its superior charge/discharge behavior is comparable to electrical double layer type supercapacitors. The ASC device also shows superior cycling performance (97% after 5000 cycles). The NCTs/ANPDM nanomaterial demonstrates great potential as a power source for energy storage devices.