High-quality WS2 film with the single domain size up to 400 μm was grown on Si/SiO2 wafer by atmospheric pressure chemical vapor deposition. The effects of some important fabrication parameters on the controlled growth of WS2 film have been investigated in detail, including the choice of precursors, tube pressure, growing temperature, holding time, the amount of sulfur powder, and gas flow rate. By optimizing the growth conditions at one atmospheric pressure, we obtained tungsten disulfide single domains with an average size over 100 μm. Raman spectra, atomic force microscopy, and transmission electron microscopy provided direct evidence that the WS2 film had an atomic layer thickness and a single-domain hexagonal structure with a high crystal quality. And the photoluminescence spectra indicated that the tungsten disulfide films showed an evident layer-number-dependent fluorescence efficiency, depending on their energy band structure. Our study provides an important experimental basis for large-area, controllable preparation of atom-thick tungsten disulfide thin film and can also expedite the development of scalable high-performance optoelectronic devices based on WS2 film.Electronic supplementary materialThe online version of this article (10.1186/s11671-017-2329-9) contains supplementary material, which is available to authorized users.

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In the present work, a ZnO nanowire array/reduced graphene oxide film hybrid nanostructure was realized, and the photovoltaic responses from the visible to the near-infrared range were investigated. Compared with the pure ZnO nanowire array and rGO thin film, the hybrid composite exhibited a fast and greatly enhanced broadband photovoltaic response that resulted from the formation of interfacial Schottky junctions between ZnO and rGO.

High energy density Li-ion hybrid flow capacitors are demonstrated by employing LiMn 2 O 4 and activated carbon slurry electrodes. Compared to the existing aqueous flow electrochemical capacitors, the hybrid one exhibits much higher energy densities due to the introduction of high capacity Li-insertion materials (e.g., LiMn 2 O 4 in the present work) as the flowable electrode with asymmetrical cell configuration. A record energy density, i.e., 23.4 W h kg −1 at a power of 50.0 W kg −1 has been achieved for aqueous flow capacitors tested at static condition reported to date. A full operational Li-ion flow capacitor tested in an intermittent-flow mode has also been demonstrated. The Li-ion hybrid flow capacitor shows great promise for high-rate grid applications.

A flexible NS@CNT composite is synthesized by electrodeposition, showing a record specific capacity in terms of the entire electrode mass.

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