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The preliminary characterization of thin-film transistors (TFTs) based on a dispersion of ZnO nanorods in an n-type polymer semiconductor, [6, 6]-phenyl-[C.sub.61]-butyric acid methyl ester (PCBM), is reported. The results obtained showed a highly promising enhancement for high-performance solution-processable n-type OTFTs.

The synthesis and applications of semiconducting nanostructures such as zinc oxide (ZnO) nanowires and tungsten disulfide (W[S.sub.2]) nanotubes is reported. The findings from the studies could be used to fabricate the transistors/phototransistors and photovoltaic (PV) energy conversion cells.

Linear wave energy converters generate intrinsically intermittent power with variable frequency and amplitude. A composite energy storage system consisting of batteries and super capacitors has been developed and controlled by buck-boost converters. The purpose of the composite energy storage system is to handle the fluctuations and intermittent characteristics of the renewable source, and hence provide a steady output power. Linear wave energy converters working in conjunction with a system composed of various energy storage devices, is considered as a microsystem, which can function in a stand-alone or a grid connected mode. Simulation results have shown that by applying a boost H-bridge and a composite energy storage system more power could be extracted from linear wave energy converters. Simulation results have shown that the super capacitors charge and discharge often to handle the frequent power fluctuations, and the batteries charge and discharge slowly for handling the intermittent power of wave energy converters. Hardware systems have been constructed to control the linear wave energy converter and the composite energy storage system. The performance of the composite energy storage system has been verified in experiments by using electronics-based wave energy emulators. [ABSTRACT FROM AUTHOR]

The possibility of enhancing the frequency performance of electrochemical capacitors by tailoring the nanostructure of the carbon electrode to increase electrolyte permeability is demonstrated. Highly porous, vertically oriented carbon electrodes which are in direct electrical contact with themetallic current collector are produced viaMPECVD growth onmetal foils.Theresulting structure has a capacitance and frequency performance between that of an electrolytic capacitor and an electrochemical capacitor. Fully packaged devices are produced on Ni and Cu current collectors and performance compared to state-of-the-art electrochemical capacitors and electrolytic capacitors.The extension of capacitive behavior to the AC regime (~100Hz) opens up an avenue for a number of new applications where physical volume of the capacitor may be significantly reduced. [ABSTRACT FROM AUTHOR]

Herein we present an inexpensive facile wet-chemistry-free approach to the transfer of chemical vapour-deposited multiwalled carbon nanotubes to flexible transparent polymer substrates in a single-step process. By controlling the nanotube length, we demonstrate accurate control over the electrical conductivity and optical transparency of the transferred thin films. Uniaxial strains of up to 140% induced only minor reductions in sample conductivity, opening up a number of applications in stretchable electronics. Nanotube alignment offers enhanced functionality for applications such as polarisation selective electrodes and flexible supercapacitor substrates. A capacitance of 17 F/g was determined for supercapacitors fabricated fromthe reported dry-transferred MWCNTs with the corresponding cyclic voltagrams showing a clear dependence on nanotube length [ABSTRACT FROM AUTHOR]

In this paper, we report on the synthesis and applications of semiconducting nanostructures. Nanostructures of interest were zinc oxide (ZnO) nanowires and tungsten disulfide (WS2) nanotubes where transistors/phototransistors and photo-voltaic (PV) energy conversion cells have been fabricated. ZnO nanowires were grown with both high- and low-temperature approaches, depending on the application. Individual ZnO nanowire side-gated transistors revealed excellent performance with a field- effect mobility of 928 cm² /V · s. ZnO networks were proposed for large-area macroelectronic devices as a less lithographically intense alternative to individual nanowire transistors where mobility values in excess of 20 cm² /V · s have been achieved. Flexible PV devices utilizing ZnO nanowires as electron acceptors and for photoinduced charge separation and transport have been presented. Phototransistors were fabricated using individual WS2 nanotubes, where clear sensitivity to visible light has been observed. The results presented here simply reveal the potential use of inorganic nanowires/tubes for various optoelectronic devices. [ABSTRACT FROM AUTHOR]

We demonstrate a rechargeable zinc-ion battery with high energy density and cyclability using MnO2 and reduced graphene oxide (MnO2/rGO) electrode. The flexible and binder free electrode, with high MnO2 mass ratio (80 wt% of MnO2), is fabricated using vacuum filtration without any additional additives other than rGO. Compared to batteries with conventional MnO2 electrodes, the Zn–MnO2/rGO battery shows a significant enhanced capacity (332.2 mAh g-1 at 0.3 A g-1), improved rate capability (172.3 mAh g-1 at 6 A g-1) and cyclability. The capacity retention remains 96% after 500 charge/discharge cycles at 6 A g-1. The high MnO2 mass ratio makes MnO2/rGO electrode advantageous when the capacity is normalized to the whole electrode, particularly at high rates. The calculated gravimetric energy density of Zn–MnO2/rGO battery is 33.17 W h kg-1, which is comparable to the existing commercial lead-acid batteries (30–40 W h kg-1). Furthermore, the discharge profile and capacity of our Zn–MnO2/rGO battery shows no deterioration during bending test, indicating good flexibility. As a result, zinc-ion battery is believed to be a promising technology for powering next generation flexible electronics. Zinc-ion batteries: a carbon based promoter Simple carbon materials are shown to modify the MnO2 electrodes and greatly enhance the capacity and cyclability for zinc-ion batteries. An international team led by Prof Hang Zhou from Peking University Shenzhen Graduate School, China developed high performance flexible zinc-ion batteries with MnO2 and reduced graphene-oxide composites as the electrodes. The electrodes are prepared by vacuum filtering the suspension of the mixture of reduced graphene oxide and hydrothermal synthesized MnO2 nanosheets. The incorporation of reduced graphene oxide not only enhances the battery capacity by improving the conductivity and increasing the specific surface area, but also reduces the production cost by saving the trouble to use other binders or additives. Due to above advantages, this approach is competitive for wearable energy storage devices. [ABSTRACT FROM AUTHOR]

The article presents a correction to the paper "Zinc Oxide Nanostructures and High Electron Mobility Nanocomposite Thin Film Transistors," by Flora M. Li, Gen-Wen Hsieh, Sharvari Dalal, et al., from the November 2008 issue.