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In this paper, we present experimental results describing enhanced readout of the vibratory response of a doubly clamped zinc oxide (ZnO) nanowire employing a purely electrical actuation and detection scheme. The measured response suggests that the piezoelectric and semiconducting properties of ZnO effectively enhance the motional current for electromechanical transduction. For a doubly clamped ZnO nanowire resonator with radius ∼10 nm and length ∼1.91 µm, a resonant frequency around 21.4 MHz is observed with a quality factor (Q) of ∼358 in vacuum. A comparison with the Q obtained in air (∼242) shows that these nano-scale devices may be operated in fluid as viscous damping is less significant at these length scales. Additionally, the suspended nanowire bridges show field effect transistor (FET) characteristics when the underlying silicon substrate is used as a gate electrode or using a lithographically patterned in-plane gate electrode. Moreover, the Young's modulus of ZnO nanowires is extracted from a static bending test performed on a nanowire cantilever using an AFM and the value is compared to that obtained from resonant frequency measurements of electrically addressed clamped-clamped beam nanowire resonators. [ABSTRACT FROM AUTHOR]

This paper presents a flexible, integrated piezoelectric system that is simultaneously designed to operate as a self-powered touch sensor and as a charge pump and storage device for the long-term accumulation of energy over several pressure cycles. Rectification is achieved by stacking a piezoresistive polymer on top of a piezoelectric polymer, so that the conductivity of the former switches in phase with the generation of charge in the latter, upon application and release of stress. A thin flexible electrochemical capacitor is then stacked onto the structure to store the generated charge. The resulting integrated generator proves a robust device of general applicability, featuring a flexible and deformable nature, a large dynamic range, and simple manufacturing. [ABSTRACT FROM AUTHOR]

As a result of their morphology, nanowires bring new properties and the promise of performance for a range of electronic devices. This review looks into the properties of nanowires and the multiple ways in which they have been exploited for energy generation, from photovoltaics to piezoelectric generators. [ABSTRACT FROM AUTHOR]