Ink-jet printing is an important process for placing active electronics on plastic substrates. We demonstrate ink-jet printing as a viable method for large area fabrication of carbon nanotube ͑CNT͒ thin film transistors ͑TFTs͒. We investigate different routes for producing stable CNT solutions ͑"inks"͒. These consist of dispersion methods for CNT debundling and the use of different solvents, such as N-methyl-2-pyrrolidone. The resulting printable inks are dispensed by ink-jet onto electrode bearing silicon substrates. The source to drain electrode gap is bridged by percolating networks of CNTs. Despite the presence of metallic CNTs, our devices exhibit field effect behavior, with effective mobility of ϳ0.07 cm 2 / V s and ON/OFF current ratio of up to 100. This result demonstrates the feasibility of ink-jet printing of nanostructured materials for TFT manufacture.

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A light weight, economic, and high–energy density Zn/MnO 2 fiber battery was integrated with a textile body area network.

A model for carbon nanotube (CNT)/polymer composite conductivity is developed, considering the effect of inter-tube tunnelling through the polymer. The statistical effects of inter-tube distance and alignment on the tunnelling are investigated through numerical modelling, to highlight their role in the conductance and piezoresistance of the composite film. The impact of critical parameters, including the concentration, alignment and aspect ratio of the CNTs and the tunnelling barrier height of the polymer is statistically evaluated using a large number of randomly generated CNT/polymer composite films. A numerical model is presented for the tunnelling resistance as a function of CNT concentration and polymer properties, which provides good agreement with the reported conductance in the literature. In particular, for a low concentration of CNTs close to the percolation threshold, we demonstrate how tunnelling dominates the conductance properties and leads to significant increase in the piezoresistance of the composite. This is important for gaining insight into the optimum concentration and alignment of the CNTs in the composite film for applications such as strain sensors, anisotropic conductive films, transparent electrodes and flexible electronics.

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