Nanostructured electrical conductivity

The two approaches are not unrelated and a complementary analysis of both kinds of studies would finally shed light onto the detailed mechanisms for charge migration along DNA wires [51]. The kinetic theories are reviewed in other chapters of this book. Here, we focus on results obtained for the electronic structure of extended DNA base stacks, and describe their influence on the electrical conductivity of DNA-based nanostructures. 

The synthesis of nanostructured carbon using aliphatic alcohols as selfassembling molecules has demonstrated that this strategy can be extended beyond metal oxide-based materials [38]. Recently, we have reported the synthesis of a novel carbon material with tunable porosity by using a liquid-crystalline precursor containing a surfactant and a carbon-yielding chemical, furfuryl alcohol. The carbonization of the cured self-assembled carbon precursor produces a new carbon material with both controlled porosity and electrical conductivity. The unique combination of both features is advantageous for many relevant applications. For example, when tested as a supercapacitor electrode, specific capacitances over 120 F/g were obtained without the need to use binders, additives, or activation to increase surface area [38]. The proposed synthesis method is versatile and economically attractive, and allows for the precise control of the structure. 

Nanostructured Li and Ni containing nickel-metal hydride batteries are widely used in cell phones, video camcorders, quartz watches, and pacemakers to name a few uses. Electrically conducting nanostructured mesoporous materials are envisaged as new materials for fuel cell applications, batteries, and ultracapacitors. 

This scale effect indicates that the electrical conductivity is nearly constant for the films varying in thickness from 60 to 2,000 nm. The measured resistance, however, decreased when the film thickness further reduced. Both DC and AC conductivity measurements indicated that there was an enhanced conductivity for film thickness of <60 nm. They further proposed three orders of magnitude larger conductivity in 1.6-nm-thick films than lattice conductivity. Since the grain size was not provided, it is unknown whether only the grain size plays a role when a film s thickness is less than 60 nm. Guo et al. deposited YSZ thin films by pulsed laser deposition on MgO substrates with thicknesses of 12 and 25 nm. The electrical conductivity was measured in both dry and humid O2. The electrical conductivity in thin films, however, was found to be four times lower than ionic conductivity in microcrystalline specimens, as shown in figure 10.8. Furthermore, they found that there is not any remarkable proton conduction in the nanostructured films when annealed in water vapor. 

It is generally known that limits for speed-up of digital circuits, especially microprocessors, are determined by thermal problems. There are several analogues between the electrical Gp and the thermal Gp conductance of a nanostructure. However, an analysis of thermal conductance is more complex than electrical conductance because of contribution either phonons or electrons in heat exchange. Quantized thermal conductance in one-dimensional systems was predicted theoretically by Greiner [4] and Rego [5] for ballistic transport of electrons and phonons. Quantized thermal conductance Gp and its quantum (unit)... 

After asserting the nanostructured nature of ionic liquids, the structural analysis of these fluids continued in two different directions. The first was to check how the built-in flexibility of the isolated ions of the model affect (or are affected by) the nanostructured nature of the ionic liquid, and how that can influence properties like viscosity, electrical conductivity, or diffusion coefficients. It must be stressed that the charges in the CLAP model are fixed to the atomic positions, which means that the most obvious way to probe the relation between the structure of the ionic liquid as a whole in terms of the structure of its individual ions is to investigate the flexibility (conformational landscape) of the latter. The second alternative direction was to probe the structure of ionic liquids not by regarding into the structure of the component ions but by instead using an external probe (for example, a neutral molecular species), solubility experiments with selected solute molecules being the most obvious experimental approach. 

CORRELATION OF MORPHOLOGY AND ELECTRICAL CONDUCTION IN NANOSTRUCTURED PERYLENE PIGMENT FILMS... 

Electrically conductive polymers are perspective materials in modern technologies because of their potential applications as chemical sensors, catalysts, microelectronic devices, etc. [1]. The interest to new hybrid nanostructured materials based on polymer matrix with poly-7t-conjugated bonds and noble metals nanoparticles constantly increases. This is reasoned by a wide spectrum of new optical and electrophysical properties [2]. 

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