It is shown that the dominant conduction mechanism in single‐wall carbon nanotube networks at room temperature is variable range hopping. Thin networks follow a variable range hopping law throughout the temperature range 4 K < T < 300 K, thick networks display variable range hopping characteristics in the range 50 K < T < 300 K, with deviation to Bloch–Grüneisen behaviour at lower temperatures. The adsorption state of these materials is shown to determine the sign of change in conductance upon subsequent exposure to oxygen. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

The electrical conductance of single- and double-wall carbon nanotube systems was measured by a mechanically controllable break-junction technique using freestanding nanotubes not subject to any chemical modification. For metallic single-wall carbon nanotubes, two channels with transmission coefficient of 0.88 contribute to ballistic electronic transport at room temperature. In double-wall carbon nanotubes, one metallic channel contributes to ballistic electronic transport and additional field- and temperature-dependent two-channel contributions were observed.

a b s t r a c tIn this work we introduce equations describing the morphological dependency of electron transport in nano-structured solar cells. Using the hopping model for electron transport and using the trap contained diffusion model we define an expression to explain the dependency of the electron diffusion coefficient and conductance versus porosity and surface roughness. Validity of the obtained theoretical formula is examined by a random walk simulation based on hopping model in a fully disordered medium with a random distribution of energy. A Monte-Carlo random walk simulation was used to investigate the effects of morphology on the electron transport in the porous nano-structures. For generation of the random packing of nanoparticles, a stochastic cluster model was utilized. The porosity and surface roughness of the generated porous media were tuned by changing the particle size and the overlap parameters.

The ordered ferromagnetic–antiferromagnetic [Formula: see text] alloy nanowires were fabricated successfully by alternating current (AC) electrodeposition into nanoporous anodized aluminum oxide (AAO). The NiMn alloy nanowires were deposited in a simple sulfate bath. Effect of bath composition on Mn content of electrodeposited nanowires as well as the thermal annealing effect on magnetic properties were explored. The magnetic properties of NiMn alloy nanowires were enhanced significantly, compared to corresponding bulk materials. Magnetic parameters, such as coercivity and saturation magnetization were decreased with increasing the Mn content. For thermal annealing process, it was found that these parameters were enhanced with increasing the temperature up to 300[Formula: see text]C, on the other hand, they were decreased with increasing the temperature to 500[Formula: see text]C. Moreover, the X-ray diffraction (XRD) patterns revealed that the FCC crystalline structure of Ni turns to an amorphous phase by increasing the Mn content in the nanowires, resulting in a significant reduction in the [Formula: see text].

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