We present a detailed study on the growth process of cupric oxide (CuO) nanowires by thermal oxidation. The morphology of nanowires, obtained at different oxidation temperatures and times, was determined. The diameter of nanowires was found to depend linear on temperature whereas the time dependence of their length is modeled by a parabolic law. The results suggest that CuO nanowires are formed as a result of the competition between grain boundary and lattice diffusion of Cu atoms across a Cu2O layer. Electrical characterization of the nanowires was also performed. A field effect transistor was produced with an isolated nanowire showing p-type characteristics. The resistivity, mobility, and density of carriers were calculated. Nanowire growth by thermal oxidation is very simple and has great potential to be used for large scale production; this opens possibilities for various kinds of application.

The reactivity of the redox-active tetracarboxylic acid derived from the tetrathiafulvalene (TTF-TC)H(4) with alkaline cations (K, Rb, Cs) is reported. The exploration of various experimental parameters (temperature, pH) led to the formation of four crystalline three-dimensional coordination polymers formulated M(2)(TTF-TC)H(2) (M = K, Rb, Cs), denoted MIL-132(K), MIL-133(isostructural K, Rb), and MIL-134(Cs). Thermogravimetric analysis and thermodiffraction show that all of the solids are thermally stable up to 150-200 degrees C in the air. In order to exploit the possibility of oxidation of the organic linker in TTF-based compounds, they were employed as positive electrodes in a classical lithium cell. A highly reversible cyclability was achieved at high current density (10 C) with a reasonable performance (approximately 50 mAh g(-1)). Finally, combined electro-(sub)hydrothermal synthesis was used to prepare a fifth 3-D coordination polymer formulated K(TTF-TC)H(2) (denoted MIL-135(K)), this time not based on the neutral TTF-TC linker but its radical, oxidized form TTF-TC(+*). This solid is less thermally stable than its neutral counterparts but exhibits a semiconducting behavior, with a conductivity at room temperature of about 1 mS cm(-1).

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