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Copper nanowires have been synthesized at different pH values through the template assisted electrodeposition technique using polycarbonate track-etch membranes as scaffolds. The effect of pH (0.8-2.8) of the electrolyte on structure, morphology, composition and deposition rate of copper into the pores of the template, while keeping other electrochemical conditions same, was investigated. X-ray diffraction analysis confirmed the face centered cubic phase of synthesized nanowires. With the change in pH, no shift in peaks was observed except the inclusion of an additional peak of copper oxide in nanowires synthesized at pH 2.8. The nanocrystallite size, strain, lattice stress and energy density were evaluated by X-ray analysis. Field emission scanning electron microscopy images revealed that nanowires obtained at pH 0.8, 1.1 and 1.4 showed incomplete deposition in the pores of the membrane whereas, the nanowires obtained at pH 1.7 were densely stacked, vertically aligned and uniform along the diameter and that obtained from pH 2.0-2.8 had overdeposition on their top. An increase in deposition rate was observed with the increase in pH value. The average diameter of Cu nanowires was found to be ~ 105 nm. The electrical conductivity of as-grown nanowires was observed to decrease 13-fold as the transition from bulk values to the nanosystem. Nanowires prepared at pH of 1.7 were characterized for their field-emission properties. A very large field-enhancement factor of ~ 10,855 was obtained indicating that Cu nanowires grown by reported technique shows outstanding potential as efficient field-emitters for flat panel displays. [ABSTRACT FROM AUTHOR]

The electrical properties of electrodeposited zinc-copper-telluride (ZnCuTe) nanowires embedded in polycarbonate track-etch membrane (Whatman) having pore-diameters of 200, 100 and 50nm have been studied and reported in this paper. Scanning electron microscopy (SEM) confirmed the formation of the nanowires of uniform diameter equal to the diameter of the templates used. I-V measurements at room temperature (303K) reveal that the nanowires of diameter 200, 100 and 50nm have linear and ohmic characteristics. Higher electron transport was observed in larger diameter nanowires compared to smaller ones which may be attributing to size effect. The temperature-dependent electrical transport measurements over a temperature range 308- 423K reveal that the temperature dependence of electrical conductivity increases with increasing temperature and decreases as the nanowires size decreases. The study reveals that ZnCuTe nanowires have negative temperature coefficient of resistance (TCR). [ABSTRACT FROM AUTHOR]

In this paper, large scale synthesis of Ag2S nanowires having diameter 100 nm using chemical reaction is reported. Nanochannels in anodic alumina membrane were utilized as templates. Scanning electron microscopy was used for morphological study of nanowires. X-ray diffraction depicted the monoclinic nature of Ag2S nanowires. Energy dispersive X-ray fluorescence recommended that the nanowires are of pure silver sulfide rather than any silver compound. Nonlinear I-V characteristics were observed for Ag/Ag2S/Ag heterostructures. [ABSTRACT FROM AUTHOR]

In this paper, electrochemical fabrication and characterization of CdS nanowires having diameter 100 and 200 nm is reported. Nano-channels in anodic alumina membrane were utilized as template. Morphological study of nanowires was made using Scanning electron microscopy (SEM). UV-visible absorption and laser induced time resolved photoluminescence (PL) spectroscopy were used for optical characterization. UV-visible absorption depicts that, there is slight increase in band gap of nanowires with decrease in diameter of nanowires. PL measurements indicate emission band peak of 435 and 420 nm in case of 200 and 100 nm wires respectively. These studies are very important regarding the synthesis and optoelectronic applications of CdS nanowires. [ABSTRACT FROM AUTHOR]

The paper presents the synthesis of ZnO nanowires (~100 nm) from aqueous solution at relatively lower temperature (~70 °C) by cathodic electrodeposition using anodic alumina membrane (AAM). The nanowires were characterized by scanning electron microscopy, X-ray diffraction and photoluminescence. Strong reflections corresponding to (100), (002), (101), (102) and (110) indicate the Wurtzite structure of synthesized ZnO nanowires. Room temperature time resolved photoluminescence study shows the visible emission at 590 nm (2.1 eV) which is attributed to deep level emission on account of defects. Time resolved photoluminescence studies are very important, if we want to use these ZnO nanowires for any optoelectronic application. [ABSTRACT FROM AUTHOR]

The electrochemical template synthesis of high aspect-ratio nickel nanorods in the track-etch membranes of polycarbonate having nominal pore size of 80, 50 and 30 nm is considered. The morphological and structural analyses have been carried out through scanning electron microscopy and X-ray diffraction respectively. The synthesized nanorods possess FCC lattice structure with texturing for {220} planes. When excited with UV radiation pulse, the structures exhibited weak photoluminescence with exponential decay, which is attributed to the presence of some adsorbed metal hydroxide. [ABSTRACT FROM AUTHOR]

Polypyrrole nanocylinders were produced by non-galvanically (chemically) synthesizing polypyrrole within the pores of nanoporous polycarbonate ion track-etched membranes. The morphology of the nanowires was characterized by scanning electron microscopy. The electrical conductivity of the nanocylinders was calculated by leaving the nanocylinders fixed in the insulating template membrane and evaluating the transmembrane resistance. [ABSTRACT FROM AUTHOR]

Discusses scanning electron microscopy (SEM) morphology and X-ray diffraction (XRD) characterization of nickel microstructure arrays synthesized by dc electrodeposition in porous polycarbonate templates. Nickel sulphate solution containing boric acid; Cylindrical pores of uniform diameter; Solid state nuclear track detectors.

In this paper, we report the preparation of nanowalled hollow tubules of Ag2Se in to the pores of track-etch membrane (TEMs). Using the electrolyte solution (0.01 M AgNO3 and 0.3 M SeO2 + 0.03 M H2SO4 + 50% DMSO), a current density 0.06 A cm-2 was applied for 20 minutes. The tubules were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD) and energy dispersive X-ray (EDX) techniques. The SEM photographs show the high aspect ratio of the tubules and EDX analysis shows good stiochiometric composition of the Ag2Se product. [ABSTRACT FROM AUTHOR]