The nested carbon nanotubes discovered by Ijima and co-workers as a by-product of fullerene production extended the dimension and geometries of fullerenes into the domain of nanoparticles. These nanotubes are fiberlike structures consisting of concentric graphite sheets nested along the axis extending as long as several micrometers, and diameters of these nanotubes are limited to less than 100 nm. In this paper we report preparation, structural and magnetic properties of cobalt-doped carbon nanotubes. We observed a tubular structure made of coaxial graphite sheets. The inside, of these carbon nanotubes, was filled with cobalt particles. The magnetic properties of the Co-doped nanotubes were measured using a SQUID magnetometer. The undoped (pure) carbon nanotubes exhibit diamagnetic behavior. The Co-doped nanotubes exhibit superparamagnetic behavior with saturation of magnetization at about 0.5 T and coercive field of 750 G.

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In this paper had been studied the characterization of the nanocatalyst (NiO) Mesh electrodes. For fuel cell. The catalyst is prepared and also the electrodes The structural were studied through the analysis of X-ray diffraction of the prepared nanocatalyst for determining the yielding phase and atomic force microscope to identify the roughness of prepared catalyst surface, Use has been nanocatalyst led to optimization of cell voltage, current densities & power for a fuel cell.

Study of the development of an activated carbon nanotube catalyst for alkaline fuel cell technology. Through the prepared carbon nanotubes catalyst by an electrochemical deposition technique. Different analytical approaches such as X-ray diffraction (XRD) to determine the structural properties and Scanning Electron Microscope (SEM), were used to characterize, Mesh stainless steel catalyst substrate had an envelope structure and a large surface area. Voltages were also obtained at 1.83 V and current at 3.2 A of alkaline fuel cell. In addition, study the characterization of the electrochemical parameters.

In this research SnO 2 thin films have been prepared by using hot plate atmospheric pressure chemical vapor deposition (HPCVD) on glass and Si (n-type) substrates at various temperatures. Optical properties have been measured by UV-VIS spectrophotometer, maximum transmittance about (94%) at 400 0 C. Structure properties have been studied by using X-ray diffraction (XRD) , its shows that all films have a crystalline structure in nature and by increasing growth temperature from(350-500) 0 C diffraction peaks becomes sharper and grain size has been change. Atomic force microscopy (AFM) uses to analyze the morphology of the Tine Oxides surface structure. Roughness & Root mean square for different temperature have been investigated. The results show that both increase with substrate temperature increase this measurements deal with X-Ray diffraction results, that there is large change in the structure state of SnO2 thin f film by changing temperature parameter.