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Nanocrystalline copper indium oxide (CuInO2) thin films with particle size ranging from 25 nm to 71 nm have been synthesized from a composite target using reactive Rf magnetron sputtering technique. X-ray photoelectron spectroscopy (XPS) combined with glancing angle X-ray diffraction (GAXRD) analysis confirmed the presence of delafossite CuInO2 phase in these films. The optical absorption studies show the presence of two direct band gaps at 3.3 and 4.3 eV, respectively. The resistance versus temperature measurements show thermally activated hopping with activation energy of 0.84 eV to be the conduction mechanism.

Tin oxide nanoparticle was successfully prepared by the chemical digestion method from the starting material as SnCl2. The SnO2 material was characterized by X-Ray Diffraction (XRD), Transmission Electron Microscope (TEM) and Selected Area Electron Diffraction (SAED). The SnO2 was an n-type material preferred to humidity sensing property towards the moisture. The response and recovery time of sensor was calculated as 129sec and 206sec respectively. It has exhibited better efficiency compared with the bulk SnO2 material. Additional Weight loss, EDS, FT-IR and resistivity measurements were also presented.

We report on the preparation of ferromagnetic cobalt nanospheres with antiferromagnetic oxide capping layer and its implication for the variation in magnetic property. The hcp cobalt nanospheres were prepared by thermal decomposition of cobalt carbonyl in the presence of organic surfactants. The spherical nanoparticles thus prepared were oxidized to grow antiferromagnetic layers of varying composition and thickness on top of cobalt spheres. High resolution transmission electron microscopy confirmed growth of Co 3 O 4 in one case and CoO in another case. Strong exchange anisotropy and enhanced coercive field was observed due to the core-shell structure in Co-CoO system. On the other hand only a marginal improvement was seen in Co-Co 3 O 4 system. A low temperature paramagnetic behavior was also observed that is interpreted in the framework of crystal defects in the oxide shell.