Vapor phase synthesis of supported Pd, Au, and unsupported bimetallic nanoparticle catalysts for CO oxidation

We report the vapor phase synthesis and characterization of supported Pd, Au and unsupported bimetallic nanoparticle catalysts for
CO oxidation. The approach utilized in the present work is based on the laser vaporization/controlled condensation technique which
uniquely combines the features of pulsed laser vaporization with the controlled condensation process from the vapor phase to synthesize
nanoparticle catalysts of controlled size and composition. The results indicate that supported Pd/CeO2, Au/CeO2, and unsupported
bimetallic CuPd, CuAu, and AuPd nanoparticle catalysts exhibit excellent activity for CO oxidation. The significance of the current
method lies mainly in its simplicity, flexibility and the control of the different factors that determine the activity of the nanoparticle
catalysts.
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Microwave Synthesis of Highly Aligned Ultra Narrow Semiconductor Rods and Wires

One dimensional nanostructures (rods, wires, tubes, ribbons) have recently attracted considerable attention. These nanostructures represent ideal systems for dimension dependent optical, electrical and mechanical properties, and are expected to play an important role as building blocks in devices and processes such as light-emitting diodes, solar cells, single electron transistors, lasers and biological labels.1,2 Many modern methods based on physical and chemical approaches have been developed for the synthesis of controlled size and shape of one dimensional nanostructures including, for example, vapor-liquid-solid and the solution-liquid-solid processes, solvothermal, template-assisted, kinetic growth control, self-assembly, and thermolysis of single-source precursor in ligating solvents.3 In addition to these methods, microwave irradiation (MWI) offers great advantges as the simplest and fastest procedure since selective dielectric heating, due to the difference in the solvent and reactant dielectric constants, can provide significant enhancement in reaction rates. Furthermore, MWI methods are unique in providing scaled-up processes without suffering thermal gradient effects, thus leading to a potentially industrially important advancement in the large-scale synthesis of nanomaterials. Although MWI methods have been demonstrated for the synthesis of a variety of high quality, nearly monodisperse semiconductor nanoparticles4, there are very few reports on the synthesis of one-dimensional semiconductors by MWI.3j-k,4 However, all the reported one-dimensional semiconductor nanostructures are wider than the Bohr radius, which limits the expected quantum confinement effects.
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A Room-Temperature and Microwave Synthesis of M-Doped ZnO (M = Co, Cr, Fe, Mn & Ni)

A room temperature and microwave method for the preparation M-Doped ZnO where M = Co, Cr, Fe, Mn & Ni is desribed. X-ray diffraction of the synthesized samples show a single phase ZnO structure without any indication of the dopant. Magnetic studies of the as prepared samples show it to be paramagnetic. However, hydrogenation of particular samples at 573 K for 6 hours resulted in transforming the samples to a room temperature ferromagnet.

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