@article { ISI:000237477400077, title = {Directed organization of gold nanoclusters on silver nanowires: a step forward in heterostructure assembly}, journal = {Applied Physics Letters}, volume = {88}, number = {19}, year = {2006}, month = {MAY}, pages = {193103}, publisher = {AMER INST PHYSICS}, type = {Article}, address = {CIRCULATION \& FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA}, abstract = {

We investigate the directed assembly of tridecylamine protected gold nanoclusters of 4-5 nm size on functionalized silver nanowires of 55-60 nm diameter and the electron transfer behavior of this integrated structure using transmission electron microscopy, non-contact atomic force microscopy, and scanning tunneling microscopy/spectroscopy. Linear I-V for bare silver nanowire suggests metallic behavior but high tunnel resistance indicates presence of insulating layer on the surface. Identical I-Vs obtained for isolated gold nanoparticle and heterostructure suggests that electron transport across nanowires in the latter is governed by gold nanoparticles in contrast to expected ballistic or diffusive transport along their length.(c) 2006 American Institute of Physics.

}, issn = {0003-6951}, doi = {10.1063/1.2200284}, author = {Sharma, J. and Vivek, J. P. and Vijayamohanan, K. P. and Singh, P. and Dharmadhikari, C. V.} } @article { ISI:000242601000036, title = {Electron transfer behavior of monolayer protected nanoclusters and nanowires of silver and gold}, journal = {Journal of Nanoscience and Nanotechnology}, volume = {6}, number = {11}, year = {2006}, note = {International Conference on Nanoscience and Nanotechnology, Gwangju Inst Sci \& Technol, Gwangju, SOUTH KOREA, NOV 10-12, 2005}, month = {NOV}, pages = {3464-3469}, publisher = {Gwangju Jeonnam Nano Technol Union}, type = {Article}, address = {25650 NORTH LEWIS WAY, STEVENSON RANCH, CA 91381-1439 USA}, abstract = {

Understanding the electron transfer behavior of nanometer sized, both metallic and semiconducting particles and wires is important due to the fundamental interest in size and shape dependent electronic properties and also because of its applications in nano-electronic devices like single electron transistors and molecular switches. Monolayer protected nanoclusters enable one simple and elegant method of synthesis of these types of metallic and semiconducting materials using interfacial chemistry as has been successfully used in several applications ranging from catalysis to molecular electronics. The success of this type of nanostructured materials is due in part to the well known protecting/stabilizing action of the ligands (also known as surface passivating/capping agents), which facilitate the synthesis and processing of these hydrophobic colloids in solution form. The present article discusses the electron transfer behavior of silver nanowires and nanoparticles with varied sizes. In particular, we have investigated the electrochemical properties of silver nanowires (diameter 70 nm, length several micrometers) and compared with the behavior of similar relatively larger sized nanoparticles (size 40 nm). A critical analysis of the redox behavior of silver nanowires and nanoparticles is presented in aqueous medium under various electrolytic conditions along with a comparison of analogous properties of smaller sized (2-7 nm) silver and gold nanoclusters.

}, keywords = {cyclic voltammetry, nanoclusters/nanoparticles, Nanowires}, issn = {1533-4880}, doi = {10.1166/jnn.2006.035}, author = {Sharma, Jadab and Vivek, J. P. and Vijayamohanan, Kunjukrishna P.} } @article { ISI:000286307300007, title = {Synthesis of Sb-doped SnO2 nanowires and hyperbranched structures}, journal = {Science of Advanced Materials}, volume = {1}, number = {1}, year = {2009}, month = {APR}, pages = {38-43}, publisher = {AMER SCIENTIFIC PUBLISHERS}, address = {26650 THE OLD RD, STE 208, VALENCIA, CA 91381-0751 USA}, abstract = {

Branched nanostructures of semiconducting materials are of great interest for their potential applications in optoelectronic, photonic devices and sensors. We herein describe a facile single-step chemical vapor deposition route for the synthesis of Sb-SnO2 hyperbranched nanostructures comprised of elongated nanowires with 30-40 nm diameter and 10-20 Am length. The morphology and structure has been characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), selective area electron diffraction (SAED), and powder X-ray diffraction (XRD). Also, a possible mechanism is proposed for the growth of nanowires into the hyperbranched form on the basis of the substrate effect, the role of Au nanoparticles, and the effect of Sb doping on specific morphology evolution. Interestingly, electrical conductivity measurements as a function of temperature suggest a semiconducting behavior, despite being governed by different electron-transport mechanisms with activation energies of 0.55 and 0.17 eV, which correspond to pure SnO2 and Sb-SnO2 nanowires, respectively. A precise control over the operating parameters not only envisages custom-designed, branched structures by a simple and economical route but also offers an alternative method to the expensive and tedious nanofabrication techniques for industrial applications.

}, keywords = {Au Nanoparticles, chemical vapor deposition, Sb-SnO2 Hyperbranched Nanostructures}, issn = {1947-2935}, doi = {10.1166/sam.2009.1006}, author = {Sathe, Bhaskar R. and Patil, Mrudula and Walke, Pravin S. and Vivek, J. P. and Lele, Ashish K. and Pillai, Vijayamohanan K. and Mulla, Imtiaz S.} }