@article { ISI:000242931900034, title = {Field emission from oriented tin oxide rods}, journal = {Thin Solid Films}, volume = {515}, number = {4}, year = {2006}, month = {DEC}, pages = {1450-1454}, publisher = {ELSEVIER SCIENCE SA}, type = {Article}, address = {PO BOX 564, 1001 LAUSANNE, SWITZERLAND}, abstract = {

Tin oxide (SnO2) films were grown on silicon substrates by a wet chemical route. It was found from scanning electron microscopy investigations that oriented SnO2 rods normal to the substrates were obtained. Field emission studies were carried out in diode configuration in an all metal ultra high vacuum chamber at a base pressure similar to 1.33 x 10(-8) mbar. The {\textquoteleft}onset{\textquoteright} field required to draw 0.1 mu A/cm(2) current density from the emitter cathode was found to be similar to 3.4 V/mu m for SnO2 rods. The field emission current and applied field follows the Folwer-Nordheim relationship in low field regime. The observed results indicate that the field emission characteristics of chemically grown SnO2 structures are comparable to the vapor grown nanostructures. (c) 2006 Elsevier B.V. All rights reserved.

}, keywords = {field emission, microstructures, scanning electron microscopy, tin oxide}, issn = {0040-6090}, doi = {10.1016/j.tsf.2006.04.034}, author = {Deshpande, A. C. and Koinkar, Pankaj M. and Ashtaputre, S. S. and More, Mahendra A. and Gosavi, S. W. and Godbole, P. D. and Joag, Dilip S. and Kulkarni, S. K.} } @article { ISI:000302634800023, title = {Organization of cubic CeO2 nanoparticles on the edges of self assembled tapered ZnO nanorods via a template free one-pot synthesis: significant cathodoluminescence and field emission properties}, journal = {Journal of Materials Chemistry}, volume = {22}, number = {18}, year = {2012}, month = {MAR}, pages = {8887-8895}, publisher = {ROYAL SOC CHEMISTRY}, type = {Article}, address = {THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLAND}, abstract = {

The present investigation explores the controlled architecture of a CeO2-ZnO nanocomposite via a template-free, low temperature, facile single step solvothermal approach. This complex architecture depicts cubic single crystalline CeO2 nanoparticles (size similar to 15 nm) grown on the edges of tapered ZnO nanorods with definite orientations and alignments. The formation of wurtzite ZnO, cubic CeO2 and the coexistence of Ce3+ and Ce4+ on the surface of the CeO2-ZnO nanocomposites are confirmed using various characterization tools. The finding of such unique nanostructures by a facile method is exemplified by a plausible growth mechanism. Surprisingly, the aqueous mediated ultrasonication reaction conferred the formation of crystalline ZnO nanotubes of diameter similar to 50 nm. Spatially resolved cathodoluminescence spectra are obtained by linearly scanning an individual CeO2-ZnO nanorod along its length, which reveals the size-dependent surface effects. Interestingly, such hybrid CeO2-ZnO nanoarchitecture is observed to exhibit enhanced field emission properties, demonstrating better current stability as compared to other ZnO nanostructures. This is attributed mainly to strong surface interactions between the Ce-ionic species and the ZnO nanorods. Herein, a soft-chemical approach is used for the first time to architect a binary oxide nanostructure, which is otherwise accomplished using high temperature techniques, as reported elsewhere. Also, the present work not only gives insight into understanding the hierarchical growth behaviour of the CeO2-ZnO nanocomposite in a solution phase synthetic system, but also provides an efficient route to enhance the field emission performance of ZnO nanostructures, which could be extended to other potential applications, such as chemical sensors, optoelectronic devices and photocatalysts.

}, issn = {0959-9428}, doi = {10.1039/c2jm30226h}, author = {Warule, Sambhaji S. and Chaudhari, Nilima S. and Kale, Bharat B. and Patil, Kashinath R. and Koinkar, Pankaj M. and More, Mahendra A. and Murakami, Ri-ichi} } @article { ISI:000352315600048, title = {Biosynthesis of silver nanoparticles by using ganoderma-mushroom extract}, journal = {Modern Physics Letters B}, volume = {29}, number = {6-7, SI}, year = {2015}, month = {MAR}, pages = {1540047}, publisher = {WORLD SCIENTIFIC PUBL CO PTE LTD}, address = {5 TOH TUCK LINK, SINGAPORE 596224, SINGAPORE}, abstract = {

Present study reports the biochemical synthesis of silver nanoparticles (Ag-NPs) from aqueous medium by using the extract of medicinal mushroom Ganoderma, as a reducing and stabilizing agents. The Ag-NPs are prepared at room temperature by the reduction of Ag+ to Ag in aqueous solution of AgNO3. The resultant particles are characterized by using UV-visible spectroscopy, Fourier transform infrared (FTIR) spectroscopy and transmission electron microscopy (TEM) measurement techniques. The formation of Ag-NPs is confirmed by recording the UV-visible absorption spectra for surface plasmon resonance (SPR) where peak around 427 nm. The prominent changes observed in FTIR spectra supported the reduction of Ag+ to Ag. The morphological features of Ag-NPs are evaluated from HRTEM. The spherical Ag-NPs are observed in transmission electron microscopy (TEM) studies. The particle size distribution is found to be nearly uniform with average particle size of 2 nm. The Ag-NPs aged for 15, 30, 60 and 120 days showed no profound effect on the position of SPR peak in UV-visible studies, indicating the protecting/capping ability of medicinal mushroom Ganoderma in the synthesis of AgNPs.

}, keywords = {Biosynthesis, Ganoderma, medicinal mushroom, silver nanoparticles, UV-visible spectroscopy}, issn = {0217-9849}, doi = {10.1142/S0217984915400473}, author = {Ekar, S. U. and Khollam, Y. B. and Koinkar, Pankaj M. and Mirji, S. A. and Mane, R. S. and Naushad, M. and Jadhav, S. S.} }