@article { ISI:000232742000009, title = {Controlled growth of silicon nanocrystallites in silicon oxide matrix using 150 MeV Ag ion irradiation}, journal = {Nuclear Instruments \& Methods in Physics Research Section B-Beam Interactions with Materials and Atoms}, volume = {239}, number = {3}, year = {2005}, month = {SEP}, pages = {185-190}, publisher = {ELSEVIER SCIENCE BV}, type = {Article}, address = {PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS}, abstract = {

We report the synthesis of silicon nanocrystals grown in silicon oxide matrix by swift heavy ion irradiation. Thin films of silicon oxide (SiO(x)) are irradiated with 150 MeV silver ions at fluence varying from 5 x 10(11) to 1 x 10(13) ions/cm(2). The variation in the properties of silicon nanocrystals embedded in silicon oxide with varying fluence is studied. The energy of the photoluminescence peak corresponding to the silicon nanocrystals is found to be red shifted with increasing fluence. The trends in the broadening of the X-ray diffraction peak with decreasing fluence supports the controlled growth of silicon nanocrystals in silicon oxide matrix. The crystallite size of nanoclusters of silicon is seen to increase with increasing fluence. The results are discussed in view of the structural transformation, in SiO(x) matrix, caused by swift heavy ion irradiation. (c) 2005 Elsevier B.V. All rights reserved.

}, keywords = {oxide matrix, silicon nanocrystallites, swift heavy ion irradiation}, issn = {0168-583X}, doi = {10.1016/j.nimb.2005.04.069}, author = {Chaudhari, P. S. and Bhave, T. M. and Pasricha, R. and Singh, F. and Kanjilal, D. and Bhoraskar, S. V.} } @article { ISI:000229592000044, title = {Copper- and ligand-free sonogashira reaction catalyzed by Pd(0) nanoparticles at ambient conditions under ultrasound irradiation}, journal = {Journal of Organic Chemistry}, volume = {70}, number = {12}, year = {2005}, month = {JUN}, pages = {4869-4872}, publisher = {AMER CHEMICAL SOC}, type = {Article}, address = {1155 16TH ST, NW, WASHINGTON, DC 20036 USA}, abstract = {

The Sonogashira reaction proceeds at ambient temperature (30 degrees C) in acetone or room-temperature ionic liquid, 1,3-di-n-butylimidazolium tetrafluoroborate ([bbim]BF4), as solvent under ultrasound irradiation to give enhanced reaction rates, excellent chemoselectivity, and high yields in the absence of a copper cocatalyst and a phosphine ligand. TEM analysis showed the formation of stable, crystalline, and polydispersed Pd(0) nanoparticles as catalyst for the reaction.

}, issn = {0022-3263}, doi = {10.1021/jo0503815}, author = {Gholap, Atul R. and Venkatesan, K. and Pasricha, R. and Daniel, Thomas and Lahoti, Rajgopal J. and Srinivasan, K. V.} } @article { ISI:000228797100055, title = {Deposition and characterization of silver nano-films by a novel solid liquid interface reaction technique (SLIRT)}, journal = {Materials Letters}, volume = {59}, number = {14-15}, year = {2005}, month = {JUN}, pages = {1958-1961}, publisher = {ELSEVIER SCIENCE BV}, type = {Article}, address = {PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS}, abstract = {

Solid-liquid interface reaction technique (SLIRT) is used to deposit silver film on glass substrate. The solid film of silver nitrate is formed by modified spin coating method. This film is subsequently processed by dipping it in a reducing solution so as to initiate a reaction at the interface and ultimately transform it to totally silver film. In situ transformation of silver nitrate to silver is studied with respect to time spectrophotometrically. The characterization of silver film is done by various physicochemical techniques namely XRD, XPS, ED, TEM and UV visible spectroscopy. (c) 2005 Elsevier B.V. All rights reserved.

}, keywords = {Electron microscopy, Nano-Particles, solid-liquid interface reaction, thin film}, issn = {0167-577X}, doi = {10.1016/j.matlet.2005.02.035}, author = {Godbole, P. D. and Mitra, A. and Pasricha, R. and Mandale, A. B. and Patil, K. R.} } @article { ISI:000227158100004, title = {Formation of BaCrO4 nano crystallites within thermally evaporated sodium bis-2-ethylhexyl-sulfosuccinate and stearic acid thin films}, journal = {Journal of the American Ceramic Society}, volume = {88}, number = {1}, year = {2005}, month = {JAN}, pages = {24-27}, publisher = {AMER CERAMIC SOC}, type = {Article}, address = {735 CERAMIC PLACE, PO BOX 6136, WESTERVILLE, OH 43086-6136 USA}, abstract = {

This paper describes the growth of barium chromate (BaCrO4) nanocrystallites within thermally evaporated thin films of stearic acid (StA) and sodium bis-2-ethylhexyl-sulfosuccinate by a process of Ba2+ ion entrapment followed by in situ reaction CrO42- ions. Dense spherical assemblies of BaCrO4 nanocrystallites of very uniform size (similar to50 nm) were obtained within the two different host matrices. The spherical assemblies were composed of smaller (ca. 5-10 nm size) BaCrO4 crystals indicating that efficient size control over crystal size may be exercised by the matrix. Contact angle measurements of the BaCrO4-StA and BaCrO4-sodium bis-2-ethylhexyl-sulfosuccinate films indicated that they were hydrophobic, thus pointing to the possible role of hydrophobic interaction between the StA and sodium bis-2-ethylhexyl-sulfosuccinate monolayer-covered BaCrO4 crystals in the assembly process.

}, issn = {0002-7820}, doi = {10.1111/j..1551-2916}, author = {Rautaray, D. and Sinha, K. and Sainkar, S. R. and Pasricha, R. and Pavaskar, N. R. and Sastry, M.} } @article { ISI:000230823200014, title = {Growth of PbS nanopyramidal particulate films for potential applications in quantum-dot photovoltaics and nanoantennas}, journal = {Materials Research Bulletin }, volume = {40}, number = {8}, year = {2005}, month = {AUG}, pages = {1353-1360}, publisher = {PERGAMON-ELSEVIER SCIENCE LTD}, type = {Article}, address = {THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND}, abstract = {

We report a simple interfacial process called the liquid-liquid interface reaction technique (LLIRT) that leads to the formation of nanosized PbS particulate films with hitherto unreported pyramidal morphology. The resultant PbS films were characterized by transmission electron microscopy (TEM) with selected area electron diffraction (SAED), X-ray diffractometery (XRD), atomic force microscopy (AFM), near field scanning optical microscopy (NSOM) and UV-vis spectroscopy. The pyramidal morphology is speculated to originate from the preferred orientation of the 2 2 0 plane of cubic PbS. Our nanopyramidal PbS particulate films display remarkably sharp excitonic peak centered around 656 nm that accounts for a band gap of 1.8 eV suggesting, in turn, their potential application in QD photovoltaics. Interestingly, the feasibility of such nanopyramids to potentially act as nanoantennas (as revealed by the NSOM) is also suggested. (c) 2005 Elsevier Ltd. All rights reserved.

}, keywords = {Atomic force microscopy, Chemical synthesis, Electron microscopy, Nanostructures, Optical properties}, issn = {0025-5408}, doi = {10.1016/j.materresbull.2005.04.018}, author = {Hawaldar, Ranjit R. and Mulik, Uttam P. and Patil, K. and Pasricha, R. and Sathaye, S. and Lewis, A. and Amalnerkar, Dinesh P.} } @article { ISI:000231634800045, title = {Novel low-temperature synthesis of nanosized NiZn ferrite}, journal = {Journal of the American Ceramic Society}, volume = {88}, number = {9}, year = {2005}, month = {SEP}, pages = {2597-2599}, publisher = {BLACKWELL PUBLISHING}, type = {Article}, address = {9600 GARSINGTON RD, OXFORD OX4 2DQ, OXON, ENGLAND}, abstract = {

Nanosized NiZn ferrite powder is synthesized by a low-temperature method, using a unique combination of citric acid and glycine. An appropriate molar ratio of both citric acid and glycine offers a low-temperature synthetic route by incorporating the complexation behavior of citric acid and the combustion nature of glycine. Thermal decomposition/controlled autocatalytic combustion of the composite gel occurs at a low temperature of around 175 degrees C, with the evolution of a large amount of gases. Transmission electron microscopic studies showed that the average particle size of the ferrite obtained is similar to 2.5 nm, with a narrow size distribution. Uniformly distributed fine-grained microstructure with low porosity is obtained for a sample sintered at 1000 degrees C.

}, issn = {0002-7820}, doi = {10.1111/j.1551-2916.2005.00445.x}, author = {Verma, S. and Pradhan, S. D. and Pasricha, R. and Sainkar, S. R. and Joy, Pattayil Alias} } @article { ISI:000225750600004, title = {Novel polymer-inorganic solid-state reaction for the synthesis of CdS nanocrystallites}, journal = {Materials Letters}, volume = {59}, number = {5}, year = {2005}, month = {FEB}, pages = {554-559}, publisher = {ELSEVIER SCIENCE BV}, address = {PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS}, abstract = {

We offer a novel polymer-inorganic solid-state reaction route for the in situ generation of nanochalcogenide semiconductor in the network of polymer which itself acts as a chalcogen source. We have exemplified feasibility of this route by reacting CdI2 with engineering thermoplastic polyphenylene sulphide (PPS). These two reactants in 1:1 and 10:1 molar ratios were simply heated at the crystalline melting temperature of PPS. The resultant products were characterized by X-ray diffractometry, Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM, with selected area electron diffraction). The prima facie observations revealed the formation of cubic nanocrystallites of US with the particle size ranging from 6 to 20 nm entrapped in modified (cyclized) PPS matrix when the reactants were taken in 10:1 molar ratio. A tentative mechanism has been suggested for such hitherto unattempted solid-state reaction. (C) 2004 Elsevier B.V. All rights reserved.

}, keywords = {CdS nanocrystallites, Semiconductor, solid-state reaction, Thermoplastic polymer matrix}, issn = {0167-577X}, doi = {10.1016/j.matlet.2004.10.037}, author = {Kanade, K. G. and Hawaldar, Ranjit R. and Pasricha, R. and Radhakrishnan, S. and Seth, T. and Mulik, Uttam P. and Kale, B. B. and Amalnerkar, Dinesh P.} } @article { ISI:000234204300019, title = {Oriented growth of nanocrystalline gamma ferric oxide in electrophoretically deposited films}, journal = {Hyperfine Interactions}, volume = {160}, number = {1-4}, year = {2005}, note = {International Workshop on Nanomaterials, Magnetic Ions and Magnetic Semiconductors Studies mostly by Hyperfine Interactions, M S Univ Baroda, Phys Dept, Baroda, INDIA, FEB 10-14, 2004}, month = {JAN}, pages = {199-209}, publisher = {Springer, Van Godewijckstraat 30, 3311 GZ Dordrecht, Netherlands}, type = {Article, Proceedings Paper}, address = { M S Univ Baroda, Phys Dept, Baroda, INDIA}, abstract = {

Films of nanocrystalline gamma-Fe2O3 were deposited on silicon substrates by using the technique of electrophoretic deposition. The precursor powder was nanocrystalline gamma-Fe2O3, which was synthesized, using DC arc plasma in the oxygen ambient by vapour-vapour interaction in gas phase condensation; at a stabilized arc current of 40 A. This powder was characterized by X-ray diffraction, Transmission Electron Microscopy, Vibrating Sample Magnetometer and Mossbauer Spectroscopy. An increase in directional coercivity was observed in case of films deposited on silicon substrates, which is dramatically significant. Preferred orientation of almost similar sized nanocrystalline magnetic domains in deposited films is evident from the results of X-ray diffraction and Transmission Electron Microscopy results. The preferred alignment of the nanocrystallites seems to be responsible for the significant changes observed in magnetic properties of films.

}, issn = {0304-3843}, doi = {10.1007/s10751-005-9165-5}, author = {Bhave, T. M. and Balasubramanian, C. and Nagar, H. and Kulkarni, S. and Pasricha, R. and Bakare, P. P. and Date, Sadgopal K. and Bhoraskar, S. V.} } @article { ISI:000231573100016, title = {Polycondensation in liquid crystalline phases of nonionic surfactants. Kinetics and morphology}, journal = {Polymer}, volume = {46}, number = {19}, year = {2005}, month = {SEP}, pages = {7961-7968}, publisher = {ELSEVIER SCI LTD}, type = {Article}, address = {THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND}, abstract = {

We have investigated acid-catalyzed polycondensation of alkoxysilane monomers in liquid crystalline phases of nonionic CnEm surfactants. The liquid crystalline phase is retained when the monomers polymerize. The high molecular weight molecules formed phase separate from the mesophase and are subsequently organized by it to form micron-sized particles. A variety of particle morphologies are formed by organization of the polymer particles in the mesophase. For condensation of dimethyldimethoxysilane (DMS, with trimethoxysilane, TMS as crosslinker) in hexagonal and lamellar phases, specific reaction conditions, viz. slow condensation kinetics and low crosslink density, give rod-like particles in hexagonal phases and sheet-like structures in lamellar phases. However, when higher acid concentrations are used, the reaction kinetics accelerates and irregular particles form. Irregular particles also form when the fraction of trifunctional crosslinker is increased, and finally complex flower-like structures form for condensation of trimethoxysilane in the hexagonal phase. The particle morphology formed is crucially dependent on the details of the polycondensation rate, crosslinker density and surfactant-monomer/oligomer interactions. (c) 2005 Elsevier Ltd. All rights reserved.

}, keywords = {nonionic, surfactant, templated synthesis}, issn = {0032-3861}, doi = {10.1016/j.polymer.2005.07.001}, author = {Kumaraswamy, Guruswamy and Wadekar, M. N. and Agrawal, Vikrant V. and Pasricha, R.} } @article { ISI:000228760300034, title = {Polymerization in surfactant liquid crystalline phases}, journal = {Chemistry of Materials}, volume = {17}, number = {9}, year = {2005}, month = {MAY}, pages = {2460-2465}, publisher = {AMER CHEMICAL SOC}, type = {Article}, address = {1155 16TH ST, NW, WASHINGTON, DC 20036 USA}, abstract = {

We report the formation of cross-linked polysiloxane particles having rodlike and sheetlike morphologies by condensation of monomers in organized liquid crystalline mesophases of nonionic surfactants. The characteristic diffraction pattern obtained from the liquid crystalline surfactant assembly is preserved during polymer synthesis. The polymer colloids are rodlike when synthesized in a hexagonal mesophase and are sheetlike when synthesized in a lamellar mesophase. Interestingly, the size of the polymer particles is on the order of micrometers, viz. 3 orders of magnitude larger than the characteristic size of the surfactant mesophase. Thus, the polymers phase separate from the liquid crystalline phase during polymerization, and organize to resemble the mesophase geometry. The polymer particles are organized so as to minimize the elastic distortion of the surfactant mesophase after they phase separate. We speculate that the observed particle morphologies are formed due to the slow kinetics of polycondensation under our experimental conditions.

}, issn = {0897-4756}, doi = {10.1021/cm048240r}, author = {Wadekar, M. N. and Pasricha, R. and Gaikwad, A. B. and Kumaraswamy, Guruswamy} } @article { ISI:000228797100048, title = {Preparation of ferroelectric BaNb2O6 the urea method}, journal = {Materials Letters}, volume = {59}, number = {14-15}, year = {2005}, month = {JUN}, pages = {1929-1931}, publisher = {ELSEVIER SCIENCE BV}, type = {Article}, address = {PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS}, abstract = {

A precipitate was formed when an aqueous solution of BaCl2, NbF5 and urea in required ratio (the ratio of total metal cations to the urea is five) is heated on a water bath at 100 degrees C. This precipitate on decomposition at 600 degrees C yielded the nanocrystallites of BaNb2O6 (BN), as confirmed by X-ray diffraction study (XRD). This is a much lower temperature as compared to that prepared by traditional solid state method (1000 degrees C) as reported for the formation of BaNb2O6. Transmission electron microscope (TEM) investigations revealed that the average particle size is 85 nm for the calcined powders. The room temperature dielectric constant at 1 kHz is found to be 900. The ferroelectric hysteresis loop parameters of these samples were also studied. (c) 2005 Elsevier B.V. All rights reserved.

}, keywords = {Ceramics, Chemical synthesis, electronic material, ferroelectricity, Oxides}, issn = {0167-577X}, doi = {10.1016/j.matlet.2005.02.028}, author = {Dhage, S. R. and Pasricha, R. and Ravi, V.} } @article { ISI:000231605600022, title = {Silver nanoparticles of variable morphology synthesized in aqueous foams as novel templates}, journal = {Bulletin of Materials Science}, volume = {28}, number = {5}, year = {2005}, month = {AUG}, pages = {503-510}, publisher = {INDIAN ACADEMY SCIENCES}, type = {Article}, address = {C V RAMAN AVENUE, SADASHIVANAGAR, P B \#8005, BANGALORE 560 080, INDIA}, abstract = {

In this paper, we describe the synthesis of silver nanocrystals within aqueous foams as a template More specifically, we show that aqueous Ag+ ions may be electrostatically complexed with the anionic surfactants aerosol OT (sodium bis-2-ethylhexyl-sulfosuccinate, (AOT) and sodium dodecyl sulphate (SDS)) in a highly stable liquid foam. After drainage of the foam, the silver ions are reduced in situ by introducing sodium borohydride into the foam by capillary flow. This leads to the formation of silver nanoparticles of spherical, tape- and sheet-like morphology in the foam. The structure of the foam is extremely complex and presents reaction sites of different spatial extent. The differences in foam reaction-site geometry are believed to be responsible for the morphology variation in the silver nanoparticles observed. The silver nanoparticles are observed to be extremely stable in solution suggesting that the AOT or SDS molecules stabilize them. This approach appears promising for application in large-scale synthesis of nanoparticles and may be readily extended to other chemical compositions.

}, keywords = {Chemical synthesis, composites, foam, Intercalation, Nanoparticles}, issn = {0250-4707}, doi = {10.1007/BF02711244}, author = {Mandal, Sujata and Arumugam, S. K. and Pasricha, R. and Sastry, M.} } @article { ISI:000232886800008, title = {Synthesis and analysis of ZnO and CdSe nanoparticles}, journal = {Pramana-Journal of Physics}, volume = {65}, number = {4, SI}, year = {2005}, note = {1st National Conference on Nanoscience and Technology, Pune, INDIA, MAR 07-08, 2005}, month = {OCT}, pages = {615-620}, publisher = {INDIAN ACADEMY SCIENCES}, type = {Article}, address = {C V RAMAN AVENUE, SADASHIVANAGAR, P B \#8005, BANGALORE 560 080, INDIA}, abstract = {

Zinc oxide and cadmium selenide particles in the nanometer size regime have been synthesized using chemical routes. The particles were capped using thioglycerol in case of ZnO and 2-mercaptoethanol in case of CdSe to achieve the stability and avoid the coalescence. Zinc oxide nanoparticles were doped with europium to study their optical properties. A variety of techniques like UV-Vis absorption spectroscopy, X-ray diffraction (XRD), photoluminescence (PL), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FT-IR) and transmission electron microscopy (TEM) were used to carry out structural and spectroscopic characterizations of the nanoparticles.

}, keywords = {chemical capping, Doping, Nanoparticles, photoluminescence}, issn = {0304-4289}, doi = {10.1007/BF03010449}, author = {Ashtaputre, S. S. and Deshpande, Aparna and Marathe, Sayali and Wankhede, M. E. and Chimanpure, J. and Pasricha, R. and Urban, J. and Haram, Santosh K. and Gosavi, S. W. and Kulkarni, S. K.} } @article { ISI:000230877900020, title = {Synthesis of bismuth oxide nanoparticles by citrate gel method}, journal = {Ceramics International}, volume = {31}, number = {6}, year = {2005}, month = {JAN}, pages = {889-891}, publisher = {ELSEVIER SCI LTD}, type = {Article}, address = {THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND}, abstract = {

A mixture of bismuth nitrate and citric acid solution is taken in 1: 1 molar ratio and heated on hot water bath. A gel is formed on evaporation of the water, which on decomposition at 400 degrees C produces nanocrystalline Bi2O3 particles. Formation of nanocrystallites of Bi2O3 is confirmed by X-ray diffraction (XRD) study. Transmission electron microscope (TEM) investigations revealed that the average particle size is 50 nm for these powders. (c) 2004 Elsevier Ltd and Techna Group S.r.l. All rights reserved.

}, keywords = {Electron microscopy, powders : chemical preparation, X-ray methods}, issn = {0272-8842}, doi = {10.1016/j.ceramint.2004.09.002}, author = {Anilkumar, Mettu and Pasricha, R. and Ravi, V.} } @article { ISI:000227603500020, title = {Synthesis of bismuth oxide nanoparticles using bismuth nitrate and urea}, journal = {Ceramics International}, volume = {31}, number = {3}, year = {2005}, month = {JAN}, pages = {495-497}, publisher = {ELSEVIER SCI LTD}, address = {THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND}, abstract = {

A mixture of bismuth nitrate and urea is taken in 1:5 molar ratio and heated on hot water bath. A precipitate is formed on evaporation of the water which on decomposition at 400 degrees C produces nanocrystalline Bi2O3 particles. Formation of nano crystallites of Bi2O3 is confirmed by X-ray diffraction (XRD) study. Transmission electron microscopy (TEM) investigations revealed for these powders an average particle size of 50 nm. (c) 2004 Elsevier Ltd and Techna Group S.r.l. All rights reserved.

}, keywords = {calcination, Electron microscopy, X-ray methods}, issn = {0272-8842}, doi = {10.1016/j.ceramint.2004.006.013}, author = {Jha, Ratnesh Kumar and Pasricha, R. and Ravi, V.} } @article { ISI:000226803200008, title = {Synthesis of fine particles of ZnO at 100 degrees C}, journal = {Materials Letters}, volume = {59}, number = {7}, year = {2005}, month = {MAR}, pages = {779-781}, publisher = {ELSEVIER SCIENCE BV}, type = {Article}, address = {PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS}, abstract = {

A simple gel to crystal conversion route has been followed for the preparation of fine ZnO at 80-100 degreesC under refluxing conditions. Freshly prepared zinc hydroxide gel is allowed to crystallize under refluxing and stirring conditions for 4-6 It. Formation of fine crystallites of ZnO is confirmed by X-ray diffraction (XRD) study. Transmission electron microscope (TEM) investigations revealed that the average particle size is 100 nm for these powders. (C) 2004 Elsevier B.V All rights reserved.

}, keywords = {Ceramics, Chemical synthesis, Electron microscopy, Oxides, X-ray diffraction}, issn = {0167-577X}, doi = {10.1016/j.matlet.2004.11.019}, author = {Dhage, S. R. and Pasricha, R. and Ravi, V.} } @article { ISI:000227164000044, title = {Synthesis of Sr0.5Ba0.5Nb2O6 by urea method}, journal = {Materials Letters}, volume = {59}, number = {8-9}, year = {2005}, month = {APR}, pages = {1053-1055}, publisher = {ELSEVIER SCIENCE BV}, address = {PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS}, abstract = {

A precipitate was formed when an aqueous solution of SrCl2, BaCl2, NbF5 and urea in stoichiometric ratio (total metal cations to urea ratio is 5) is heated on a water bath.. This precipitate on decomposition at 750 degreesC yielded the nanocrystallites of ternary oxide, Sr0.5Ba0.5Nb2O6 (SBN) as confirmed by X-ray diffraction study (XRD). This is much lower temperature as compared to that prepared by traditional solid state method (1000 degreesC as reported for the formation of SBN ceramics. Transmission electron microscope (TEM) investigations revealed that the average particle size is 100 nm for the calcined powders. The room temperature dielectric constant at 1 kHz is found to be 1050. The ferroelectric hysteresis loop parameters of these samples were also studied. (C) 2004 Elsevier B.V. All rights reserved.

}, keywords = {Ceramics, Electron microscopy, ferroelectricity, Oxides}, issn = {0167-577X}, doi = {10.1016/j.matlet.2004.12.003}, author = {Dhage, S. R. and Pasricha, R. and Ravi, V.} } @article { ISI:000238298100027, title = {Co-precipitation technique for the preparation of ferroelectric BaBi2Ta2O9}, journal = {Materials Chemistry and Physics}, volume = {98}, number = {2-3}, year = {2006}, month = {AUG}, pages = {344-346}, publisher = {ELSEVIER SCIENCE SA}, type = {Article}, address = {PO BOX 564, 1001 LAUSANNE, SWITZERLAND}, abstract = {

A simple co-precipitation technique had been successfully applied for the preparation of pure ultrafine single phase BaBi2Ta2O9 (BBT). Ammonium hydroxide and ammonium oxalate were used to precipitate Ba2+, Bi3+ and Ta5+ cations simultaneously. No pyrochlore phase was found while heating powder at 800 degrees C and pure BaBi2Ta2O9 phase was found to be formed by X-ray diffraction. Particle size and morphology was studied by transmission electron spectroscopy (TEM). The room temperature dielectric constant at 1 kHz is 350. The ferroelectric hysteresis loop parameters of these samples were also studied. (c) 2005 Elsevier B.V. All rights reserved.

}, keywords = {Ceramics, Chemical synthesis, electronic material, ferroelectricity, Oxides}, issn = {0254-0584}, doi = {10.1016/j.matchemphys.2005.09.036}, author = {Dhage, S. R. and Pasricha, R. and Murugan, A. Vadivel and Ravi, V.} } @article { ISI:000242598200030, title = {Effect of a focusing electric field on the formation of arc generated carbon nanotubes}, journal = {Nanotechnology}, volume = {17}, number = {23}, year = {2006}, month = {DEC}, pages = {5895-5902}, publisher = {IOP PUBLISHING LTD}, type = {Article}, address = {DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND}, abstract = {

The effect of a focusing electric field on the formation of carbon nanotubes in a direct current arc-plasma is investigated. The hard deposits on the surface of the cathode are the main products, rich in multi-walled carbon nanotubes. It is seen that the focusing electric field has a distinct influence on the yield, purity and morphology of the nanotubes. The yield of the carbon nanotubes under the {\textquoteleft}focused field condition{\textquoteright} has been found to be higher than that derived from the normal electrode configuration. It has been observed that the deposition of carbonaceous soot on the reactor wall is considerably reduced on application of the focusing electric field. Transmission electron microscopy has been used to determine the morphology of the nanotubes. In addition, Raman spectroscopy has helped in distinguishing the graphene-like structures from the disordered carbon networks and helped in analysing the morphology of the tubes. Thermal analysis gave a qualitative estimation of the relative yield of carbon nanotubes within the cathode deposits and their thermal stabilities. The crystalline nature of the samples has been confirmed by x-ray diffraction analysis. The results clearly indicate that the focusing electric field confines the positively charged carbon precursors within the cathode-anode space causing high relative yield and purity and has a distinct effect on controlling the inner diameter of the as-synthesized carbon nanotubes.

}, issn = {0957-4484}, doi = {10.1088/0957-4484/17/23/030}, author = {Karmakar, Soumen and Nagar, Harshada and Pasricha, R. and Seth, T. and Sathe, V. G. and Bhoraskar, S. V. and Das, A. K.} } @article { ISI:000238030200026, title = {Electrochemical organization of monolayer protected gold nanoclusters on single-walled carbon nanotubes: significantly enhanced double layer capacitance}, journal = {Journal of Nanoscience and Nanotechnology}, volume = {6}, number = {5}, year = {2006}, month = {MAY}, pages = {1387-1391}, publisher = {AMER SCIENTIFIC PUBLISHERS}, type = {Article}, address = {25650 NORTH LEWIS WAY, STEVENSON RANCH, CA 91381-1439 USA}, abstract = {

This paper reports a novel electrochemical route for anchoring monolayer protected gold nanoclusters (size 8 +/- 0.2 nm) on single-walled carbon nanotube bundles, resulting in the formation of hybrid materials. Monolayer protected gold nanoclusters prepared by modified Brust synthesis route were organized on SWNT bundles by cycling-the potential in dichloromethane between -1 to +1 V at a scan rate of 50 mV/s. Monolayer protected nanoclusters in electrolyte solutions possess ionic space charge around them (double layer charging), making them suitable for organization on nanotube bundles, by tuning the electrostatic interactions. More significantly, analysis of the double layer capacitance of these hybrid materials shows almost ten times increase in capacitance compared to that of bare SWNT bundles. We believe that these hybrid materials are potentially useful in nanoelectronics.

}, keywords = {double layer capacitance, double layer charging, hybrid materials, monolayer protected gold nanoclusters, single-walled carbon nanotubes}, issn = {1533-4880}, doi = {10.1166/jnn.2006.323}, author = {Mahima, Subhramanyam and Chaki, N. K. and Sharma, J. and Kakade, Bhalchandra A. and Pasricha, R. and Rao, A. M. and Vijayamohanan, K.} } @article { ISI:000239975900022, title = {In situ optical emission spectroscopic investigations during arc plasma synthesis of iron oxide nanoparticles by thermal plasma}, journal = {IEEE Transactions on Plasma Science}, volume = {34}, number = {4, 1}, year = {2006}, month = {AUG}, pages = {1175-1182}, publisher = {IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC}, type = {Article}, address = {445 HOES LANE, PISCATAWAY, NJ 08855 USA}, abstract = {

Investigations using in situ precursor spectroscopy during the growth of nanoparticles of iron oxide by thermal plasma induced gas phase condensation method have been shown to be useful for correlating the size of nanoparticles with existing plasma parameters. The relative abundance of ionized Fe species inside the plasma plume is seen to directly establish the relation between particle size, arc current, arc length, and ambient pressure of the reacting oxygen gas. The argon plasma from a transferred arc reactor is made to impinge on the anode that is allowed to vaporize and react with oxygen. The spectral line profiles of both Ar and Fe along the plasma column during the synthesis of nanoparticles have been proved to be useful in understanding the growth mechanism. Band intensities of FeO molecular states indicated the inverse relation with particle sizes that have been correlated to the two competitive processes in which energy is released, namely: 1) one involving the radiative transition and 2) the other that of the growth by coagulation. Atomic Boltzmann plots are used for estimating the temperatures of the zones, whereas particle sizes have been inferred using transmission electron microscopic measurements.

}, keywords = {plasma arc device, plasma-materials processing applications, spectroscopy}, issn = {0093-3813}, doi = {10.1109/TPS.2006.878430}, author = {Banerjee, Indrani and Joshi, N. K. and Sahasrabudhe, S. N. and Kulkarni, Naveen V. and Karmakar, Soumen and Pasricha, R. and Ghorui, S. and Tak, Atul K. and Murthy, Shri P. S. S. and Bhoraskar, S. V. and Das, A. K.} } @article { ISI:000243157600086, title = {Physical manipulation of biological and chemical syntheses for nanoparticle shape and size control}, journal = {Applied Physics Letters}, volume = {89}, number = {26}, year = {2006}, month = {DEC}, pages = {Article No. 263105}, publisher = {AMER INST PHYSICS}, type = {Article}, address = {CIRCULATION \& FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA}, abstract = {

A nanosynthesis scheme is demonstrated which renders excellent control of nanoparticle shape, size, and dispersity in a solution based synthesis process. The scheme, termed as percolative microcavity synthesis, involves the use of a granular medium with percolative microcavities which facilitate nearly similar grain size/shape dependent reaction zones limiting intrinsic growth inhomogeneities, enabling particle size/shape control. The viability of the process is demonstrated for the synthesis of gold nanoparticles by a plant extract based biological method as well as a chemical method. (c) 2006 American Institute of Physics.

}, issn = {0003-6951}, doi = {10.1063/1.2424272}, author = {Ogale, Satishchandra B. and Ahmad, Absar and Pasricha, R. and Dhas, Vivek V. and Syed, A.} } @article { ISI:000235256200004, title = {Preparation of gamma-Fe2O3 nanoparticles using DC thermal arc-plasma route, their characterization and magnetic properties}, journal = {Scripta Materialia}, volume = {54}, number = {7}, year = {2006}, month = {APR}, pages = {1235-1240}, publisher = {PERGAMON-ELSEVIER SCIENCE LTD}, type = {Article}, address = {THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND}, abstract = {

gamma-Fe2O3 particles were prepared, for the first time, using a direct current thermal arc-plasma route. The powder was characterized using X-ray diffraction, Mossbauer spectroscopy, X-ray photoelectron spectroscopy, chemical analysis, vibrating sample magnetometry C and transmission electron microscopy. The high purity, stoichiometry and spherical morphology of the gamma-Fe2O3 particles (saturation magnetization = 79 emu g(-1) and coercivity = 348 Oe) were confirmed. (c) 2006 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

}, keywords = {chemical analysis, DC thermal arc-plasma route, maghemite, Mossbauer spectroscopy, XPS}, issn = {1359-6462}, doi = {10.1016/j.scriptamat.2005.12.029}, author = {Banerjee, Indrani and Khollam, Y. B. and Balasubramanian, C. and Pasricha, R. and Bakare, P. P. and Patil, K. R. and Das, A. K. and Bhoraskar, S. V.} } @article { ISI:000238086600005, title = {Radiation assisted synthesis of nanosized barium zirconate}, journal = {Radiation Physics and Chemistry}, volume = {75}, number = {7}, year = {2006}, month = {JUL}, pages = {755-759}, publisher = {PERGAMON-ELSEVIER SCIENCE LTD}, type = {Article}, address = {THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND}, abstract = {

This paper reports the synthesis of refractory barium zirconate using solid-state reactive precursors subjected to gamma-radiations of a Co-60 source. Influence of varying doses on the formation of cubic phase of BaZrO3 has been investigated with the stepwise analysis of the intermediate products by means of FT-IR, XRD and TGA techniques. TEM depicts the nanospherical nature of the BaZrO3 particles. (C) 2006 Elsevier Ltd. All rights reserved.

}, keywords = {Ceramics, gamma-radiation, Nanoparticles, perovskite, refractory, XRD}, issn = {0969-806X}, doi = {10.1016/j.radphyschem.2005.12.041}, author = {Athawale, Anjali A. and Chandwadkar, Asha J. and Karandikar, Prashant R. and Pasricha, R. and Bapat, Malini S.} } @article { ISI:000236922600002, title = {Room temperature synthesis of mesoporous aggregates of anatase TiO2 nanoparticles}, journal = {Materials Chemistry and Physics}, volume = {97}, number = {2-3}, year = {2006}, month = {JUN}, pages = {207-212}, publisher = {ELSEVIER SCIENCE SA}, type = {Article}, address = {PO BOX 564, 1001 LAUSANNE, SWITZERLAND}, abstract = {

The controlled hydrolysis reaction of titanium tetrabutoxide in presence of acetic acid in isopropanol, i.e. in non-aqueous media was adopted in the present work for the synthesis of nanocrystalline titania followed by aging at ambient conditions for longer duration. The powder XRD shows that the as-dried precursor (without any aging) is non-crystalline in nature. However, room temperature aging for longer duration \> 120 days not only helped to develop crystallinity in TiO2 nanoparticles but also led to the formation of their self-assembly towards mesoporous aggregates creating sponge like TiO2 nano-structure having high surface area similar to 250m (2) g(-1)and narrow pore size distribution of 4-5 nm. TEM observations revealed the generation of spherical TiO2 nanoparticles (4-5 nm) assembled to form stable spongy scaffold having porous network structure with pore size 5-6 nm. Also, presence of a pronounced hysteresis loop in BET isotherm is indicative of a 3D-intersection network of the pores of size 4-5 nm. Further heat-treatment to the aged precursor at 400 degrees C/2 h in air modify pore network structure due to sintering of TiO2 particles as is observed in TEM studies and lowering thereby the surface area to 125 m(2) g(-1) (c) 2005 Elsevier B.V. All rights reserved.

}, keywords = {Microstructure, porous materials, sol-gel processing, titania}, issn = {0254-0584}, doi = {10.1016/j.matchemphys.2005.02.014}, author = {Deshpande, S. B. and Potdar, H. S. and Khollam, Y. B. and Patil, K. R. and Pasricha, R. and Jacob, Nalini E.} } @article { ISI:000248795100038, title = {Titania nanoparticles synthesis in mesoporous molecular sieve MCM-41}, journal = {Journal of Colloid and Interface Science}, volume = {314}, number = {1}, year = {2007}, month = {OCT}, pages = {310-316}, publisher = {ACADEMIC PRESS INC ELSEVIER SCIENCE}, type = {Article}, address = {525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA}, abstract = {

Nanocrystalline titanium oxide (TiO2) is one of the most useful oxide material, because of its widespread applications in photocatalysis, solar energy conversion, sensors and optoelectronics. The control of particle size and monodispersity of TiO2 nanoparticles is a challenging task. The use of MCM-41, an inorganic template of uniform pore size (2-10 nm), can overcome this difficulty and produce stable nanoparticles of uniform size and shape. Here, we demonstrate the synthesis of titania nanoparticles inside the pores of silica based MCM-41 forming a TiO2/Si-MCM composite. Composites are formed in the alcoholic medium by incipient wetness impregnation method. Titania particles of average 3 nm size are obtained. Effect of silica and titania precursors on the quality of nanoparticles has been investigated. The characterization of titania-MCM-41 composites has been carried out using a variety of techniques like UV-vis absorption spectroscopy, X-ray diffraction, FT-IR spectroscopy, X-ray photoelectron spectroscopy, transmission electron microscopy and photoluminescence spectroscopy. It has been found that the titania particles are co-ordinated with Si-MCM by Si-O-Ti covalent bond. (C) 2007 Elsevier Inc. All rights reserved.

}, keywords = {incipient wetness impregnation, Mesoporous material, template, titania}, issn = {0021-9797}, doi = {10.1016/j.jcis.2007.05.069}, author = {Lihitkar, N. B. and Abyaneh, Majid Kazemian and Samuel, V. and Pasricha, R. and Gosavi, S. W. and Kulkarni, S. K.} } @article { ISI:000258965100011, title = {Mossbauer spectroscopic investigations of nanophase iron oxides synthesized by thermal plasma route}, journal = {Materials Characterization}, volume = {59}, number = {9}, year = {2008}, month = {SEP}, pages = {1215-1220}, publisher = {ELSEVIER SCIENCE INC}, address = {360 PARK AVE SOUTH, NEW YORK, NY 10010-1710 USA}, abstract = {

Magnetic nanoparticles of iron oxide were synthesized by transferred arc plasma induced gas phase condensation method. Structural, morphological and magnetic studies of the as synthesized powder were carried out using X-ray diffraction, transmission electron microscopy and Mossbauer spectroscopy. These studies have revealed the simultaneous nucleation and condensation of different magnetic phases with a broad size distribution of the nanoparticles which is peaked at 30-50 nm and ranges from 10 nm to 80 nm. 57 Fe Mossbauer spectra recorded at various temperatures (5 K-300 K) in presence of external magnetic field (at 5 K) have suggested the presence of different phases of iron oxide with sizable amounts of gamma-Fe2O3 and alpha-Fe2O3 in addition to Fe3O4. The relative concentrations of these phases have been obtained by a self consistent spectral area analysis and were found to be 44:22:34 (\%). (C) 2007 Elsevier Inc. All rights reserved.

}, keywords = {iron oxides, Mossbauer spectroscopy, phase analysis, plasma synthesis}, issn = {1044-5803}, doi = {10.1016/j.matchar.2007.10.003}, author = {Nagar, Harshada and Kulkarni, Naveen V. and Karmakar, Soumen and Sahoo, B. and Banerjee, Indrani and Chaudhari, P. S. and Pasricha, R. and Das, A. K. and Bhoraskar, S. V. and Date, Sadgopal K. and Keune, W.} }