@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:000241767100009, title = {Eu3+ doped lanthanum oxide nanowhiskers: microwave hydrothermal synthesis, characterization and photoluminescence properties}, journal = {Journal of Physics D-Applied Physics}, volume = {39}, number = {18}, year = {2006}, month = {SEP}, pages = {3974-3977}, publisher = {IOP PUBLISHING LTD}, type = {Article}, address = {DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND}, abstract = {

We report here a straightforward and rapid microwave - hydrothermal route providing an easy synthesis of Eu3+ doped La2O3 nanowhiskers. The nanostructured Eu3+ doped La2O3 is characterized by x-ray diffraction studies, scanning electron microscopy and photoluminescence (PL). The emission spectrum shows transitions from the excited 5D(0) state to F-7(J) (J = 0, 1, 2, 3, 4) levels of the Eu3+ ion. The most intense peak around 611 nm is due to the D-5(0) -\> F-7(2) transition, expected from the Judd-Ofelt selection rules. PL spectra measurements demonstrate that the lanthanum oxide nanowhisker shows higher PL intensity.

}, issn = {0022-3727}, doi = {10.1088/0022-3727/39/18/008}, author = {Murugan, A. Vadivel and Viswanath, Annamraju Kasi and Kakade, Bhalchandra A. and Ravi, V. and Saaminathan, V.} } @article { ISI:000240680300119, title = {Photoluminescence studies of Eu3+ doped Y2O3 nanophosphor prepared by microwave hydrothermal method}, journal = {Applied Physics Letters}, volume = {89}, number = {12}, year = {2006}, month = {SEP}, pages = {123120}, publisher = {AMER INST PHYSICS}, type = {Article}, address = {CIRCULATION \& FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA}, abstract = {

In this letter, the authors report the photoluminescence studies of Eu3+ doped Y2O3 nanorods, which have been synthesized by rapid microwave hydrothermal route within 6 min. The nanostructured Eu3+ doped Y2O3 is characterized by x-ray diffraction, transmission electron microscopy, and photoluminescence. The emission spectrum shows transitions from the excited 5D(0) state to F-7(J) (J=0,1,2,3,4) levels of the Eu3+ ion. The most intense peak around 612 nm is due to the D-5(0)-\> F-7(2) transition, expected from the Judd-Ofelt selection rules [B. R. Judd, Phys. Rev. 127, 750 (1962); G. S. Ofelt, J. Chem. Phys. 37, 511 (1962)]. Photoluminescence measurements demonstrated that the nanocrystalline Eu3+:Y2O3 phase shows higher photoluminescence intensity. (c) 2006 American Institute of Physics.

}, issn = {0003-6951}, doi = {10.1063/1.2356694}, author = {Murugan, A. Vadivel and Viswanath, Annamraju Kasi and Ravi, V. and Kakade, Bhalchandra A. and Saaminathan, V.} } @article { ISI:000238294800037, title = {Suppression of electron-transfer characteristics of ferrocene by OTS monolayer on a silicon/electrolyte interface}, journal = {Journal of Colloid and Interface Science}, volume = {299}, number = {2}, year = {2006}, month = {JUL}, pages = {777-784}, publisher = {ACADEMIC PRESS INC ELSEVIER SCIENCE}, type = {Article}, address = {525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA}, abstract = {

The passivating behavior of self-assembled monolayers (SAMs) of octadecyltrichlorosilane (OTS) on an n-type Si(100) electrode with and without a redox species like ferrocene in a polar non-aqueous medium has been investigated using techniques like contact angle measurements, Fourier transform infrared (FTIR) spectroscopy and X-ray photoelectron spectroscopy (XPS) to understand the role of the monolayer. The electron-transfer behavior of ferrocene is found to be drastically affected by the presence of monolayer and the reasons for these are analyzed as a function of the change in resistance, dielectric thickness and coverage of the monolayer. Electrochemical impedance analysis in the presence of ferrocene gives the monolayer coverage as 0.998 and the apparent rate constant calculated from this gives 4.85 x 10(-12) cm s(-1) in comparison with 4.4 x 10(-8) cm s(-1) for a similar electrode without any monolayer. A positive shift of 200 mV in the flat-band potential after monolayer formation also suggests the covalent coupling of the silane nionolayer offering a protective barrier. (c) 2006 Elsevier Inc. All rights reserved.

}, keywords = {cyclic voltammetry, ferrocene, impedance analysis, octadecyltrichlorosilane (OTS), rate constant, self-assembled monolayer (SAM)}, issn = {0021-9797}, doi = {10.1016/j.jcis.2006.03.013}, author = {Kulkarni, S. A. and Kakade, Bhalchandra A. and Mulla, Imtiaz S. and Pillai, V. K.} } @article { ISI:000243695000025, title = {Synthesis and characterization of mesoporous carbon through inexpensive mesoporous silica as template}, journal = {Microporous and Mesoporous Materials}, volume = {98}, number = {1-3}, year = {2007}, month = {JAN}, pages = {189-199}, publisher = {ELSEVIER SCIENCE BV}, type = {Article}, address = {PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS}, abstract = {

Mesoporous silica materials have been synthesized through sol-gel reaction using inexpensive sodium silicate as source of silica and low cost hydroxy carboxylic acid compounds as templates/pore forming agents. The material measured surface area of 1014 m(2)/g, pore diameter of 65 angstrom and pore volume of 1.4 cc/g when parameters like time and temperature of synthesis along with mole ratio of TA/SiO(2) were optimized. Here TA stands for tartaric acid. Carbonization of sucrose inside the pores of above silica material at 900 degrees C followed by removal of silica framework using aqueous ethanoic solution of NaOH gave rise to mesoporous carbon material. The resulting materials were characterized by N(2)-sorption, FTIR spectroscopy, X-ray diffraction, transmission electron microscopy, X-ray photoelectron spectroscopy, thermal analysis and cyclic voltammetry. Three dimensional interconnecting wormhole channel arrangement of mesoporous silica template leads to mesoporous carbon replica with surface area of 1200 m(2)/g. X-ray photoelectron spectroscopic study (XPS) of the mesoporous carbon material shows the concentration of carbon atom in the range of 97-98\% with 1-2\% oxygen and negligible amount of silica. The electrochemical double layer capacitance behavior of carbon material with the specific capacitance value of 88.0 F/g at the scan rate of 1 mV/s appears to be promising. (C) 2006 Elsevier Inc. All rights reserved.

}, keywords = {Electrochemical properties, hydroxy carboxylic acid, mesoporous carbon, Mesoporous silica, sodium silicate}, issn = {1387-1811}, doi = {10.1016/j.micromeso.2006.09.003}, author = {Karandikar, Prashant R. and Patil, K. R. and Mitra, A. and Kakade, Bhalchandra A. and Chandwadkar, Asha J.} } @article { ISI:000255728500004, title = {Efficient route towards the covalent functionalization of single walled carbon nanotubes}, journal = {Applied Surface Science}, volume = {254}, number = {16}, year = {2008}, month = {JUN}, pages = {4936-4943}, publisher = {ELSEVIER SCIENCE BV}, type = {Article}, address = {PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS}, abstract = {

A simple and efficient method of chemical functionalization of both single and multiwalled carbon nanotubes has been discussed to give enhanced water solubility by rapidly and efficiently generating an appreciable amount of hydrophilic functional groups using microwave radiation. Surface functionalization containing more than 30 wt\% of oxygen has been achieved, resulting into solubility of 2-5 mg/mL. Further covalent functionalization of such soluble SWNTs provides a remarkable degree of aniline functionalization through amidation, where the formation of polyaniline has been avoided. Functionalization of SWNTs is confirmed by techniques like electron microscopy, Fourier transform infrared spectroscopy, thermogravimetry, Raman spectroscopy, cyclic voltammetry and impedance spectroscopy. Electrochemical analysis suggests an enhanced double layer capacitance (similar to 110 F/g) of nanotubes after microwave treatment. Aniline functionalization of SWNTs shows possible variations on the nanotube topography with concomitant formation of a dynamic polymer layer on the nanotube surface. (C) 2008 Elsevier B.V. All rights reserved.

}, keywords = {Carbon nanotubes, Functionalization, Microwave, solubility}, issn = {0169-4332}, doi = {10.1016/j.apsusc.2008.01.148}, author = {Kakade, Bhalchandra A. and Pillai, Vijayamohanan K.} } @article { ISI:000259140200017, title = {Electric field induced, superhydrophobic to superhydrophilic switching in multiwalled carbon nanotube papers}, journal = {Nano Letters}, volume = {8}, number = {9}, year = {2008}, month = {SEP}, pages = {2693-2696}, publisher = {AMER CHEMICAL SOC}, type = {Article}, address = {1155 16TH ST, NW, WASHINGTON, DC 20036 USA}, abstract = {

Superhydrophobic multiwalled carbon nanotube bucky paper, fabricated after ozonolysis, shows fascinating electrowetting behavior, which could be remarkably tuned by changing key solution variables like the ionic strength, the nature of the electrolyte, and the pH of the water droplet. More significantly, the droplet behavior can be reversibly switched between superhydrophobic, Cassie-Baxter state to hydrophilic, Wenzel state by the application of an electric field, especially below a threshold value.

}, issn = {1530-6984}, doi = {10.1021/nl801012r}, author = {Kakade, Bhalchandra A. and Mehta, Rutvik and Durge, Apurva and Kulkarni, Sneha and Pillai, Vijayamohanan} } @article { ISI:000257231200057, title = {Enhanced field emission from hexagonal rhodium nanostructures}, journal = {Applied Physics Letters}, volume = {92}, number = {25}, year = {2008}, month = {JUN}, pages = {253106}, publisher = {AMER INST PHYSICS}, type = {Article}, address = {CIRCULATION \& FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA}, abstract = {

Shape selective synthesis of nanostructured Rh hexagons has been demonstrated with the help of a modified chemical vapor deposition using rhodium acetate. An ultralow threshold field of 0.72 V/mu m is observed to generate a field emission current density of 4 x 10(-3) mu A/cm(2). The high enhancement factor (9325) indicates that the origin of electron emission is from nanostructured features. The smaller size of emitting area, excellent current density, and stability over a period of more than 3 h are promising characteristics for the development of electron sources. (C) 2008 American Institute of Physics.

}, issn = {0003-6951}, doi = {10.1063/1.2943657}, author = {Sathe, Bhaskar R. and Kakade, Bhalchandra A. and Mulla, Imtiaz S. and Pillai, Vijayamohanan K. and Late, Dattatray J. and More, Mahendra A. and Joag, Dilip S.} } @article { ISI:000258800700002, title = {Highly selective catalytic hydrogenation of arenes using rhodium nanoparticles supported on multiwalled carbon nanotubes}, journal = {Journal of Physical Chemistry C}, volume = {112}, number = {35}, year = {2008}, month = {SEP}, pages = {13317-13319}, publisher = {AMER CHEMICAL SOC}, type = {Article}, address = {1155 16TH ST, NW, WASHINGTON, DC 20036 USA}, abstract = {

Rhodium nanoparticles (RhNPs; 4.9 +/- 0.4 nm) supported on multiwalled carbon nanotubes (Rh/MWNT), prepared by simple microwave treatment, show a remarkable catalytic activity for arene hydrogenation with enhanced turnover numbers of similar to 10000; disubstituted arenes show selective conversion of thermodynamically less favorable cis products (\>80\%). A series of arenes have been tested using various Rh-based catalysts, and a comparison of the results with that of reported rhodium catalysts shows unique selectivity under mild conditions.

}, issn = {1932-7447}, doi = {10.1021/jp804843h}, author = {Kakade, Bhalchandra A. and Sahoo, Suman and Halligudi, Shivappa B. and Pillai, Vijayamohanan K.} } @article { ISI:000255627700001, title = {High-purity synthesis of scrolled mats of multi-walled carbon nanotubes using temperature modulation}, journal = {Carbon}, volume = {46}, number = {4}, year = {2008}, month = {APR}, pages = {567-576}, publisher = {PERGAMON-ELSEVIER SCIENCE LTD}, type = {Article}, address = {THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND}, abstract = {

Felt-like mats (6-7 mu m thick) of multimalled carbon nanotubes wrapped into scrolls have been synthesized by chemical vapor deposition from a toluene-ferrocene mixture using a temperature ramp from 680 degrees C to 550 degrees C in hydrogen-argon atmosphere. Thermogravimetric analysis reveals a very low catalyst content of ca. 1.25 wt\% in the as-synthesized sample while, X-ray photo electron and Raman spectroscopies suggest the results matching with that of multiwalled carbon nanotubes. Considering, different time scales of various reactions and the diffusion of different reactants and products a tentative base growth mechanism has been proposed as per the available characterization data in conjunction with possible scrolling effects. Thermal expansion effects could explain a tentative mechanism for rolling action of sheets. 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 0.33 and 1.03 meV corresponding to two temperature ranges respectively. Cyclic voltammetry and electrochemical impedance analysis show a reversible redox behavior due to very low catalyst content and an irreversible etching of the Fe catalyst after acid treatment. (C) 2007 Elsevier Ltd. All rights reserved.

}, issn = {0008-6223}, doi = {10.1016/j.carbon.2007.12.020}, author = {Kakade, Bhalchandra A. and Allouche, Hatem and Mahima, Subhramanyam and Sathe, Bhaskar R. and Pillai, Vijayamohanan K.} } @article { ISI:000261262000024, title = {Invertase inhibition based electrochemical sensor for the detection of heavy metal ions in aqueous system: application of ultra-microlelectrode to enhance sucrose biosensor{\textquoteright}s sensitivity}, journal = {Biosensors \& Bioelectronics}, volume = {24}, number = {4}, year = {2008}, month = {DEC}, pages = {657-664}, publisher = {ELSEVIER ADVANCED TECHNOLOGY}, type = {Article}, address = {OXFORD FULFILLMENT CENTRE THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND}, abstract = {

We are reporting fabrication and characterization of electrochemical sucrose biosensor using ultra-microelectrode (UME) for the detection of heavy metal ions (Hg(II), Ag(I), Pb(II) and Cd(II)). The working UME, with 25 mu m diameter, was modified with invertase (INV, EC: 3.2.1.26) and glucose oxidase (GOD, EC: 1.1.3.4) entrapped in agarose-guar gum. The hydrophilic character of the agarose-guar gum composite matrix was checked by water contact angle measurement. The atomic force microscopy (AFM) images of the membranes showed proper confinement of both the enzymes during co-immobilization. The dynamic range for sucrose biosensor was achieved in the range of 1 x 10(-10) to 1 x 10(-7) M with lower detection limit 1 x 10(-10) M at pH 5.5 with 9 cycles of reuse. The spectrophotometric and electrochemical studies showed linear relationship between concentration of heavy metal ions and degree of inhibition of invertase. The toxicity sequence for invertase using both methods was observed as Hg(2+) \> Pb(2+) \> Ag(+) \> Cd(2+). The dynamic linear range for mercury using electrochemical biosensor was observed in the range of 5 x 10(-10) to 12.5 x 10(-10) M for sucrose. The lower detection limit for the fabricated biosensor was found to be 5 x 10(-10) M. The reliability of the electrochemical biosensor was conformed by testing the spike samples and the results were comparable with the conventional photometric DNSA method. (C) 2008 Elsevier B.V. All rights reserved.

}, keywords = {Co-immobilization, Electrochemical biosensor, Heavy metal ions, Invertase (INV)-glucose oxidase (GOD), Mercury, Ultra-microelectrode (UME)}, issn = {0956-5663}, doi = {10.1016/j.bios.2008.06.027}, author = {Bagal-Kestwal, Dipali and Karve, Meena S. and Kakade, Bhalchandra A. and Pillai, Vijayamohanan K.} } @article { ISI:000262377000014, title = {Near-complete phase transfer of single-wall carbon nanotubes by covalent functionalization}, journal = {Journal of Chemical Sciences}, volume = {120}, number = {6}, year = {2008}, note = {International Conference on Molecules and Materials - New Directions, Bangalore, INDIA, DEC 04, 2008}, month = {NOV}, pages = {599-606}, publisher = {INDIAN ACAD SCIENCES}, address = {C V RAMAN AVENUE, SADASHIVANAGAR, P B \#8005, BANGALORE 560 080, INDIA}, abstract = {

We describe here an efficient phase transfer of single wall carbon nanotubes (SWNTs) from aqueous to non-aqueous media using a unique amide functionalization route, where water soluble SWNTs (2.6 mg/mL) are effectively transferred to solvents like chloroform, toluene and CS(2). A maximum of 30 wt\% of oxygenated groups have been generated on the side walls by rapid microwave treatment, leading to a solubility of more than 2.6 mg/mL in water. Approximate surface amine coverage of 50\% has been accomplished after oxalyl chloride treatment as inferred from thermogravimetry and X-ray photoelectron spectroscopy by controlling several key parameters associated with the extent of functionalization including purity of the sample, temperature and time.

}, keywords = {Carbon nanotubes, microscopy, Microwave, Nanostructures, solubility of SWNTs}, issn = {0253-4134}, doi = {10.1007/s12039-008-0091-3}, author = {Kakade, Bhalchandra A. and Patil, Sanjay and Sathe, Bhaskar and Gokhale, Suresh and Pillai, Vijayamohanan} } @article { ISI:000254869800024, title = {Polymer electrolyte fuel cells using nafion-based composite membranes with functionalized carbon nanotubes}, journal = {Angewandte Chemie-International Edition}, volume = {47}, number = {14}, year = {2008}, month = {FEB}, pages = {2653-2656}, publisher = {WILEY-V C H VERLAG GMBH}, address = {PO BOX 10 11 61, D-69451 WEINHEIM, GERMANY}, keywords = {fuel cells, membranes, nanotubes, Polymers, proton transport}, issn = {1433-7851}, doi = {10.1002/anie.200704343}, author = {Kannan, Ramaiyan and Kakade, Bhalchandra A. and Pillai, Vijayamohanan K.} } @article { ISI:000256058000039, title = {Tuning the transport properties of Poly(oxyethylene)bisamine - Nafion polyelectrolyte complexes by dielectric manipulation}, journal = {Macromolecules}, volume = {41}, number = {10}, year = {2008}, month = {MAY}, pages = {3653-3658}, publisher = {AMER CHEMICAL SOC}, type = {Article}, address = {1155 16TH ST, NW, WASHINGTON, DC 20036 USA}, abstract = {

Polyelectrolyte complexes (PECs) of Nafion-H+, a perfluorosulfonic acid ionomer, and Poly(oxyethylene)bisamine (Polyox) were synthesized, and the effect of electrostatic interactions on the physicochemical properties of the individual components was studied using a combination of spectroscopic and electrochemical techniques. More specifically, the pristine PECs were extensively characterized using viscosity, surface tension, and pH measurements and diffuse reflectance Fourier transform infrared (DRIFT) spectroscopy and their transport properties were investigated using cyclic voltammetry and electrochemical impedance spectroscopy, by employing [Fe(CN)(6)](3-) as a redox probe. Acid-base interaction between Nafion and Polyox is evident from pH measurements of the blend solutions, which indicate salt formation at a 50:50 composition, supported further by the existence of a maximum in the plot of surface tension versus blend composition. DRIFT spectra of the PEC membranes indicate subtle changes in the ionic environment and a transition from a state of medium hydration to a partially dehydrated state of the parent ionomer, Nation, after complexation with Polyox. Further evidence for polyelectrolyte-polyelectrolyte association is obtained from cyclic voltammetry, which shows that the interaction between the redox active chromophore, [Fe(CN)(6)](3-), and the pendent sulfonate groups of Nafion is minimized by complexation with the oppositely charged polyelectrolyte Polyox. The water-soluble nature of these PECs along with the tunable range of properties with blend composition could qualify them as suitable candidates for developing stimuli-responsive polymer systems for pharmaceutical and environmental applications.

}, issn = {0024-9297}, doi = {10.1021/ma7028677}, author = {Parthasarathy, Meera and Kakade, Bhalchandra A. and Pillai, Vijayamohanan K.} } @article { ISI:000253512400006, title = {Tuning the wetting properties of multiwalled carbon nanotubes by surface functionalization}, journal = {Journal of Physical Chemistry C}, volume = {112}, number = {9}, year = {2008}, month = {MAR}, pages = {3183-3186}, publisher = {AMER CHEMICAL SOC}, type = {Article}, address = {1155 16TH ST, NW, WASHINGTON, DC 20036 USA}, abstract = {

A simple strategy of chemical functionalization is employed here for controlling the wettability of multiwalled carbon nanotube films from superhydorphobic (156 degrees) to nearly hydrophilic (40 degrees), which further shows superhydrophilicity with a water contact angle of about 0 degrees within 2 s. The hydrophobic surface (water contact angle 145 degrees) in case of nitric-acid-treated MWCNT bucky paper shows an unusual pinning action even at a tilt angle of 45 degrees, following Wenzel behavior of the surface. The variation in the wetting properties of MWCNT bucky paper using such surface designing strategies provides controlled heterogeneity on the surface with no or minimal effect on surface roughness.

}, issn = {1932-7447}, doi = {10.1021/jp711657f}, author = {Kakade, Bhalchandra A. and Pillai, Vijayamohanan K.} } @article { ISI:000269310600079, title = {Ultrafast switching time and third order nonlinear coefficients of microwave treated single walled carbon nanotube suspensions}, journal = {Journal of Nanoscience and Nanotechnology}, volume = {9}, number = {9}, year = {2009}, note = {International Conference on Nanoscience and Technology, Chennai, INDIA, FEB 27-29, 2008}, month = {SEP}, pages = {5550-5554}, publisher = {AMER SCIENTIFIC PUBLISHERS}, address = {25650 NORTH LEWIS WAY, STEVENSON RANCH, CA 91381-1439 USA}, abstract = {

Microwave treated water soluble and amide functionalized single walled carbon nanotubes have been investigated using femtosecond degenerate pump-probe and nonlinear transmission experiments. The time resolved differential transmission using 75 femtosecond pulse with the central wavelength of 790 nm shows a bi-exponential ultrafast photo-bleaching with time constants of 160 fs (130 fs) and 920 fs (300 fs) for water soluble (amide functionalized) nanotubes. Open and closed aperture z-scans show saturation absorption and positive (negative) nonlinear refraction for water soluble (amide functionalized) nanotubes. Two photon absorption coefficient, beta(0) similar to 250 cm/GW (650 cm/GW) and nonlinear index, gamma similar to 15 cm(2)/pW (-30 cm(2)/pW) are obtained from the theoretical fit in the saturation limit to the data for two types of nanotubes.

}, keywords = {Nonlinear Optical Coefficients, SWCNT, Ultra-Fast Switching}, issn = {1533-4880}, doi = {10.1166/jnn.2009.1184}, author = {Kamaraju, N. and Kumar, Sunil and Karthikeyan, B. and Kakade, Bhalchandra A. and Pillai, Vijayamohanan K. and Sood, A. K.} } @article { ISI:000281153600066, title = {High current density, low threshold field emission from functionalized carbon nanotube bucky paper}, journal = {Applied Physics Letters}, volume = {97}, number = {7}, year = {2010}, month = {AUG}, pages = {073102}, publisher = {AMER INST PHYSICS}, address = {CIRCULATION \& FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA}, abstract = {

Field emission studies of bucky paper of multiwalled carbon nanotubes (MWNTs), prepared after microwave (MW) assisted acid functionalization are reported along with a comparison with that of {\textquoteleft}{\textquoteleft}as-grown{\textquoteright}{\textquoteright} sample. MW treated bucky papers reveal an interesting linear field emission behavior in Fowler-Nordheim plot. The field emission currents at preset value are found to be remarkably stable over a period of more than 3 h sustaining current densities of 4.9 mA/cm(2) and 8.5 mA/cm(2) for {\textquoteleft}{\textquoteleft}as-grown{\textquoteright}{\textquoteright} and functionalized sample, respectively. The enhancement in the field emission due to functionalization has been discussed in terms of tip opening and defect induced charge transport caused by intershell and intertubular interaction. (C) 2010 American Institute of Physics. [doi:10.1063/1.3479049]

}, keywords = {Carbon nanotubes, current density, field emission, fullerenes}, issn = {0003-6951}, doi = {10.1063/1.3479049}, author = {Kakade, Bhalchandra A. and Pillai, Vijayamohanan K. and Late, Dattatray J. and Chavan, Padmakar G. and Sheini, Farid J. and More, Mahendra A. and Joag, Dilip S.} } @article { ISI:000280514500009, title = {Synthesis of Rh-carbon nanotube based heterostructures and their enhanced field emission characteristics}, journal = {Chemical Communications}, volume = {46}, number = {31}, year = {2010}, month = {JUL}, pages = {5671-5673}, publisher = {ROYAL SOC CHEMISTRY}, address = {THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLAND}, abstract = {

Selective decoration of Rh nanospheres on acid functionalized carbon nanotubes has been demonstrated using Al as a sacrificial substrate. Remarkable field emission has been observed for this heterostructure as a high current density of 170 mu A cm(-2) is generated at an ultra-low threshold of 300 V mu m(-1), compared to much smaller values for Rh nanospheres and carbon nanotubes separately.

}, issn = {1359-7345}, doi = {10.1039/c0cc01532f}, author = {Sathe, Bhaskar R. and Kakade, Bhalchandra A. and Kushwaha, Ajay and Aslam, Mohammed and Pillai, Vijayamohanan K.} } @article { ISI:000287176600009, title = {Carbon nanotube-modified sodium dodecyl sulfate-polyacrylamide gel electrophoresis for molecular weight determination of proteins}, journal = {Analytical Biochemistry}, volume = {409}, number = {2}, year = {2011}, month = {FEB}, pages = {230-235}, publisher = {ACADEMIC PRESS INC ELSEVIER SCIENCE}, address = {525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA}, abstract = {

The effect of incorporating carbon nanotubes (CNTs) in the gel matrix on the electrophoretic mobility of proteins based on their molecular weight differences was investigated using sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). More specifically, a reduction in standard deviation in the molecular weight calibration plots by 55\% in the case of multiwalled carbon nanotubes (MWCNTs) and by 34\% in the case of single-walled carbon nanotubes (SWCNTs) compared with that of pristine polyacrylamide gels was achieved after incorporating an insignificant amount of functionalized CNTs into the gel matrix. A mechanism based on a more uniform pore size distribution in CNT modified polyacrylamide gel matrix is proposed. Furthermore, the impact of SWCNTs and MWCNTs on the mobility of proteins in different molecular weight regimes at a given acrylamide concentration offers a tunable gel matrix in terms of the selection of molecular weight ranges of proteins. The robustness and excellent reproducibility of the CNT-PAGE protocol are expected to have a significant impact on the molecular weight determination of newly isolated proteins. (C) 2010 Elsevier Inc. All rights reserved.

}, keywords = {Carbon nanotubes, Gel electrophoresis, Molecular weight determination, Polyacrylamide, Protein separation}, issn = {0003-2697}, doi = {10.1016/j.ab.2010.10.021}, author = {Parthasarathy, Meera and Debgupta, Joyashish and Kakade, Bhalchandra A. and Ansary, Abu Ayoobul and Khan, Mohammad Islam and Pillai, Vijayamohanan K.} } @article { ISI:000293516200047, title = {Competitive wetting of acetonitrile and dichloromethane in comparison to that of water on functionalized carbon nanotube surfaces}, journal = {Physical Chemistry Chemical Physics}, volume = {13}, number = {32}, year = {2011}, month = {JUL}, pages = {14668-14674}, publisher = {ROYAL SOC CHEMISTRY}, address = {THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLAND}, abstract = {

Differential wetting of pristine and ozonized carbon nanotubes has been studied using solvents like acetonitrile and dichloromethane in comparison to the well-known wetting behavior of water. Based on their unique structural and physical properties, functionalized CNT substrates have been used due to the fact that independent variation in molecular as well as electronic properties could be controlled by understanding the wetting of these liquids on carbon nanotubes (CNTs), both pristine as well as ozone treated. The sensitivity of the wetting behavior with respect to molecular interactions has been investigated using contact angle measurements while Raman and XPS studies unravel the differential wetting behavior. Charge-transfer between adsorbed molecules and CNTs has been identified to play a crucial role in determining the interfacial energies of these two liquids, especially in the case of acetonitrile. Ozone treatment has been observed to affect the surface properties of pristine CNTs along with a concomitant change in the wetting dynamics.

}, issn = {1463-9076}, doi = {10.1039/c1cp21121h}, author = {Debgupta, Joyashish and Kakade, Bhalchandra A. and Pillai, Vijayamohanan K.} } @article {43020, title = {Nitrogen doping in oxygen-deficient Ca2Fe2O5: a strategy for efficient oxygen reduction oxide catalysts}, journal = {ACS Applied Materials and Interfaces}, volume = {8}, year = {2016}, month = {NOV}, pages = {34387{\textendash}34395}, doi = {10.1021/acsami.6b11718}, author = {Jijil, Chamundi P. and Lokanathan, Moorthi and Chithiravel, Sundaresan and Nayak, Chandrani and Bhattacharyya, Dibyendu and Jha, Shambhu Nath and Babu, P. D. and Kakade, Bhalchandra A. and Devi, R. Nandini} }