@article { ISI:000252413800017, title = {Copolyester nanocomposites based on carbon nanotubes: reinforcement effect of carbon nanotubes on viscoelastic and dielectric properties of nanocomposites}, journal = {Polymer International}, volume = {57}, number = {1}, year = {2008}, month = {JAN}, pages = {114-123}, publisher = {WILEY-BLACKWELL}, type = {Article}, address = {111 RIVER ST, HOBOKEN 07030-5774, NJ USA}, abstract = {

Nanocomposites based on an amorphous copolyester, poly(ethylene glycol-co-cyclohexane-1,4-dimethanol terephthalate) and carbon nanotubes were fabricated using a simple melt processing technique. The reinforcement effect of carbon nanotubes in the copolyester was investigated experimentally using different approaches based on dynamic mechanical analysis, theology and dielectric analysis. The nanocomposites show a mechanical reinforcement effect with significant increase in the stiffness especially in the rubbery regime with increasing nanotube content. An increase in T-g and a decrease in damping are seen, which are derived from the presence of a percolating superstructure of the filler. Rheological experiments show an increase in storage modulus up to four orders of magnitude. Viscolelastic characterization shows that the percolation threshold is at 3 wt\% of nanotubes. Dielectric relaxation spectroscopy confirms the presence of this percolating structure. We conclude that the responses of both rheological and electrical properties are different, although both are related to the formation of a percolating network superstructure of the filler. (c) 2007 Society of Chemical Industry.

}, keywords = {Carbon nanotubes, dielectric analysis, nanocomposites., reinforcement, viscoelastic properties}, issn = {0959-8103}, doi = {10.1002/pi.2325}, author = {Kalgaonkar, Rajendra A. and Jog, Jyoti Prakash} } @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:000260776600007, title = {Functionalization of single-walled carbon nanotubes with azides derived from amino acids using click chemistry}, journal = {Journal of Nanoscience and Nanotechnology}, volume = {8}, number = {7}, year = {2008}, month = {JUL}, pages = {3351-3356}, publisher = {AMER SCIENTIFIC PUBLISHERS}, type = {Article}, address = {25650 NORTH LEWIS WAY, STEVENSON RANCH, CA 91381-1439 USA}, abstract = {

Single-walled carbon nanotubes (SWCNTs) were chemically functionalized with amino acid-based moieties. The covalent functionalization of alkyne-derived SWCNTs with well defined azides derived from amino acids was accomplished through Cu(I)-catalyzed Huisgen [3+2] dipolar cycloaddition click chemistry. Transmission electron microscopy, Raman spectroscopy, and infrared spectroscopic measurements confirmed the functionalization of SWCNTs by organic molecules derived from amino acids, and the resulting material showed some good solubility in the organic solvents such as tetrahydrofuran, CH2Cl2, and CHCl3.

}, keywords = {Amino acids, Carbon nanotubes, Click chemistry, Functionalization}, issn = {1533-4880}, doi = {10.1166/jnn.2008.109}, author = {Kumar, Indresh and Rana, Sravendra and Rode, Chandrashakher V. and Cho, Jae Whan} } @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:000265186800069, title = {Assembly of gold nanoparticles on single-walled carbon nanotubes by using click chemistry}, journal = {Journal of Nanoscience and Nanotechnology}, volume = {9}, number = {5}, year = {2009}, month = {MAY}, pages = {3261-3263}, publisher = {AMER SCIENTIFIC PUBLISHERS}, address = {25650 NORTH LEWIS WAY, STEVENSON RANCH, CA 91381-1439 USA}, abstract = {

Azide moiety-functionalized gold nanoparticles were conjugated with acetylene functionalized single-walled carbon nanotubes by employing copper-catalyzed Huisgen{\textquoteright}s [3+2] dipolar cycloaddition {\textquoteleft}click chemistry{\textquoteright} reaction. Evidences of conjunction were observed by TEM, EDX and Raman images.

}, keywords = {Carbon nanotubes, Click chemistry, Functionalization, Nanoparticles}, issn = {1533-4880}, doi = {10.1166/jnn.2009.035}, author = {Rana, Sravendra and Kumar, Indresh and Yoo, Hye Jin and Cho, Jae Whan} } @article { ISI:000270363600029, title = {Enhanced conversion efficiency in dye-sensitized solar cells based on hydrothermally synthesized TiO2-MWCNT nanocomposites}, journal = {ACS Applied Materials \& Interfaces}, volume = {1}, number = {9}, year = {2009}, month = {SEP}, pages = {2030-2035}, publisher = {AMER CHEMICAL SOC}, address = {1155 16TH ST, NW, WASHINGTON, DC 20036 USA}, abstract = {

A 50 \% enhancement in the conversion efficiency (4.9-7.37 \%) is realized in dye-sensitized solar cells Using hydrothermally synthesized TiO2-multiwalled carbon nanotube (MWCNT) nanocomposites as compared to hydrothermally synthesized TiO2 without MWCNT and Degussa P25. Several characterizations have been employed to reveal the nature of the modification imparted to the MWCNTs under hydrothermal processing conditions and the resulting TiO2-MWCNT conjugation through -COOH groups. Efficient charge transfer In the nanocomposite and efficient electron transport by MWCNT (significantly higher Incident-photon-to-current conversion efficiency) are suggested to be the possible reasons for the enhancement.

}, keywords = {Carbon nanotubes, charge transfer, Dye-sensitized solar cells, Hybrid composite, hydrothermal}, issn = {1944-8244}, doi = {10.1021/am900396m}, author = {Muduli, Subas and Lee, Wonjoo and Dhas, Vivek V. and Mujawar, Sarfraj and Dubey, Megha and Vijayamohanan, K. and Han, Sung-Hwan and Ogale, Satishchandra} } @article { ISI:000266529600001, title = {Nanoscale particles for polymer degradation and stabilization-trends and future perspectives}, journal = {Progress in Polymer Science}, volume = {34}, number = {6}, year = {2009}, month = {JUN}, pages = {479-515}, publisher = {PERGAMON-ELSEVIER SCIENCE LTD}, address = {THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND}, abstract = {

The field of nanoscience and nanotechnology is extending the applications of physics, chemistry, biology, engineering and technology into previously unapproached infinitesimal length scales. The polymer-nanoparticles/nanocomposites have been the exponentially growing field of research for developing the materials in last few decades and have been mainly focusing on the structure-property relationships and their development. Since the polymer-nanocomposites have been the staple of modern polymer industry, their durability under various environmental conditions and degradability after their service life are also essential fields of research. Thus, this article is intended to review the status of worldwide research in this aspect. Among various nanoparticulates, clay minerals and carbon nanotubes are more often used in enhancing physical, mechanical and thermal properties of polymers. In very few systems, the nano particulates have been incorporated into polymer as {\textquoteleft}nano-additives{\textquoteright} for both purposes: degradation and stabilization of polymers. The degradation and durability of polymers is reviewed in the presence of nanoparticles/nanocomposites under different environmental conditions. Nanoparticle-induced biodegradation of polymers is also discussed. (c) 2009 Elsevier Ltd. All rights reserved.

}, keywords = {Carbon nanotubes, clay, Degradation and stabilization, Nanocomposites, Nanoparticles, Polymer}, issn = {0079-6700}, doi = {10.1016/j.progpolymsci.2009.01.002}, author = {Kumar, Annamalai Pratheep and Depan, Dilip and Tomer, Namrata Singh and Singh, Raj Pal} } @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:000275755500010, title = {Monitoring structural defects and crystallinity of carbon nanotubes in thin films}, journal = {Pramana-Journal of Physics}, volume = {74}, number = {3}, year = {2010}, month = {MAR}, pages = {447-455}, publisher = {INDIAN ACAD SCIENCES}, address = {C V RAMAN AVENUE, SADASHIVANAGAR, P B \#8005, BANGALORE 560 080, INDIA}, abstract = {

We report the influence of catalyst formulation and reaction temperature on the formation of carbon nanotube (CNT) thin films by the chemical vapour deposition (CVD) method. Thin films of CNTs were grown on Fe-Mo/Al(2)O(3)-coated silicon wafer by thermal decomposition of methane at different temperatures ranging from 800 to 1000A degrees C. The electron microscopic investigations, SEM as well as HRTEM, of the as-grown CNT thin films revealed the growth of uniform multi-walled CNTs in abundance. The intensity ratio of D-band to G-band and FWHM of G-band through Raman measurements clearly indicated the dependency of structural defects and crystallinity of CNTs in thin films on the catalyst formulation and CVD growth temperature. The results suggest that thin films of multi-walled CNTs with negligible amount of defects in the nanotube structure and very high crystallinity can be obtained by thermal CVD process at 925A degrees C.

}, keywords = {Carbon nanotubes, chemical vapour deposition, Raman spectroscopy, scanning electron microscopy, Thin films}, issn = {0304-4289}, doi = {10.1007/s12043-010-0040-9}, author = {Mahajan, S. S. and Bambole, M. D. and Gokhale, S. P. and Gaikwad, A. B.} } @article { ISI:000279836400026, title = {Synthesis and characterization of polyurethane-grafted single-walled carbon nanotubes via click chemistry}, journal = {Journal of Nanoscience and Nanotechnology}, volume = {10}, number = {9}, year = {2010}, month = {SEP}, pages = {5700-5707}, publisher = {AMER SCIENTIFIC PUBLISHERS}, address = {26650 THE OLD RD, STE 208, VALENCIA, CA 91381-0751 USA}, abstract = {

Polyurethane (PU)-grafted carbon nanotubes were synthesized by the coupling of alkyne moiety decorated single walled carbon nanotube (SWCNT) with azide moiety containing PU using Cu(I) catalyzed Huisgen [3 + 2] cycloaddition click chemistry. The azide moiety containing poly(E-caprolactone)diol was synthesized by ring-opening polymerization and further used for PU synthesis. Alkyne-functionalizion of SWCNT was completed by the reaction of p-aminophenyl propargyl ether with SWCNT using a solvent free diazotization procedure. Nuclear magnetic resonance, Fourier transform infrared, and Raman spectroscopic measurements confirmed the functionalization of SWCNT. Scanning electron microscopy and transmission electron microscopy images showed an excellent dispersion of SWCNTs, and specially debundling of SWCNTs could be observed due to polymer assisted dispersion. A quantitative grafting was successfully achieved even at high content of functional groups.

}, keywords = {Carbon nanotubes, Click chemistry, dispersion, polyurethane}, issn = {1533-4880}, doi = {10.1166/jnn.2010.2434}, author = {Rana, Sravendra and Cho, Jae Whan and Kumar, Indresh} } @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 {45723, title = {Single cell fabrication towards the realistic evaluation of a CNT-strung ZIF-derived electrocatalyst as a cathode material in alkaline fuel cells and metal-air batteries}, journal = {ChemElectroChem}, volume = {4}, year = {2017}, month = {NOV}, pages = {2928-2933}, type = {Article}, abstract = {

The development of an electrocatalyst possessing all the vital requisites of an ideal electrode material, such as high porosity, high conductivity, and high intrinsic electrochemical activity, holds a decisive key in determining the activity of the triplephase boundary in many energy devices like fuel cells and metal-air battery systems. In the present work, highly porous cobalt-based ZIFs are strung along the highly conducive CNT backbone by using a simple one-pot technique at room temperature, which is then utilized to derive a porous, corrosion-resistant, Co nanoparticle-embedded electrocatalyst. Herein, for the first time, the single cell performance of the Co-ZIF-67-derived electrocatalyst has been evaluated by fabricating membrane electrode assemblies of alkaline exchange membrane fuel cell (AEMFC) and zinc-air battery (ZAB) systems. A maximum power density of 296 mW/cm(2) (vs. 317 mW/cm(2) for 40 wt.\% Pt/C) and 60 mW/cm(2) (vs. 64 mW/cm(2) for 40 wt.\% Pt/C) in the single cells of ZAB and AEMFC systems, respectively, establishes the practical proficiency of the homemade electrocatalyst for cathode applications during realistic system-level validations.

}, keywords = {Batteries, Carbon nanotubes, Composite materials, fuel cells, metal-organic frameworks}, issn = {2196-0216}, doi = {10.1002/celc.201700562}, author = {Aiyappa, Harshitha Barike and Bhange, Siddheshwar N. and Sivasankaran, Vijitha P. and Kurungot, Sreekumar} } @article {43975, title = {Ultrananocrystalline diamond decoration on to the single wall carbon nano tubes}, journal = {Applied Surface Science}, volume = { 418}, year = {2017}, month = {OCT}, pages = {401-405}, type = {Journal Article}, abstract = {

We have demonstrated the decoration of the ultrananocrystalline diamonds on single walled carbon nanotubes using a hot filament assisted chemical vapor deposition. Study reveals the critical influence of the filament to substrate distance on the formation of ultrananocrystalline diamonds on to the single walled carbon nanotubes. It is also observed that etching of carbon nanotubes, due to the presence of unavoidable atomic hydrogen throughout the chemical vapor deposition processes, can be significantly reduced by adjusting the filament to substrate distance. Morphological and structural investigations performed using high resolution transmission electron microscope suggests the growth of ultrananocrystalline diamond is subsequent to the formation of crystalline sp2 carbon layer on the nanotube wall, enabling us to suggest a growth model. The composite synthesized can be thought not only to use as a fuel cell catalyst support but also as chemical sensors, bio-sensors and micro electromechanical systems (MEMS).

}, keywords = {Carbon nanotubes, Composite Coating, Electron microscopy (STEM, Nanostructures, TEM and SEM)}, doi = { 10.1016/j.apsusc.2016.12.057}, author = {Sinha, B. and Late, D. and Jejurikar, S.M.} } @article {46040, title = {Graphene nanosheets assisted carbon hollow cylinder for high-performance field emission applications}, journal = {Materials Research Express}, volume = {6}, year = {2019}, month = {SEP}, pages = {095066}, type = {Article}, abstract = {

Electron sources are critical constituents for myriad many electronic applications including electron imaging, mass spectroscopy etc. Here, we report the realization of high-performance field emission from graphene assisted carbon hollow cylinders (Gr-CHCs) composed of multi-stacked radially aligned CNTs. These CHCs have built-in synthesis related Fe nanoparticles (NPs). This engineered nano-structure exhibits excellent field emission properties such as one of the ultra-low turn-on field (0.64V mu m(-1) at 10 mu A cm(-2)), low threshold field (0.74V mu m(-1) at 100 mu A cm(-2)), very high current density (15.49 mA cm(-2) at 1.32V mu m(-1)) which is nearly double the current density obtained in our previous study. High field enhancement factor (0.72. x. 10(4)) with highly stable emission current at 100 mu A was observed for more than 3 hrs at the base pressure of similar to 1. x. 10(-8) mbar. This study suggests an approach to enhance the current density using the proposed innovative nanostructure and forms the basic theme of this communication. Highly efficient and stable field emissions observed are attributed to the geometry of cylinder and the production of the high density of sharp protrusions within the graphene sheets which enhance the local electric field and dramatically enhance field emission. This innovative cylindrical geometry associated with graphene assisted on Fe bearing aligned CNTs along with the periphery of the bulk cylinder provides an easy injection of electrons from the conduction band of CHCs into the vacuum in the presence of an external electric field. The tunability of field emission properties of these CHCs can be easily achieved by tailoring their diameter (10 and 20 mm) and different concentrations of the precursor. This new approach of the graphene assisted cylindrical geometry-based field emitter source provides enormous prospects and demand for next-generation high resolutions display devices.

}, keywords = {Carbon nanotubes, field emission, graphene assisted carbon hollow cylinder, protrusions}, issn = {2053-1591}, doi = {10.1088/2053-1591/ab3030}, author = {Tripathi, Prashant and Gupta, Bipin Kumar and Bankar, Prashant K. and More, Mahendra A. and Late, Dattatray J. and Srivastava, Onkar Nath} }