• Journal of Photoscience
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• v.10 no.1
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• pp.105-119
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• 2003

Fullerenes, $C_{60}$ and $C_{70}$, display interesting physicochemical properties in solutions, especially due to their unique chemical structures and their good electron accepting abilities. Solubility of fullerenes in different organic solvents and their unusual solvatochromic behavior, the ability of the fullerenes to form aggregates in solutions, and their electron transfer and charge transfer interactions with variety of electron donors, are the subjects of extensive research activities for more than one decade. Many research groups including ours have contributed substantially in the understanding of the solvatochromism, aggregation behavior, and the photoinduced electron transfer and charge transfer chemistry of fullerenes, in condensed phase. Present article is aimed to summarize the important results reported on the above aspects of fullerenes, subsequent to the earlier report from our group (D.K. Palit and J.P. Mittal, Full. Sci. & Tech. 3, 1995, 643-659).)., 643-659)..

• Composites Research
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• v.26 no.2
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• pp.111-115
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• 2013

Aluminum-based composites containing $C_{60}$-fullerenes are produced by hot rolling of ball-milled powder. The grain size of aluminum is effectively reduced to ~100 nm during ball-milling processes, leading to grain refinement strengthening of the composite. Furthermore, $C_{60}$-fullerenes are gradually dispersed during ball-milling processes and hence the strength of the composite increases with the volume of $C_{60}$-fullerenes. The composite containing 10 vol% $C_{60}$-fullerenes with a grain size of ~ 100 nm exhibits ~1 GPa of compressive strength.

• Journal of the Korean Chemical Society
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• v.40 no.7
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• pp.515-518
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• 1996

Functional conversion of polybrominated fullerenes has been discussed. These reactions are Friedel-Crafts fullerylation of aromatics, methoxylation and phosphorylation of polybrominated fullerenes.

• Bulletin of the Korean Chemical Society
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• v.33 no.8
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• pp.2703-2706
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• 2012

New C60 fullerenes derivatives [G1]-C60 (1) and [G2]-C60 (2) comprising of phenylenevinylene bridges and phenylquinoline peripheral surface groups were synthesized by 1,3-dipolar cycloaddition reaction of fullerene C60 with azomethine ylide in situ generated from [Gx]-CHO dendrons (x = 1 and 2) and sarcosine.

• Journal of the Korean Society of Combustion
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• v.7 no.4
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• pp.36-44
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• 2002

Carbon molecules with closed-cage structures are called fullerenes $(C_{60},\;C_{70})$, whose applications include super-conductors, sensors, catalysts, optical and electronic device, polymer composites, and biological and medical materials. The synthesis of fullerenes has been recently studied with low-pressure benzene/argon/oxygen flames. The formation of fullerene is known as molecular weight growth processes of PAHs (polycyclic aromatic hydrocarbon). This study presents results of PAHs and fullerene measurements performed in a low-pressure benzene/argon/oxygen normal co-flow laminar diffusion flame. Through the central tube of the burner, benzene vapors carried by argon are injected. The benzene vapors are made in a temperature-controlled bubbler. The burner is located in a chamber, equipped with a sampling system for direct collection of condensable species from the flame, and exhausted to a vacuum pump. Samples of the condensable are analyzed by HPLC (High Performance Liquid Chromatography) to determine the yields of PAHs and fullerene. Also, we computed mole fraction of fullerene and PAHs in a nearly sooting low pressure premixed, one-dimensional benzene/argon/oxygen flame (equivalence ratio ${\Phi}=2.4$, pressure=5.33kPa). The object of computation was to investigate the formation mechanism of fullerenes and PAHs. The computations were performed with CHEMKIN/PREMIX. As a result of this study, fullerenes were synthesized in a low pressure (20torr) $C_6H_6/Ar/O_2$ flames and the highest concentration of fullerene was detected just above the visible surface of a flame.

• Elastomers and Composites
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• v.38 no.2
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• pp.147-156
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• 2003

Synthesis of fullerene oxides by fullerenes [$C_{60},\;C_{70}$] and several oxidants such as benzoylperoxide, trichloroisocyanuric acid, methyltrioxorhenium(VII), iodosobenzene, phosphorous pentoxide take place under ultrasonic condition at room temperature. The MALDI-TOF MS,UV-visible spectra and HPLC analysis confirmed that the products of fullerenes oxidation are [$C_{60}(O)_n$], ($n=1{\sim}3$ or n=1) and [$C_{70}(O)_n$], ($n=1{\sim}2$ or n=1). As compared with the reactivity of epoxidation of fullerenes [$C_{60},\;C_{70}$], the reaction rate of $C_{70}$ was lower than that of $C_{60}$ under same reaction condition.

• Transactions on Electrical and Electronic Materials
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• v.5 no.6
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• pp.227-232
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• 2004

We investigated a nonvolatile nanomemory element based on boron nitride nanopeapods using molecular dynamics simulations. The studied system was composed of two boron-nitride nanotubes filled Cu electrodes and fully ionized endo-fullerenes. The two boron-nitride nanotubes were placed face to face and the endo-fullerenes came and went between the two boron-nitride nanotubes under alternatively applied force fields. Since the endo-fullerenes encapsulated in the boron-nitride nanotubes hardly escape from the boron-nitride nanotubes, the studied system can be considered to be a nonvolatile memory device. The minimum potential energies of the memory element were found near the fullerenes attached copper electrodes and the activation energy barrier was $3{\cdot}579 eV$. Several switching processes were investigated for external force fields using molecular dynamics simulations. The bit flips were achieved from the external force field of above $3.579 eV/{\AA}$.

• Proceedings of the Korean Society of Dyers and Finishers Conference
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• 2008.04a
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• pp.77-79
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• 2008

Polynitro fullerenes were synthesized by reaction C-60 in benzen solution with a mixture of NaNO$_2$ and HNO$_3$. Hydrolysis of polynitro fullerenes in aqueous NaOH gave the corresponding polyhydroxylated fullerenes. Sulfonation reaction was carried out in pyridine solution of ClSO$_3$H. Infrared spectra of the resultant fullerene derivatives showed the characteristic IR bands, corresponding to absorptions of O-H, N-O, and SO$_3$Na functions. Electric resistivity and thermal transmittance of wool fiber absorbed with the water-soluble C-60 were investigated. Thermal transmittances of wool fiber were increased with increasing water-soluble C-60 concentrations, but electric conductivity were decreased with raising water-soluble C-60 uptake values.

• Bulletin of the Korean Chemical Society
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• v.24 no.6
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• pp.797-801
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• 2003

One of the largest challenges for quantum chemistry today is to obtain accurate results for large complex molecular systems, and a variety of approaches have been proposed recently toward this goal. We have developed the ONIOM method, an onion skin-like multi-level method, combining different levels of quantum chemical methods as well as molecular mechanics method. We have been applying the method to many different large systems, including thermochemistry, homogeneous catalysis, stereoselectivity in organic synthesis, solution chemistry, fullerenes and nanochemistry, and biomolecular systems. The method has recently been combined with the polarizable continuum model (ONIOM-PCM), and was also extended for molecular dynamics simulation of solution (ONIOM-XS). In the present article the recent progress in various applications of ONIOM and other electronic structure methods to problems of homogeneous catalyses and nanochemistry is reviewed. Topics include 1. bond energies in large molecular systems, 2. organometallic reactions and homogeneous catalysis, 3. structure, reactivity and bond energies of large organic molecules including fullerenes and nanotubes, and 4. biomolecular structure and enzymatic reaction mechanisms.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.21 no.2
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• pp.118-125
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• 2008

Single walled carbon nanotubes (SWCNTs) can be modified to produce a new concept of hybrid materials by introducing atoms or molecules inside their cylindrical empty space. Such an endohedral doping of the SWCNTs is expected to decisively alter their electronic transport and mechanical properties, In this study, we purified SWCNTs by three-step purification processes and formed the peapod structure by introducing $C_{60}$ fullerenes inside the SWCNTs. $C_{60}$ molecules were observed to be regularly arranged by transmission electron microscopy. In Raman spectra, the radial breathing mode (RBM) rather than the other modes was significantly affected by the endohedral injection of $C_{60}$. The RBM intensity was more greatly reduced in the large-diameter SWCNTs than the small-diameter ones, Raman spectroscopy is expected to be a key technique for analyzing $C_{60}$-encapsulated SWCNTs.