• Bulletin of the Korean Chemical Society
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• v.35 no.6
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• pp.1647-1653
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• 2014

9,10-Bis(bromomethyl)phenanthrene reacted with fullerenes via a Diels-Alder reaction to give phenanthrene-substituted fullerene mono-adducts (PCMA) and bis-adducts (PCBA) as electron acceptors for organic photovoltaic cells (OPVs). The syntheses of the fullerene derivatives were confirmed by $^1H$ $^{13}C$ NMR spectroscopy and MALDI-TOF mass spectrometry. PCMA and PCBA showed better light absorption in the UV-visible region than $PC_{61}BM$. Their electrochemical properties were measured using cyclic voltammetry. Accordingly, the lowest unoccupied molecular orbital (LUMO) energy levels of PCMA and PCBA were -3.66 and -3.57 eV, respectively. Photovoltaic cells were fabricated with a ITO/PEDOT:PSS/poly(3-hexylthiophene)(P3HT):acceptor/LiF/Al configuration, where P3HT and PCBA are the electron donors and acceptors, respectively. The polymer solar cell fabricated using the P3HT:PCBA active layer showed a maximum power conversion efficiency of 0.71%.

• Journal of the Korean Applied Science and Technology
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• v.31 no.1
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• pp.50-58
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• 2014

A novel fullerene derivative with photoresponsive azobenzene group was designed and synthesized, and its photoresponsive properties were reported. Starting from 4-nitrophenol, compound 1, which is containing fullerene moiety connected to azobenzene group through covalent linkage was synthesized by 5 steps. All the intermediates and the final compound were characterized by $^1H$, $^{13}C$-NMR, FAB-Mass or elemental analysis. Compound 1 exhibited the expected photoresponsive behavior. Chloroform solution($10^{-5}M$) of it served to maximize the absorption at 351 nm corresponding to the trans-azobenzene chromophore. Irradiation of this solution with 365 nm light resulted in photoisomerization to cis-azobenzene, as evidenced by decrease in the absorbance at 351 nm and an increase in absorbance at 450nm. A photostationary state was reached within about 150 s. Thermal reversion to the original spectrum was observed over the course of about 6 h at room temperature in the dark. However, exposure to bright sun light for about 5 s also effect almost complete reversion to the trans-isomer. This indicates that there is no strong steric influence on the trans-cis reversible isomerization of compound 1.

• Coupled systems mechanics
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• v.3 no.4
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• pp.329-344
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• 2014

In this work, quantum molecular dynamics simulations (QMD) are preformed to study the hydrogen molecules in three types of carbon nanostructures, $C_{60}$ fullerene, (5,5) and (9,0) carbon nanotubes and graphene layers. Interactions between hydrogen and the nanostructures is of importance to understand hydrogen storage for the development of hydrogen economy. The QMD method overcomes the difficulties with empirical interatomic potentials to model the interaction among hydrogen and carbon atoms in the confined geometry. In QMD, the interatomic forces are calculated by solving the Schrodinger's equation with the density functional theory (DFT) formulation, and the positions of the atomic nucleus are calculated with the Newton's second law in accordance with the Born-Oppenheimer approximation. It is found that the number of hydrogen atoms that is less than 58 can be stored in the $C_{60}$ fullerene. With larger carbon fullerenes, more hydrogen may be stored. For hydrogen molecules passing though the fullerene, a particular orientation is required to obtain least energy barrier. For carbon nanotubes and graphene, adsorption may adhere hydrogen atoms to carbon atoms. In addition, hydrogen molecules can also be stored inside the nanotubes or between the adjacent layers in graphite, multi-layer graphene.

• Elastomers and Composites
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• v.43 no.4
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• pp.264-270
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• 2008

$\alpha$-D-mannosyl fullerene[$C_{60}$]-functionalized gold nanoparticle films were selfassembled using the layer-by-layer method on the reactive of glass slides functionlized with 3-aminopropyltrimethoxysilane. The functionalized glass slides were alternately soaked in the solutions containing $\alpha$-D-mannosyl fullerene[$C_{60}$] and 4-aminothiophenoxide/hexanethiolate-protected gold nanoparticles. $\alpha$-D-mannosyl fullerene[$C_{60}$]-functionalized gold nanoparticle films have grown up to 5 layers depending on the immersion time. The self-assembled nanoparticle films were characterized using UV-vis spectroscopy showed that the surface plasmon band of gold at 530 nm gradually became more evident as successive layers were added to the films.

• 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.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2009.04a
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• pp.57-58
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• 2009

The dynamics of nano or micro sized-particles in liquid crystal (LC) medium under an external electric field is of theoretical and technological interest. A fullerene of 10 wt% was doped into the LC medium and its electric field induced motion was controlled by both in-plane and vertical electric fields. In the proposed device, pixel electrode I and pixel electrode II were designed consecutively on the bottom substrate and common electrode on the top of the substrate. When the electric field was applied, the fullerenes start to move in direction of applied electric field. The dark, grey and white states in the proposed device can be obtained by suitable combination of the polarity of applied electric field at pixel electrode I, pixel electrode II and common electrode. The dynamical motions of fullerene particles in LC medium suggest that fullerene can be designed for electronic-paper like displays.

• Analytical Science and Technology
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• v.6 no.2
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• pp.149-156
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• 1993

The formation of the graphite spherulites has been studied experimentally in the Ni-C liquid under high pressure and temperature. In the diamond-stable region the graphite spherulites were formed and grew stably. They were not the polycrystalline particles but the single crystals of the fullerene-type, respectively, grown spirally with much imperfection. And they were proved to be in a mixture state of carbon atoms with $sp^2$- and $sp^3$-bonding by an Auger electron spectroscope and a high resolution transmission electron microscope. As the pressure decreased from the diamond-stable region to the graphite-stable region, the shape of the graphite particles changed gradually from the sphere to the flaky shape. The formation of the graphite spherulites was attributed to the stable existence of the carbon atoms with $sp^3$ bonding in the diamond-stable region. The formation of the large fullerene-type graphite spherulites with much imperfection is well agreed with Kroto's prediction for growth of the giant fullerene.

• Elastomers and Composites
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• v.40 no.3
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• pp.174-180
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• 2005

Sonochemical synthesis of fullerene oxides $[C_{70}O_n](n=1{\sim}2)$ by fullerene$[C_{70}]$ and metal hexacarbonyl complexes $M(CO)_6$(M=Cr, Mo, W) took place under air atmosphere. The reactivity of fullerene$[C_{70}]$ and several metal hexacarbonyl complexes $M(CO)_6$(M=Cr, Mo, W) under same ultrasonic condition increased in the order of $Mo(CO)_6$ > $W(CO)_6$ > $Cr(CO)_6$. The MALDI-TOF-MS, UV-visible spectra, and HPLC analysis confirmed that the products of sonochemical reaction were $[C_{70}O_n](n=1{\sim}2)$.

• Journal of the Korean Electrochemical Society
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• v.7 no.1
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• pp.16-20
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• 2004

To electropolymerize Polypyrrole(ppy) film modified with fullerene $ions(full^-)$ the cell, Au/5 mM pyrrole, 1mM fullerene, 0.1M $TBABF_4,\;CH_2Cl_2/Pt$, was employed to Prepare the wafer-like type of $electrode/ppy(full^-)ppy(full^-){\ldots}$ electrodes. They were applied to deposit alkali metal ions with the cell of Au(quartz crystal analyzer; QCA)/ppy$(full^-)$, 0.01M metal ion(aq.)/Pt. The depositing rate constant of each ion for $Li^+,\;Na^+,\;K^+,\;Rb^+\;and\;Cs^+$, determined from the first order equation was $1.60\times10^{-8},\;3.13\times10^{-11},\;1.38\times10^{-9},\;2.71\times10^{-11}\;and\;2.98\times10^{-12}mo1.s^{-1}$ respectively. The calculated stoichiometry of the ions determined by quartz crystal microbalance(QCM) at the electrodes was $Li_7C_{60},\;Na_4C_{60},\;K_3C_{60},\;Rb_1C_{60}\;and\;Cs_1C_{60}$ respectively.

• Journal of electromagnetic engineering and science
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• v.14 no.3
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• pp.267-272
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• 2014

Hyperthermia is a form of cancer treatment in which affected human tissue is exposed to $>40^{\circ}C$ temperature. In this paper, our goal is to assess the efficacy of fullerene agents to reduce heating time for cancer treatment. Such agents can accelerate heating of cancer cells and improve hyperthermia treatment efficacy. Typically, in vitro testing involves cancer cell culturing, heating cell cultures in accordance to specifications, and recording cancer cell viability after hyperthermia. To heat cell cultures, we design and evaluate a 2.4-GHz microwave cavity with controllable temperature. The cavity is comprised of a polystyrene cell culture dish (diameter = 54 mm, height = 13.5 mm) and a printed monopole antenna placed within the cavity for microwave heating. The culture temperature can be controlled through the intensity and duration of the antenna's microwave radiation. Heating experiments were carried out to validate the cavity's performance for F-12K culture medium (Kaighn's F-12K medium, ATCC). Importantly, fullerene agents were shown to reduce heating time and improve hyperthermia treatment efficacy. The culture medium temperature increased, on average, from $24.0^{\circ}C$ to $50.9^{\circ}C$ (without fullerene) and from $24.0^{\circ}C$ to $56.8^{\circ}C$ (with 3 mg/mL fullerene) within 15 minutes.