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111.
CHEN Jian-xin SHENG Guo-ying LIU Shu-ying LIU Zi-yang LIU Zhi-qiang FU Jia-mo ZHANG Xiao-mei 《高等学校化学研究》1999,15(1):90-93
IntroductionAfascinatingsolidblackcondensate(herecaledfulerenesoot)isgeneratedinthegasphaseanddepositedduringthedischargeinaK... 相似文献
112.
Naotoshi Nakashima Takeshi Tokunaga Yuko Nonaka Takashi Nakanishi Hiroto Murakami Takamasa Sagara 《Angewandte Chemie (International ed. in English)》1998,37(19):2671-2673
Two reversible one-electron transfers are observed for an electrode device made from C60 and an artificial lipid (see schematic drawing). Cyclic voltammetric studies reveal that the redox couples are unchanged even after 50 cycles, thus indicating that the C60 radical monoanion and the C60 dianion generated in aqueous solution are very stable. 相似文献
113.
S. Wehrli D. Poilblanc T.M. Rice 《The European Physical Journal B - Condensed Matter and Complex Systems》2001,23(3):345-350
We study the charge profile of a C60-FET (field effect transistor) as used in the experiments of Sch?n, Kloc and Batlogg. Using a tight-binding model, we calculate
the charge profile treating the Coulomb interaction in a mean-field approximation. At low doping, the charge profile behaves
similarly to the case of a continuous space-charge layer and becomes confined to a single interface layer for doping higher
than ∼
0.3 electron (or hole) per C60 molecule. The morahedral disorder of the C60 molecules smoothens the structure in the density of states.
Received 21 June 2001 相似文献
114.
Harold W. Kroto 《Angewandte Chemie (International ed. in English)》1992,31(2):111-129
In 1975–1978 the long-chained polyynylcyanides, HC5N, HC7N, and HC9N were surprisingly discovered in the cold dark clouds of interstellar space by radioastronomy. The subsequent quest for their source indicated that they were being blown out of red giant, carbon stars. In 1985 carbon-cluster experiments aimed at simulating the chemistry in such stars confirmed these objects as likely sources. During these cluster studies a serendipitous discovery was made; a stable pure-carbon species, C60, formed spontaneously in a chaotic plasma produced by a laser focused on a graphite target. A closed spheroidal cage structure was proposed for this molecule, which was to become the third well-characterized allotrope of carbon and was named buckminsterfullerene. It has taken five years to produce sufficient material to prove the correctness of this conjecture. There may be a timely object lesson in the fact that exciting new and strategically important fields of chemistry and materials science have been discovered overnight due to fundamental research, much of which was unable to attract financial support, and all of which was stimulated by a fascination with the role of carbon in space and stars. In this account, interesting aspects of this discovery, its origins, and its sequel are presented. The story has many facets, some of which relate to the way scientific discoveries are made. 相似文献
115.
XUE Zhixin YANG Guipeng CHEN Dianbao MA Xiaomei ZHANG Xiqin QUAN Zhenlan College of Chemical Engineering Environment Qingdao University Qingdao China Key Laboratory of Marine Chemistry Theory Technology Ministry of Education Ocean University of China Qingdao P.R.China Fullerenes Materials Group Qingdao University of Science Technology Qingdao China 《Chinese Journal of Reactive Polymers》2006,(1)
1. INTRODUCTION1. INTRODUCTIONOne of the most widely discussed subjects these days is the energy crisis, i.e. the oil shortage and the oil price rising, which encouraged us to research and develop new green energy-hydrogen energy in the 21st century. Therefore, hydrogen produced from water splittingwith photocatalyst has been extensively studied from the viewpoint of photo energy, such as solar energy conversion to chemical and electricity energy, and environmental concerns. To date, … 相似文献
116.
Solid state 19F NMR in the temperature range from 96 to 366 K and room temperature EPR studies of fluorinated buckminsterfullerene C60F58 have been carried out. The temperature dependence of the line width and the spin-lattice relaxation time show hindered molecular motion with the activation energy of ΔEa=1.9 kcal/mol. Neither phase transition nor random rotation of C60F58 have been obtained. The spin-lattice relaxation rate is strongly affected by the presence of paramagnetic centers, namely, dangling C-C bonds yielding localized unpaired electrons. Such broken bonds are caused by C-C bond rupture in a cage-opened structure of hyperfluorinated species. 相似文献
117.
H. Hoppe M. Niggemann C. Winder J. Kraut R. Hiesgen A. Hinsch D. Meissner N.S. Sariciftci 《Advanced functional materials》2004,14(10):1005-1011
The relation between the nanoscale morphology and associated device properties in conjugated polymer/fullerene bulk‐heterojunction “plastic solar cells” is investigated. We perform complementary measurements on solid‐state blends of poly[2‐methoxy‐5‐(3,7‐dimethyloctyloxy)]‐1,4‐phenylenevinylene (MDMO‐PPV) and the soluble fullerene C60 derivative 1‐(3‐methoxycarbonyl) propyl‐1‐phenyl [6,6]C61 (PCBM), spin‐cast from either toluene or chlorobenzene solutions. The characterization of the nanomorphology is carried out via scanning electron microscopy (SEM) and atomic force microscopy (AFM), while solar‐cell devices were characterized by means of current–voltage (I–V) and spectral photocurrent measurements. In addition, the morphology is manipulated via annealing, to increase the extent of phase separation in the thin‐film blends and to identify the distribution of materials. Photoluminescence measurements confirm the demixing of the materials under thermal treatment. Furthermore the photoluminescence of PCBM clusters with sizes of up to a few hundred nanometers indicates a photocurrent loss in films of the coarser phase‐separated blends cast from toluene. For toluene‐cast films the scale of phase separation depends strongly on the ratio of MDMO‐PPV to PCBM, as well as on the total concentration of the casting solution. Finally we observe small beads of 20–30 nm diameter, attributed to MDMO‐PPV, in blend films cast from both toluene and chlorobenzene. 相似文献
118.
S. Duffe T. Irawan M. Bieletzki T. Richter B. Sieben C. Yin B. von Issendorff M. Moseler H. Hövel 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2007,45(3):401-408
The low energy deposition of silver cluster cations with
561 (±5) atoms on a cold fullerene covered gold surface has
been studied both by scanning tunneling microscopy and molecular
dynamics simulation. The special properties of the
C60/Au(111) surface result in a noticeable fixation of the
clusters without a significant change of the cluster shape. Upon
heating to room temperature we observe a flattening or shrinking
of the cluster samples due to thermal activation. Similar changes were observed also for mass selected Ag clusters with other
sizes. For comparison
we also studied Ag islands of similar size, grown by low
temperature deposition of Ag atoms and subsequent annealing. A
completely different behavior is observed with much broader size
distributions and a qualitatively different response to
annealing. 相似文献
119.
120.
X.P. Yang H.M. Weng J. Dong 《The European Physical Journal B - Condensed Matter and Complex Systems》2003,32(3):345-350
The structural, electronic, and optical properties of 4 ? single-walled carbon nanotubes (SWNTs) contained inside the zeolite
channels have been studied based upon the density-functional theory in the local-density approximation (LDA). Our calculated
results indicate that the relaxed geometrical structures for the smallest SWNTs in the zeolite channels are much different
from those of the ideal isolated SWNTs, producing a great effect on their physical properties. It is found that all three
kinds of 4 ? SWNTs can possibly exist inside the Zeolite channels. Especially, as an example, we have also studied the coupling
effect between the ALPO4-5 zeolite and the tube (5,0) inside it, and found that the zeolite has real effects on the electronic structure and optical
properties of the inside (5,0) tube.
Received 26 January 2003 Published online 11 April 2003
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ID="a"e-mail: yxptl@hotmail.com 相似文献