Journal Article10.1143/JPSJ.69.754
Novel Electronic Properties of a Nano-Graphite Disordered Network and Their Iodine Doping Effects.
Yoshiyuki Shibayama,Hirohiko Sato,Toshiaki Enoki,Xiang–Xin Bi,Mildred S. Dresselhaus,Morinobu Endo +5 more
82
TL;DR: In this article, the authors investigated the structure, electronic properties and iodine doping effects for activated carbon fibers (ACFs) samples heat-treated up to 2800° C, showing that ACFs exhibit Coulomb gap variable-range hopping conduction and the presence of localized spins.
read more
Abstract: Activated carbon fibers (ACFs) are microporous carbons consisting of a three-dimensional disordered network of nano-graphites with a mean in-plane size of about 30 A. We investigated the structure, electronic properties and iodine doping effects for ACF samples heat-treated up to 2800° C. The samples heat-treated below 1000° C exhibit Coulomb gap variable-range hopping conduction and the presence of localized spins, suggesting the importance of charging effects and the edge-inherited non-bonding states in nano-graphites, the latter being predicted theoretically. Iodine doping reduces the charging effect due to the dielectric constant enhanced by the iodine that is accommodated in the micropores. Heat treatment above 1300° C changes ACFs from an Anderson insulator to a disordered metal by the development of an infinite inter-nano-graphite percolation path network for electron transport, accompanied by a change from localized-spin magnetism to itinerant electron magnetism. In the metallic regime, carrier sc...
read more
Chat with Paper
AI Agents for this Paper
Find similar papers on Google Scholar, PubMed and Arxiv
Write a critical review of this paper
Analyze citations of this paper to find unaddressed research gaps
Citations
On the chemical nature of graphene edges: origin of stability and potential for magnetism in carbon materials.
TL;DR: It is proposed that under ambient conditions a significant fraction of the oxygen-free edge sites are neither H-terminated nor unadulterated sigma free radicals, as universally assumed, which can explain the recently documented and heretofore puzzling ferromagnetic properties of some impurity-free carbon materials.
555
Scanning tunneling microscopy and spectroscopy of the electronic local density of states of graphite surfaces near monoatomic step edges
TL;DR: In this paper, the authors measured the electronic local density of states (LDOS) of graphite surfaces near monoatomic step edges, which consist of either the zigzag or armchair edge, with the scanning tunneling microscopy (STM) and spectroscopy techniques.
Electronic structures of graphene edges and nanographene
TL;DR: The electronic structure of nanographene has a non-bonding π-electron state (edge state) localized in zigzag edges as mentioned in this paper, which is reminiscent of the non-kekule-type aromatic molecules.
244
Alkali metal iodide/carbon interface as a source of pseudocapacitance
TL;DR: In this paper, the pseudocapacitive effects originating from the alkali metal iodide/carbon interface have been studied in aqueous medium, and five different solutions, i.e., lithium, sodium, potassium, rubidium and caesium iodides, have been tested as electrolyte in supercapacitors.
182
Structure and electronic properties of a nongraphitic disordered carbon system and its heat-treatment effects
Kazuyuki Takai,Meigo Oga,Hirohiko Sato,Toshiaki Enoki,Yoshimasa Ohki,Akira Taomoto,Kazutomo Suenaga,Sumio Iijima +7 more
TL;DR: In this article, the heat treatment effect on electronic properties is investigated in relation to structural change for pulsed-laser-deposited amorphous carbon thin films having a ratio of approximately 9.
132
References
Raman Spectrum of Graphite
F. Tuinstra,J. L. Koenig +1 more
TL;DR: Raman spectra are reported from single crystals of graphite and other graphite materials as mentioned in this paper, and the Raman intensity of this band is inversely proportional to the crystallite size and is caused by a breakdown of the k-selection rule.
10.4K
Peculiar Localized State at Zigzag Graphite Edge
TL;DR: In this article, the electronic states of graphite ribbons with edges of two typical shapes, armchair and zigzag, were studied by performing tight binding band calculations, and it was shown that the graphite ribbon showed striking contrast in the electronic state depending on the edge shape.
2.9K
Characterization of diamond films by Raman spectroscopy
Diane S. Knight,William B. White +1 more
TL;DR: The Raman spectrum of hexagonal diamond (lonsdaleite) is distinct from that of the cubic diamond and allows it to be recognized as discussed by the authors, and the Raman line width varies with mode of preparation of the diamond and has been related to degree of structural order.
2.5K
Coulomb gap and low temperature conductivity of disordered systems
A. L. Efros,Boris I Shklovskii +1 more
TL;DR: In this paper, the Coulomb interaction between localized electrons is shown to create a soft gap in the density of states near the Fermi level, and the form of the density within the gap is discussed.
2.4K
Mechanisms for Lithium Insertion in Carbonaceous Materials
TL;DR: Lithium can be inserted reversibly within most carbonaceous materials as mentioned in this paper, but the physical mechanism for this insertion depends on the carbon type and the type of carbon type used.
2K