Structure and texture of filamentous carbons produced by methane decomposition on NI and NI-CU catalysts

Adsorption Methods of Hydrogen and Methane Storage for the Fuel Cell Application

“…The carbon fibers used in [8,9] have a long history [15,16], and were studied many times from the different viewpoints, see, for example, [17][18][19][20][21][22][23]. In the literature they are called graphite nanofibers (GNF) [8,9], carbon nanofibers (CNF) [10,23], vapor-grown carbon fibers (VGCF) [7], carbon nano-tubes (CNT) [24] etc.…”

“…They are even more different from the popular single-walled nanotubes (SWNT). Therefore, in order to avoid confusion, we prefer to call them сatalytic filamentous carbon (CFC) [21,22], implying under CFC the fibers which are formed as a result of catalytic decomposition of a precursor hydrocarbon on the active face of catalyst metal nanoparticle, diffusion of the carbon through this particle and its yield on the face, which is coherent to the graphite structure [22].…”

“…In the Boreskov Institute of Catalysis were conducted the detailed studies of molecular and supramolecular structure (texture) of CFC, obtained via the methane decomposition over Ni and Ni-Cu catalysts at 823-848 K, see, for example, [21,22,25,26]. It was shown, that the graphite planes (graphenes) stacking arrangement near the surface of studied CFC is substantially different from their stacking in the bulk of filament, because graphenes on the surface tend to be parallel to the filament axis.…”

“…It was shown, that the graphite planes (graphenes) stacking arrangement near the surface of studied CFC is substantially different from their stacking in the bulk of filament, because graphenes on the surface tend to be parallel to the filament axis. According to the data of high resolution transmission electron microscopy (HRTEM) and scanning tunnelling microscopy (STM) [21,22], the surface of CFC having the herringbone bulk structure (further -type I) is covered by the steps and terraces formed from the graphenes. In its turn, the surface of CFC having the plateled bulk structure (further -type II) is covered by the curved "closed layers" or "caps".…”

Catalytic decomposition of methane over supported Ni catalysts with different particle sizes

“…[1] Now, CNFs are the subject of numerous studies for their unique properties, such as high resistance to strong acids and bases, high electronic conductivity (similar to graphite), large surface area, and strong mechanical strength, [2,3] which make them a promising material for various applications, including polymer filler, absorbent, [2,3] catalyst, [4,5] and catalyst support. [6,7] Efforts to explore the use of CNFs in electrochemistry are also increasing, either for use in the high-power electrochemical capacitor or in the fuel cell as part of the electrode.…”