Electron-microscope studies of structural heterogeneity in pan-based carbon fibres

Synthesis of the Tube-Brush-Shaped SiC Nanowire Array on Carbon Fiber and Its Photoluminescence Properties

“…Figure 3(c) shows a typical cross-sectional view of carbon fiber after 9 hours' reaction, in which a skin/core heterogeneity and radial channels within the core are clearly seen. This is similar to what Bennett et al 19 reported on the skin/core heterogeneity structure of PAN carbon fiber. Energy dispersive X-ray spectrometry (EDS) analysis (Fig.…”

“…In this case no catalyst was used and no metal droplet was found at the ends of the nanowires, therefore, the vapor-solid growth mechanism is more plausible than the vapor-liquid-solid mode. According to the research on the structure of PAN carbon fiber by Bennett et al, 19 graphite crystallite architecture just below the skin of carbon fiber was well orientated and parallel to the skin, and random at the core where amorphous carbon was also situated. Poor crystalline structure shown by the XRD profile of asreceived PAN carbon fiber (Fig.…”

Synthesis and photoluminescence of needle-shaped 3C–SiC nanowires on the substrate of PAN carbon fiber

“…One reported that the PAN carbon fibres had skin/core heterogeneity and crystallite organization of graphite was parallel to the surface in the skin and random in the core. Moreover, large misoriented crystallites which were considered to be flaws had been observed in the skin of the fibers [16]. We thought that the flaws might be the channels through which the active carbon atoms in the core traversed the crystallite skin to react with Si atoms from Si vapor deposited on the flaws.…”

Thermal analysis studies on electrochemically oxidized carbon fibers

“…1) of all the tested carbon fibers (with the exception of Celion reveal two exothermic maxima in the temperature range up to 700 K. This is probably due to the heterogeneous skin/core type of the tested carbon fibers [9]. The skin of the fibers consists of well-developed graphite crystallites arranged parallel to the fiber axis, while the core is characterized by a much poorer random ordering of the crystaUites [1,12].…”