STM and XPS studies of early stages of carbon nanotube growth by surface decomposition of 6H–SiC(000-1) under various oxygen pressures

Initial Growth Process of Carbon Nanotubes in Surface Decomposition of SiC

“…However, few studies have been reported with combing XPS measurement and STM observation for formation process of carbon nanocaps. Here, we carried out both XPS measurements and STM observations for carbon nanocaps formed on 6H-SiC(000-1) (Maruyama et al, , 2007. Figure 5(a) and (b) show XPS spectra of 6H-SiC(000-1) surface before and after heating at 1100ºC in UHV, respectively, where the spectrum of Fig.…”

“…Fig. 12 shows a phase diagram for the interaction of O 2 with the SiC surface, where formation of carbon nanocaps and SiO 2 are separately shown (Maruyama et al, 2007). All data were obtained by heating the 6H-SiC(000-1) in a vacuum electronic furnace and in a UHV chamber where the oxygen gas was introduced by controlling the pressure, and the heating rates were kept below 1ºC/min which were low enough to form carbon nanocaps.…”

Growth of Graphene-Like Structures on an Oxidized SiC Surface

“…2, possibly via the formation of silicon oxycarbides, such as Si 4 C 4Àx O 2 , at the initial stage of SiC surface graphitization. 20 The degree of surface graphitization on SiC is temperature dependent. It has been shown that, as the temperature varies from 900°C to 1250°C, carbon rich (6Ö3 9 6Ö3R30) and (6 9 6) reconstructions on the Si-face of SiC are formed under UHV, 21 and the initial surface carbon layer has a low degree of graphitization.…”

“…It is generally agreed that either low pressure residual oxygen at high vacuum or the surface oxygen-containing compounds contribute to SiC surface oxidation and promote carbon nanocaps and CNT growth. 20 In a UHV, the residual oxygen is at a negligible level, and the surface oxygen-containing compounds are removed by the Si flux at high temperature, 15,17 and it is assumed that SiC decomposes as silicon and carbon, as in Eq. 3.…”

Analysis of chemical polymerization between functionalized MWCNT and poly(furfuryl alcohol) composite

“…The neat CNT was a reference to evaluate the efficiency of functionalization with carboxylic groups. Figure 7 shows the curve fitting of C 1s and O 1s core levels [21][22][23] for neat (Figure 7a1 and 7a2) and functionalized CNT with H 2 SO 4 :HNO 3 (Figure 7b1 and 7b2), respectively. The C 1s spectrum was deconvoluted in six components: C-C (~284.52 eV), C-H (~285.36 eV), C-O (~286.58 eV), C=O (~287.58 eV), O-C=O (~288.58 eV), and plasmon p-p* (~290.82 eV).…”