Fabrication of vertically aligned carbon nanostructures by microwave plasma-enhanced chemical vapor deposition

et al. 2019

Appl. Phys. Express

Carbon nanowalls (CNWs) were synthesized by radical injection plasma-enhanced chemical vapor deposition and used as scaffolds for cell culture. The proliferation of osteoblast-like cells (Saos-2) was enhanced on the CNW scaffold upon electrical stimulation (ES) with 10 Hz square pulses at a current of 226 nA. However, after incubation with ES for 10 d, differentiation of the cells toward bone formation was suppressed.

mentioning

confidence: 99%

“…Details of the RI-PECVD system have been given in previous reports and recent reviews. [3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19] The flow rate of methane (CH 4 ) was 100 sccm, and that of hydrogen (H 2 ) was 50 sccm. The substrate temperature was 650 °C, and the total pressure was 1 Pa.…”

mentioning

confidence: 99%

Effect of electrical stimulation on proliferation and bone-formation by osteoblast-like cells cultured on carbon nanowalls scaffolds

Ichikawa

Tanaka

et al. 2019

Appl. Phys. Express

“…15) In another approach, chemical vapor deposition (CVD) methods for carbon nanomaterial synthesis have been extensively reported. [16][17][18] For example, carbon nanowalls are nanographene sheets that stand vertically on a substrate by growth in low-pressure CH 4 =H 2 or C 2 F 6 =H 2 plasma at high temperatures; [19][20][21] these gas-phase processes have been successfully used to fabricate nanographene sheets or flakes. In contrast, few studies on the synthesis of graphene flakes at atmospheric pressure have been reported, such as with submerged discharges in liquids.…”

mentioning

confidence: 99%

Rapid growth of micron-sized graphene flakes using in-liquid plasma employing iron phthalocyanine-added ethanol

Amano

Ishikawa

et al. 2017

Appl. Phys. Express

Giant graphene flakes on the micron scale were synthesized and grown in plasmas in liquid-phase pure ethanol with added iron phthalocyanine (FePc) in a solvent. At atmospheric pressure, plasmas were generated in the gas phase filled with Ar and in the liquid phases comprising bubbles and liquid solutions. In the mixture of FePc in ethanol, nanographene sheets aggregated to form giant graphene flakes, as confirmed by the D, G, and 2D bands in the corresponding Raman spectra. Therefore, a bottom-up approach of graphite synthesis from pure ethanol with additives and a catalyst was realized by in-liquid plasma processing.

“…[12][13][14] Various substrates including silicon, silicon oxides, and metals with no metal catalysts, such as nickel, iron, and cobalt were used. 15) In recent years, we have reported the highly reproducible growth of CNWs by plasma-enhanced chemical vapor deposition with radical injection (RI-PECVD) employing the C 2 F 6 and H 2 mixture plasma, and high controllability of their morphology and electrical properties. 16) Furthermore, it has also been found that CNWs have semiconducting properties.…”

mentioning

confidence: 99%

Effects of nitrogen plasma post-treatment on electrical conduction of carbon nanowalls

Cho

Ishikawa

et al. 2014

Jpn. J. Appl. Phys.

For utilization in future electronic application of graphene materials, nitrogen (N) atom doping into graphene sheets is an important technology. We investigated the electrical conduction of carbon nanowalls (CNWs), consisting of stacks of graphene sheets standing vertically on substrates. By post-treatment for 30 s, the electrical conductivity of CNWs increased. On the other hand, as the post-treatment time increased, the electrical conductivity decreased. According to Hall measurement, the carrier density decreased with increasing post-treatment time, while the carrier mobility increased. Consequently, the electrical conduction of the CNWs was successfully controlled by N2 plasma treatment.