TY - JOUR
T1 - Catalyst nucleation and carbon nanotube growth from flame-synthesized Co-Al-O nanopowders at ten-second time scale
AU - Shirae, Hiroyuki
AU - Hasegawa, Kei
AU - Sugime, Hisashi
AU - Yi, Eongyu
AU - Laine, Richard M.
AU - Noda, Suguru
N1 - Funding Information:
The authors thank Mr. Shinpei Enomoto at Kagami Memorial Research Institute for Materials Science and Technology, Waseda University for TEM observation. XRD and ICP-OES measurements were performed at Materials Characterization Central Laboratory, Waseda University. This work is financially supported by the Advanced Low Carbon Technology Research and Development Program (ALCA) by JST, Japan and JSPS KAKENHI Grant Numbers JP25107002 and JP16H06368 , Japan. H.S. acknowledges the Leading Graduate Program in Science and Engineering, Waseda University from MEXT, Japan. The Laine group thanks NSF DMR for support through DMR grant 1105361 .
Publisher Copyright:
© 2016 Elsevier Ltd
PY - 2017/4/1
Y1 - 2017/4/1
N2 - Flame-synthesized (CoO)x(Al2O3)1-x spinel nanopowders with primary particles of ∼20 nm were used to grow small diameter carbon nanotubes (CNTs). The nanopowders with x ≤ 0.35 grew few CNTs whereas that with x = 0.65 grew CNTs efficiently. Low crystalline and large-diameter multi-wall CNTs grew by annealing and chemical vapor deposition (CVD) at 800 °C for ∼10 min, whereas single-wall CNTs with high crystallinity (G-band to D-band intensity ratio of 20–100 by Raman spectroscopy) grew by annealing and CVD at ≥1000 °C for ∼10 s. The excess Co in the spinel reduced and segregated to form multiple Co nanoparticles on the surface of the single primary alumina nanoparticles in ∼10 s, yielding SWCNTs in ∼10 s. Such flame synthesized nanopowders, reduced and activated by H2, provide CNTs from C2H2, all in ten-second time scale, and as such are promising for practical, high-through-put production of small-diameter CNTs.
AB - Flame-synthesized (CoO)x(Al2O3)1-x spinel nanopowders with primary particles of ∼20 nm were used to grow small diameter carbon nanotubes (CNTs). The nanopowders with x ≤ 0.35 grew few CNTs whereas that with x = 0.65 grew CNTs efficiently. Low crystalline and large-diameter multi-wall CNTs grew by annealing and chemical vapor deposition (CVD) at 800 °C for ∼10 min, whereas single-wall CNTs with high crystallinity (G-band to D-band intensity ratio of 20–100 by Raman spectroscopy) grew by annealing and CVD at ≥1000 °C for ∼10 s. The excess Co in the spinel reduced and segregated to form multiple Co nanoparticles on the surface of the single primary alumina nanoparticles in ∼10 s, yielding SWCNTs in ∼10 s. Such flame synthesized nanopowders, reduced and activated by H2, provide CNTs from C2H2, all in ten-second time scale, and as such are promising for practical, high-through-put production of small-diameter CNTs.
UR - http://www.scopus.com/inward/record.url?scp=85002844499&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85002844499&partnerID=8YFLogxK
U2 - 10.1016/j.carbon.2016.11.075
DO - 10.1016/j.carbon.2016.11.075
M3 - Article
AN - SCOPUS:85002844499
SN - 0008-6223
VL - 114
SP - 31
EP - 38
JO - Carbon
JF - Carbon
ER -