The Role of Sulfur in the Synthesis of Novel Carbon Morphologies: From Covalent Y‐Junctions to Sea‐Urchin‐Like Structures

A detailed characterization, using high resolution electron microscopy/microanalysis (SEM, TEM, HRTEM, and EDX), reveals tubular carbon nanostructures exhibiting complex and fascinating morphologies. The materials were obtained by sulfur‐assisted chemical vapor deposition. It is demonstrated that S not only acts on the catalyst, but also can be detected in the carbon lattice of the nanostructures. The experimental data presented here confirms the critical role of S, which is responsible for inducing curvature and therefore influencing the final carbon nanostructure morphology. In particular, different types of covalent Y‐junctions of CNTs and even sea urchin‐like nanostructures were produced and their experimental conditions are listed and discussed.

[1]  Y. Gogotsi,et al.  Materials for electrochemical capacitors. , 2008, Nature materials.

[2]  X. Jia,et al.  Bulk production of a new form of sp(2) carbon: crystalline graphene nanoribbons. , 2008, Nano letters.

[3]  I. Kinloch,et al.  The role of sulphur in the synthesis of carbon nanotubes by chemical vapour deposition at high temperatures. , 2008, Journal of nanoscience and nanotechnology.

[4]  B. Sumpter,et al.  An atomistic branching mechanism for carbon nanotubes: sulfur as the triggering agent. , 2008, Angewandte Chemie.

[5]  A special issue on polymer nanocomposites. , 2008, Journal of nanoscience and nanotechnology.

[6]  M. Terrones,et al.  Covalent 2D and 3D networks from 1D nanostructures: designing new materials. , 2007, Nano letters.

[7]  Q. Guo,et al.  Carbon with high thermal conductivity, prepared from ribbon-shaped mesosphase pitch-based fibers , 2006 .

[8]  G. U. Kulkarni,et al.  Nature and electronic properties of Y-junctions in CNTs and N-doped CNTs obtained by the pyrolysis of organometallic precursors , 2005 .

[9]  Ya-Li Li,et al.  Direct Spinning of Carbon Nanotube Fibers from Chemical Vapor Deposition Synthesis , 2004, Science.

[10]  C. Boothroyd,et al.  Synthesis and Characterization of Carbon Nanofibers Produced by the Floating Catalyst Method , 2002 .

[11]  Ji Liang,et al.  Growth mechanism of Y-junction carbon nanotubes , 2002 .

[12]  A. Govindaraj,et al.  Synthetic strategies for Y-junction carbon nanotubes , 2001 .

[13]  Ji Liang,et al.  Carbon nanofibers and single-walled carbon nanotubes prepared by the floating catalyst method , 2001 .

[14]  A. Sakoda,et al.  Formation of vapor grown carbon fibers with sulfuric catalyst precursors and nitrogen as carrier gas , 2001 .

[15]  R. L. Wal,et al.  Directed Synthesis of Metal-Catalyzed Carbon Nanofibers and Graphite Encapsulated Metal Nanoparticles , 2000 .

[16]  C. N. R. Rao,et al.  Y-junction carbon nanotubes , 2000 .

[17]  G. Tibbetts,et al.  Increase in yield of carbon fibres grown above the iron/carbon eutectic , 1999 .

[18]  M. Dresselhaus,et al.  Large-scale and low-cost synthesis of single-walled carbon nanotubes by the catalytic pyrolysis of hydrocarbons , 1998 .

[19]  D. Bethune,et al.  Vapor-phase self-assembly of carbon nanomaterials , 1996 .

[20]  J. R. Abeysinghe,et al.  New Horizons in Carbon Chemistry and Materials Science , 1994 .

[21]  Gary G. Tibbetts,et al.  Role of sulfur in the production of carbon fibers in the vapor phase , 1994 .

[22]  K. Kusakabe,et al.  Effect of sulphur on formation of vapour-grown carbon fibre , 1994 .

[23]  M. Kim,et al.  The interplay between sulfur adsorption and carbon deposition on cobalt catalysts , 1993 .

[24]  M. Egashira,et al.  Formation of carbon fibers from naphthalene on some sulfur-containing substrates , 1981 .