Mo–Co catalyst nanoparticles: Comparative study between TiN and Si surfaces for single-walled carbon nanotube growth

• Published in: Thin solid films Vol. 520; no. 16; pp. 5232 - 5238
• Main Authors: Morant, C., Campo, T., Márquez, F., Domingo, C., Sanz, J.M., Elizalde, E.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 01.06.2012; Elsevier
• Subjects: Catalysis; Catalysts; Catalysts: preparations and properties; Chemical vapor deposition; Chemistry; Cross-disciplinary physics: materials science; rheology; Exact sciences and technology; Field emission; General and physical chemistry; Materials science; Methods of deposition of films and coatings; film growth and epitaxy; Molybdenum; Mo–Co catalysts; Nanoparticles; Nanoscale materials and structures: fabrication and characterization; Nanotubes; Other topics in nanoscale materials and structures; Physics; Silicon; Single wall carbon nanotubes; Single-walled carbon nanotubes; Theory and models of film growth; Theory of reactions, general kinetics. Catalysis. Nomenclature, chemical documentation, computer chemistry; Thin films; Titanium nitride; Titanium nitride; Mo–Co catalysts; Chemical vapor deposition; Single-walled carbon nanotubes; Hot filament chemical vapor deposition; Atomic force microscopy; Scanning electron microscopy; Mo-Co catalysts; Nanoparticle; Carbon nanotubes; Alcohol; Field emission; Coatings; Carbon; Molybdenum; Singlewalled nanotube; Experimental result; Growth mechanism; Silicon; Raman spectrometry; Nanostructured materials; Catalyst; Comparative study; X-ray photoelectron spectra
• ISSN: 0040-6090; 1879-2731
• DOI: 10.1016/j.tsf.2012.03.099

Highly pure single-walled carbon nanotubes (SWNT) were synthesized by alcohol catalytic chemical vapor deposition on silicon substrates partially covered by a thin layer of TiN. The TiN coating selectively prevented the growth of carbon nanotubes. Field emission scanning electron microscopy and Raman spectroscopy revealed the formation of high purity vertically aligned SWNT in the Si region. X-ray Photoelectron Spectroscopy and Atomic Force Microscopy indicated that Co nanoparticles are present on the Si regions, and not on the TiN regions. This clearly explains the obtained experimental results: the SWNT only grow where the Co is presented as nanoparticles, i.e. on the Si regions. ► Single-wall carbon nanotubes (SWNT) ontained by catalytic chemical vapor-deposition. ► Substrate/Co-Mo catalyst behaviour plays a key role in the SWNT growth. ► Co nanoparticles (the effective catalyst) have been only observed on the Si region. ► High purity SWNT were spatially confined in specific locations (Si regions). ► TiN-coated surfaces, adjacent to a Si oxide region, prevent the growth of SWNT.