Carbon nanotube growth on conductors: Influence of the support structure and catalyst thickness

• Published in: Carbon (New York) 2014-07, Vol.73, p.13-24
• Main Authors: Esconjauregui, S., Bhardwaj, S., Yang, J., Castellarin-Cudia, C., Xie, R., D’Arsié, L., Makaryan, T., Sugime, H., Fernandez, S.E., Cepek, C., Robertson, J.
• Format: Article
• Language: English
• Subjects: Carbon; Catalysis; Catalysts; Chemistry; Cross-disciplinary physics: materials science; rheology; Exact sciences and technology; Forests; Fullerenes and related materials; diamonds, graphite; General and physical chemistry; Materials science; Nanoparticles; Nanoscale materials and structures: fabrication and characterization; Nanostructure; Nanotubes; Oxides; Physics; Specific materials; Stability; Theory of reactions, general kinetics. Catalysis. Nomenclature, chemical documentation, computer chemistry; Titanium nitride
• ISSN: 0008-6223; 1873-3891
• DOI: 10.1016/j.carbon.2014.02.026

We investigate the formation and stability of Fe nanoparticles on TiN and poly-crystalline PtSi films, and their ability to grow carbon nanotubes forests. Using different-microstructure films, coated with or without their native oxides, we show that, upon purely-thermal catalyst pretreatment, PtSi favours the formation of homogenously sized nanoparticles and forest growth, partly due to its low surface energy. TiN, in contrast, leads to much less controllable processes and only when coated with its native oxide, or with thick catalyst films, yields large diameter nanotube forests. The microstructure of the material can dramatically limit catalyst diffusion into the bulk of the support during nanotube growth. These results allow us to establish the general behaviour expected for nanotube growth on any conductive materials.