The use of organometallic transition metal complexes in the synthesis of shaped carbon nanomaterials

Nyamori, Vincent O. (NRF Centre of Excellence in Strong Materials, the School of Chemistry, University of the Witwatersrand); Mhlanga, Sabelo D.; Coville, Neil J. Source: Journal of Organometallic Chemistry, v 693, n 13, Jun 15, 2008, p 2205-2222
ISSN: 0022-328X CODEN: JORCAI
Publisher: Elsevier

Abstract: A review of the use of organometallic complexes in the synthesis of shaped carbon nanomaterials (SCNMs), in particular carbon nanotubes (CNTs) has been undertaken. This review reveals that a limited number of organometallic complexes have been used as catalysts (typically ferrocene, Fe(CO)₅) to make carbon materials that have distinctive shapes. Depending on the reaction conditions employed, ferrocene can be used to synthesize single walled (SWCNTs), double walled (DWCNTs) and multiwalled nanotubes (MWCNTs) as well as fibres and other SCNMs. The type of reactor used as well as the reaction conditions (temperature, pressure, gas flow rates, etc.) and the presence of hydrogen and heteroatoms (N, O, S, P, etc.) also play a role in determining the final carbon types (and their sizes) that have been synthesized. The influence of the various chemical and physical factors on the carbons produced are discussed. The current mechanism used to explain the formation of CNTs is described. © 2008 Elsevier B.V. All rights reserved. (213 refs.)

terms:  Carbon nanotubes  -  Flow rate  -  Hydrogen  -  Organometallics  -  Pressure effects  -  Synthesis (chemical)  -  Thermal effects  -  Transition metal compounds