Understanding High-Yield Catalyst-Free Growth of Horizontally Aligned Single-Walled Carbon Nanotubes Nucleated by Activated C₆₀ Species

Abstract

Our understanding of the catalyst-free growth of single-walled carbon nanotubes by chemical vapor deposition is limited. Toward improving our knowledge base, we conducted systematic investigations into the initial preparation of C(60) fullerenes as nucleation precursors for single-wall and even double-wall carbon nanotube fabrication. The role of the dispersing media is shown to be crucial and is related to the initial fullerene cluster size. Oxygen-based groups, in particular, epoxy groups, are shown to be vital prior to actual growth. Moreover, the presence of oxygen groups during the growth phase is necessary for tube development. We also demonstrate the possibility of fabricating the tubes in crossbar configurations with bespoke crossing angles in a single synthesis step, unlike other routes which require at least two synthesis steps. The systematic studies significantly advance our understanding of the growth mechanisms involved in all-carbon catalyst-free growth of single- and double-walled carbon nanotubes.

Porous carbon-coated CuCo2O4 concave polyhedrons derived from metal–organic frameworks as anodes for lithium-ion batteries

“…Furthermore, recent studies have illustrated that the participation of carbon prevents morphological changes to the electrode and facilitates the stability of the structure. [13][14][15][16] The traditional methods for introducing carbon are by CVD, 17 glucose decomposition 18 or polymer carbonization 19 aer heating to a high temperature.…”

Confirming the Dual Role of Etchants during the Enrichment of Semiconducting Single Wall Carbon Nanotubes by Chemical Vapor Deposition

“…3,5,7,8 Therefore, the reproducible fabrication of type-selected, semiconducting (sc-) SWCNT on different substrates is crucial. 4,8 The current bottleneck is that most current SWCNT synthesis routes yield a mix of both metallic (m-) and semiconducting (sc-) SWCNT. 2,4,7 This negatively affects the performance of devices based on mixed metallic and semiconducting tubes.…”

Current Progress in the Chemical Vapor Deposition of Type-Selected Horizontally Aligned Single-Walled Carbon Nanotubes

“…2 These are difficult challenges to surmount. The combination of CVD, which is ideal for the growth of highquality long SWCNTs at the wafer scale, 3 and DEP may well be a future strategy in which the combined advantages of each approach complement each other (Figure 11). DEP would provide a strategy to deposit high densities of short seeds at chosen locations, while CVD would provide a means to repair damage as well as elongation of the predeposited seeds after activation treatments.…”

“…In previous reports, it was highlighted that functional groups attached to the open edges of the seeds during the treatment step are crucial for the successful elongation of the seeds. The type and influence of functional groups attached to the seeds on their ability to successfully nucleate the growth of SWCNTs was systematically investigated by Ibrahim et al 3 However, in this study, fullerene fragments were used to nucleate the growth of SWCNTs after proper treatment in order to open the fullerenes and activate their edges (a process first demonstrated by the Liu group at Peking University). The spectroscopic characterizations from the different process steps highlight that epoxy (C−O) groups are relatively more abundant than carbonyl (CO) groups, and more importantly, their level is strongly dependent on the solvent in which the fullerenes were dissolved.…”

“…This study excluded the effect of trace oxygen residue on the selective growth of semiconducting SWCNTs in contrast to many reports. 3,132 However, one can expect that the corannulene molecules are unstable at the high growth temperatures used, which may cause their deterioration and/or merging, resulting in the growth of SWCNTs with different diameters. Thus, it is realistic to contemplate that the growth of semiconducting-rich SWCNTs is due to both the growth conditions and the nature of nucleators.…”