Nearly Exclusive Growth of Small Diameter Semiconducting Single-Wall Carbon Nanotubes from Organic Chemistry Synthetic End-Cap Molecules

Abstract

The inability to synthesize single-wall carbon nanotubes (SWCNTs) possessing uniform electronic properties and chirality represents the major impediment to their widespread applications. Recently, there is growing interest to explore and synthesize well-defined carbon nanostructures, including fullerenes, short nanotubes, and sidewalls of nanotubes, aiming for controlled synthesis of SWCNTs. One noticeable advantage of such processes is that no metal catalysts are used, and the produced nanotubes will be free of metal contamination. Many of these methods, however, suffer shortcomings of either low yield or poor controllability of nanotube uniformity. Here, we report a brand new approach to achieve high-efficiency metal-free growth of nearly pure SWCNT semiconductors, as supported by extensive spectroscopic characterization, electrical transport measurements, and density functional theory calculations. Our strategy combines bottom-up organic chemistry synthesis with vapor phase epitaxy elongation. We identify a strong correlation between the electronic properties of SWCNTs and their diameters in nanotube growth. This study not only provides material platforms for electronic applications of semiconducting SWCNTs but also contributes to fundamental understanding of the growth mechanism and controlled synthesis of SWCNTs.

Design and Synthesis of Carbon Nanotube Segments

“…[83] Zhou reported CNT growth from Scotts (5,5)CNT end-cap 161 (Scheme 45). [84] CNTs were generated from end cap 161,w hich was activated by treatment with air and water at high temperatures.E nd cap 161 was inert to CNT growth reactions without activation. Electrical transport measurements as well as Raman spectroscopy indicated that the resulting CNTs were mainly semiconducting.…”

Quantum Chemical Simulation of Carbon Nanotube Nucleation on Al2O3 Catalysts via CH4 Chemical Vapor Deposition

“…4 These approaches have combined CVD techniques with "amplification" growth, 5,6 cloning, 7,8 catalyst design, [9][10][11][12] and templated organic synthesis. [13][14][15][16][17][18][19][20][21] Of these approaches, catalyst design is arguably the most versatile and accessible method. Recent studies 12 have demonstrated that keeping the catalyst nanoparticle solid during growth is a key factor enabling the production of extremely narrow (n,m) distributions.…”

Design und Synthese von Kohlenstoffnanoröhrensegmenten

“…Demzufolge wurde nicht nur das theoretisch erwartete (5,5)CNT gebildet, sondern auch CNTs mit anderen Durch-messern. [84] Hier wurden CNTs nach einer aktivierenden Behandlung mit Luft und Wasser unter hohen Te mperaturen aus Endstück 161 erzeugt. [83] Zhou berichtete über ein CNT-Wachstum aus dem (5,5)CNT-Endstück 161 von Scott (Schema 45).…”