Growth of semiconducting single-wall carbon nanotubes with a narrow band-gap distribution.

Feng Zhang,Mao-Lin Chen,Jin-Cheng Li,Peng-Xiang Hou,Hui-Ming Cheng,Hong-Tao Cong,Dong-Ming Sun,Bing-Wei Wang,Chang Liu,Esko I Kauppinen,Hua Jiang

doi:10.1038/ncomms11160

Abstract

The growth of high-quality semiconducting single-wall carbon nanotubes with a narrow band-gap distribution is crucial for the fabrication of high-performance electronic devices. However, the single-wall carbon nanotubes grown from traditional metal catalysts usually have diversified structures and properties. Here we design and prepare an acorn-like, partially carbon-coated cobalt nanoparticle catalyst with a uniform size and structure by the thermal reduction of a [Co(CN)6]3− precursor adsorbed on a self-assembled block copolymer nanodomain. The inner cobalt nanoparticle functions as active catalytic phase for carbon nanotube growth, whereas the outer carbon layer prevents the aggregation of cobalt nanoparticles and ensures a perpendicular growth mode. The grown single-wall carbon nanotubes have a very narrow diameter distribution centred at 1.7 nm and a high semiconducting content of >95%. These semiconducting single-wall carbon nanotubes have a very small band-gap difference of ∼0.08 eV and show excellent thin-film transistor performance.

Highlights

The growth of high-quality semiconducting single-wall carbon nanotubes with a narrow band-gap distribution is crucial for the fabrication of high-performance electronic devices
The [Co(CN)6]3 À catalyst precursor was absorbed on the phase-separated P4VP nanodomains so that only part of the Co nanoparticle is exposed and serves as the catalyst for SWCNT growth following a perpendicular mode
As the Co nanoparticles prepared by the copolymer self-assembly method have a narrow range of diameters, the exposed Co active catalyst obtained after polymer wrapping and partial etching processes should have an even smaller size difference

Summary

Introduction

The growth of high-quality semiconducting single-wall carbon nanotubes with a narrow band-gap distribution is crucial for the fabrication of high-performance electronic devices. Zhang and colleagues[15] grew s-SWCNT arrays by applying ultraviolet irradiation and subsequent photochemical reactions; Liu and colleagues[16] prepared SWCNTs by using a mixture of ethanol and methanol as both carbon source and oxidant precursor; Cheng and colleagues[17,18] synthesized s-SWCNTs by introducing oxygen or hydrogen as etchants; and Li and colleagues[19] grew s-SWCNTs from a metal catalyst loaded on CeO2 supports that can release oxygen for selective etching In these above studies, high-quality s-SWCNTs with purities higher than 90% were obtained. The inner Co nanoparticle functions as active catalytic phase for SWCNT growth, whereas the outer carbon layer prevents the aggregation of Co nanoparticles and ensures the perpendicular growth of SWCNT from the catalyst This acorn-like catalyst with uniform size and structure is prepared using a block copolymer (BCP) self-assembly technique[30]. High-purity (495%) s-SWCNTs with a narrow range of band gaps (o0.08 eV) are obtained, which show an excellent thin-film transistor (TFT) performance

Methods

Results

Conclusion