SWCNT networks on nanoporous silica catalyst support : morphological and connectivity control for nanoelectronic, gas-sensing, and biosensing devices


Autoria(s): Han, Zhao Jun; Mehdipour, Hamid; Li, Xiaoguang; Shen, Jun; Randeniya, Lakshman; Yang, Hui Ying; Ostrikov, Kostya
Data(s)

2012

Resumo

Effective control of morphology and electrical connectivity of networks of single-walled carbon nanotubes (SWCNTs) by using rough, nanoporous silica supports of Fe catalyst nanoparticles in catalytic chemical vapor deposition is demonstrated experimentally. The very high quality of the nanotubes is evidenced by the G-to-D Raman peak ratios (>50) within the range of the highest known ratios. Transitions from separated nanotubes on smooth SiO2 surface to densely interconnected networks on the nanoporous SiO2 are accompanied by an almost two-order of magnitude increase of the nanotube density. These transitions herald the hardly detectable onset of the nanoscale connectivity and are confirmed by the microanalysis and electrical measurements. The achieved effective nanotube interconnection leads to the dramatic, almost three-orders of magnitude decrease of the SWCNT network resistivity compared to networks of similar density produced by wet chemistry-based assembly of preformed nanotubes. The growth model, supported by multiscale, multiphase modeling of SWCNT nucleation reveals multiple constructive roles of the porous catalyst support in facilitating the catalyst saturation and SWCNT nucleation, consistent with the observed higher density of longer nanotubes. The associated mechanisms are related to the unique surface conditions (roughness, wettability, and reduced catalyst coalescence) on the porous SiO2 and the increased carbon supply through the supporting porous structure. This approach is promising for the direct integration of SWCNT networks into Si-based nanodevice platforms and multiple applications ranging from nanoelectronics and energy conversion to bio- and environmental sensing.

Identificador

http://eprints.qut.edu.au/74699/

Publicador

American Chemical Society

Relação

DOI:10.1021/nn302020a

Han, Zhao Jun, Mehdipour, Hamid, Li, Xiaoguang, Shen, Jun, Randeniya, Lakshman, Yang, Hui Ying, & Ostrikov, Kostya (2012) SWCNT networks on nanoporous silica catalyst support : morphological and connectivity control for nanoelectronic, gas-sensing, and biosensing devices. ACS Nano, 6(7), pp. 5809-5819.

Direitos

Copyright 2012 American Chemical Society

Fonte

School of Chemistry, Physics & Mechanical Engineering; Science & Engineering Faculty

Palavras-Chave #single-walled carbon nanotubes #nanonetworks #nanoscale electrical connectivity #porous catalyst support #graphene layer
Tipo

Journal Article