Publications by authors named "Christoph T Wirth"

We present a systematic study of the temperature and pressure dependence of the growth rate of vertically aligned small diameter (single- and few-walled) carbon nanotube forests grown by thermal chemical vapor deposition over the temperature range 560-800 degrees C and 10(-5) to 14 mbar partial pressure range, using acetylene as the feedstock and Al(2)O(3)-supported Fe nanoparticles as the catalyst. We observe a pressure dependence of P(0.6) and activation energies of <1 eV.

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Self-assembled nanowires offer the prospect of accurate and scalable device engineering at an atomistic scale for applications in electronics, photonics and biology. However, deterministic nanowire growth and the control of dopant profiles and heterostructures are limited by an incomplete understanding of the role of commonly used catalysts and specifically of their interface dynamics. Although catalytic chemical vapour deposition of nanowires below the eutectic temperature has been demonstrated in many semiconductor-catalyst systems, growth from solid catalysts is still disputed and the overall mechanism is largely unresolved.

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