corner
corner

Phys. Rev. Lett. 100, 176803 (2008) [4 pages]

Designing Real Nanotube-Based Gas Sensors

Download: PDF (693 kB) Buy this article Export: BibTeX or EndNote (RIS)

A. R. Rocha1,2, M. Rossi1,*, A. Fazzio1,2, and Antonio J. R. da Silva1,†
1Instituto de Física, Universidade de São Paulo, CP 66318, 05315-970, São Paulo, SP, Brazil
2Centro de Ciências Naturais e Humanas, Universidade Federal do ABC, Santo André, SP, Brazil

Received 14 December 2007; published 29 April 2008

Using a combination of density functional theory and recursive Green‘s functions techniques, we present a full description of a large scale sensor, accounting for disorder and different coverages. Here, we use this method to demonstrate the functionality of nitrogen-rich carbon nanotubes as ammonia sensors as an example. We show how the molecules one wishes to detect bind to the most relevant defects on the nanotube, describe how these interactions lead to changes in the electronic transport properties of each isolated defect, and demonstrate that there are significative resistance changes even in the presence of disorder, elucidating how a realistic nanosensor works.

© 2008 The American Physical Society

URL:
http://link.aps.org/doi/10.1103/PhysRevLett.100.176803
DOI:
10.1103/PhysRevLett.100.176803
PACS:
73.63.Fg, 07.07.Df, 71.23.−k, 72.10.Bg

*Present address: Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, D-14195 Berlin (Dahlem), Germany

ajrsilva@if.usp.br