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arXiv · 1112.1052

Computational design of chemical nanosensors: Transition metal doped single-walled carbon nanotubes

Abstract

We present a general approach to the computational design of nanostructured chemical sensors. The scheme is based on identification and calculation of microscopic descriptors (design parameters) which are used as input to a thermodynamic model to obtain the relevant macroscopic properties. In particular, we consider the functionalization of a (6,6) metallic armchair single-walled carbon nanotube (SWNT) by nine different 3d transition metal (TM) atoms occupying three types of vacancies. For six gas molecules (N_{2}, O_{2}, H_{2}O, CO, NH_{3}, H_{2}S) we calculate the binding energy and change in conductance due to adsorption on each of the 27 TM sites. For a given type of TM functionalization, this allows us to obtain the equilibrium coverage and change in conductance as a function of the partial pressure of the "target" molecule in a background of atmospheric air. Specifically, we show how Ni and Cu doped metallic (6,6) SWNTs may work as effective multifunctional sensors for both CO and NH_{3}. In this way, the scheme presented allows one to obtain macroscopic device characteristics and performance data for nanoscale (in this case SWNT) based devices.

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Duncan J. Mowbray, Juan María García-Lastra, Iker Larraza Arocena, Ángel Rubio, Kristian S. Thygesen, Karsten W. Jacobsen. 2011-12-05. Computational design of chemical nanosensors: Transition metal doped single-walled carbon nanotubes. https://arxiv.org/abs/1112.1052

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