A simple theoretical approach to designing nanotube-based sensors

• Published in: Physica Status Solidi (b) Vol. 248; no. 3; pp. 686 - 693
• Main Authors: Rocha, C. G., Ferreira, M. S.
• Format: Journal Article
• Language: English
• Published: Berlin WILEY-VCH Verlag 01-03-2011; WILEY‐VCH Verlag; Wiley-VCH
• Subjects: carbon nanotubes; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Devices; Electronic structure and electrical properties of surfaces, interfaces, thin films and low-dimensional structures; Electronic structure of nanoscale materials : clusters, nanoparticles, nanotubes, and nanocrystals; Exact sciences and technology; Formalism; Green functions; Guidelines; Impurities; Nanocomposites; Nanomaterials; Nanostructure; Physics; Sensors; Electrical conductivity; Inverse problems; Nanotube devices; Impurities; Measurement sensor; Doping; Nanotubes; Modelling; Electronic density of states; Optimization
• ISSN: 0370-1972; 1521-3951; 1521-3951
• DOI: 10.1002/pssb.201046015

Nanotube‐based sensors are high‐sensitivity devices that can probe a number of nano‐sized impurities through doping‐induced variations in their conductivity. One key question for designing efficient sensors is to establish which impurity/nanotube combination will generate maximum sensitivity. Standard ways for selecting a good nanotube/impurity combination consists of an ad hoc approach that involves sifting through an immense universe of possibilities. This trial‐and‐error approach, despite being time‐consuming and computationally demanding, does not necessarily result in sensitivity optimization. A mathematically transparent theoretical formalism was adopted to introduce an inverse way of thinking about the nanotube/impurity combination by establishing a set of characteristics these components must have to generate high sensitivity devices. In this way guidelines were generated that can narrow the search for the ideal components of nanotube‐based sensors. We illustrate this method with a few examples of nanotubes doped with a different single‐atom impurities.