Table of Contents Author Guidelines Submit a Manuscript
Journal of Sensors
Volume 2016, Article ID 4319498, 10 pages
Research Article

Temperature Dependence of Sensors Based on Silver-Decorated Nitrogen-Doped Multiwalled Carbon Nanotubes

1Department of Physics, Umeå University, 90187 Umeå, Sweden
2Department of Chemistry, Umeå University, 90187 Umeå, Sweden
3Advanced Materials Department, IPICYT, Camino a la Presa San José 2055, Colonia Lomas 4a Sección, 78216 San Luis Potosí, SLP, Mexico
4Instituto Tecnológico Superior de Irapuato, Carretera Irapuato-Silao Km. 12.5 Colonia El Copal, 36821 Irapuato, GTO, Mexico
5Centro de Nanociencias y Micro y Nanotecnologías, Instituto Politécnico Nacional, Luis Enrique Erro S/N, Colonia Zacatenco, 07738 Delegación Gustavo A. Madero, DF, Mexico
6Institute of Carbon Science and Technology, Shinshu University, 4-17-1 Wakasato, Nagano 380-8553, Japan
7Department of Physics, Applied Physics and Astronomy, Rensselaer Polytechnic Institute, Troy, NY 12180, USA
8Faculty of Engineering, Shinshu University, 4-17-1 Wakasato, Nagano 380-8553, Japan
9Department of Physics, Department of Materials Science and Engineering and Materials Research Institute, The Pennsylvania State University, 104 Davey Lab., University Park, PA 16802-6300, USA

Received 6 August 2015; Accepted 8 December 2015

Academic Editor: Banshi D. Gupta

Copyright © 2016 Eduardo Gracia-Espino et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


Vapor sensors are easily fabricated onto alumina substrates using foils of silver-decorated nitrogen-doped multiwalled carbon nanotubes (CNX-MWNTs-Ag) as active sensing material. The vapor sensors are tested using carbon disulfide, acetone, ethanol, and chloroform vapors. The CNX-MWNTs are produced by chemical vapor deposition process and then decorated with 14 nm Ag nanoparticles (Ag-NPs). The samples are characterized using scanning electron microscopy, transmission electron microscopy, and X-ray diffraction. Our results demonstrate that Ag-decorated CNX-MWNTs exhibit a better response and sensitivity when compared with pristine CNX-MWNTs based sensors, making them promising candidates for air-pollutants environmental monitoring. The temperature effect on the sensor performance is also studied; we found that the detection mechanism could be tuned from physisorption, at room temperature, to chemisorption at higher working temperature. Finally, first-principles density functional calculations are carried out to understand the interactions between the systems involved in the sensors, finding good agreement between experimental results and the theoretical approach.