Hostname: page-component-78c5997874-m6dg7 Total loading time: 0 Render date: 2024-11-14T05:14:08.818Z Has data issue: false hasContentIssue false

Gas Sensing with Gold Nanoparticle-Decorated GaN Nanowire Mats

Published online by Cambridge University Press:  01 February 2011

Vladimir Dobrokhotov
Affiliation:
dobr2610@uidaho.eduUniversity of IdahoDepartment of PhysicsMoscow ID 83844-0903United States
David McIlroy
Affiliation:
dmcilroy@uidaho.edu, University of Idaho, Department of Physics, Moscow, ID, 83844-0903, United States
Chris Berven
Affiliation:
berven@uidaho.edu, University of Idaho, Department of Physics, Moscow, ID, 83844-0903, United States
Get access

Abstract

The electrical properties of chemical sensors constructed from mats of bare GaN nanowires and GaN nanowires decorated with gold nanoparticles are presented. The sensors were tested in vacuum and at atmospheric pressures of Ar, N2 and methane. The current-voltage (I-V) curves of the sensor constructed with bare GaN nanowires were Ohmic and the device was insensitive to all gases tested. The I-V curves of the sensor constructed from GaN decorated with Au nanoparticles were non-linear and exhibited a drop in conductivity of five orders of magnitude relative to bare GaN nanowire sensors. The Au nanoparticle decorated nanowires also exhibited electrical responses that were chemically selective. The sensor exhibited a nominal response to Ar and a slightly greater response to N2 relative to vacuum. A suppression of the conductivity of the Au-GaN device of 50% was observed upon exposure to methane. Both the drop in conductivity of the Au-GaN nanowire-based sensor, relative to bare GaN nanowires, and the response to methane are explained in terms of the formation of a depletion layer and an increase in the depletion layer width due to physisorption induced surface potentials.

Type
Research Article
Copyright
Copyright © Materials Research Society 2006

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

1 LaLonde, A.D., Norton, M.G., Zhang, D., Gangadean, D., Alkhateeb, A., Padmanabhan, R. and McIlroy, D.N., J. Mat. Res. 20 3021 (2005)Google Scholar
2 Kim, J., So, H., Park, J., Kim, J., Kim, J., Lee, C., and Lyu, S., Applied Physics Letters 80 3548 (2002)Google Scholar
3 Haruta, M., Applied Catalysis A: General 222 427 (2001)Google Scholar
4 Haruta, M., The Chemical Record 3 75 (2003)Google Scholar
5 Puckett, S. D., Heuser, J. A., Keith, J. D., Spendel, W. U., and Pacey, G. E., Talanta 66 1242 (2005)Google Scholar
6 Yu, A., Liang, Z., Cho, J., and Caruso, F., Nano Letters 3 1203 (2003)Google Scholar
7 Geng, J., Thomas, M., Shephard, D., and Johnson, B., Chem. Commun. 14 1895 (2005)Google Scholar
8 Kolmakov, A., Klenov, D.O., Lilach, Y., Stemmer, S., and Moskovits, M., Nano Letters 5 667 (2005)Google Scholar
9 Colinge, J.P., Colinge, C.A., Physics of Semiconductor Devices, Kluwer Academic Publishers (2002)Google Scholar
10 Semiconductors – Basic Data, edited by Madelung, O., Springer (1996)Google Scholar
11 Prutton, M., Introduction to Surface Science, Oxford Science Publications (1994)Google Scholar