Gas Sensing With Mats of Gold-Nanoparticle Decorated GaN Nanowires

Author

Berven, Chris A. ; Dobrokhotov, Vladimir ; McIlroy, David N. ; Chava, Sirisha ; Abdelrahaman, Ramey ; Heieren, Abby ; Dick, Joseph ; Barredo, Wilson

Author_Institution

Dept. of Phys., Idaho Univ., Moscow, ID

Volume

8

Issue

6

fYear

2008

fDate

6/1/2008 12:00:00 AM

Firstpage

930

Lastpage

935

Abstract

We report on the use of mats of gold nanoparticle decorated GaN nanowires as gas sensors. The sensing was by the repeated and reversible measurement of changes in the current-voltage characteristics of the mat of nanowires. The nanowires had diameters of about 200 nm and were many microns long. The mat was grown on a 1-cm diameter sapphire disk and was about 10 thick. The selectivity mechanism is attributed to the details of the surface morphology of the gold nanoparticles decorating the surface of the nanowires. The changes in the currents are attributed to a depletion mechanism in the nanowires due to the formation of a Schottky barrier due to the presence of the gold on the inherently n-type GaN. We were able to detect CO, CH₄, CO₂, H₂, and observed possible evidence of creation of the by-products of the water-gas shift reaction.

Keywords

III-V semiconductors; Schottky barriers; gallium compounds; gas sensors; gold; nanoparticles; nanowires; surface morphology; wide band gap semiconductors; Au-GaN; Schottky barrier formation; current-voltage characteristics; depletion mechanism; gas sensing; gold-nanoparticles; nanowires; sapphire disk; selectivity mechanism; surface morphology; Current measurement; Gallium nitride; Gas detectors; Gold; Nanomaterials; Nanoparticles; Nanowires; Optical sensors; Physics; Surface morphology; Detectors; nanoparticles; nanotechnology; nanowires;

fLanguage

English

Journal_Title

Sensors Journal, IEEE

Publisher

ieee

ISSN

1530-437X

Type

jour

DOI

10.1109/JSEN.2008.923181

Filename

4529168