Western Kentucky University
Department of Physics and Astronomy

Colloquium

Vladimir Dobrokhotov

Department of Physics and Astronomy
Western Kentucky University

"Hybrid Nanostructures for Detection of Explosive Materials"

September 21, 2009 @ 4:00 in TCCW 251

coffee at 3:30 in TCCW 368

Abstract

The ability to sense the environment is of critical importance for a broad array of applications ranging from ecosystem health, hazardous materials avoidance/chemical warfare to medical applications. We are investigating the use of self-assembled monolayer (SAM)-functionalized nanoparticle-decorated nanosprings as a novel design for sensing vapors associated with explosives. This research is based on a fundamentally new concept of sensing by hybrid 3-D nanostructures that will contribute to our abilities to create reliable sensors for detection of vapors associated with explosives. The common requirements for any sensor application are sensitivity, selectivity, refreshability, repeatability, low cost of manufacture, and ease of use. The project goal is to answer these needs through the use of mats of functionalized metal nanoparticle-coated nanosprings as a novel type of low-cost nanomaterials-based gas sensor. Preliminary experiments have shown a significant change in the electrical properties of gold nanoparticle coated semiconductor nanowires when they are exposed to various gases. The advantage of this approach is that very dilute quantities of airborne explosive products can be accumulated over a few seconds to a few minutes onto our high surface area nanospring electrodes. This will facilitate electronic detection, which in contrast to optical detection methods reduces false positive signals, reduces detector sizes and complexity.