Title: Vapor Sensing Using Conjugated Molecule-Linked Au Nanoparticles in a Silica Matrix

Abstract

Cross-linked assemblies of nanoparticles are of great value as chemiresistor-type sensors. Herein, we report a simple method to fabricate a chemiresistor-type sensor that minimizes the swelling transduction mechanism while optimizing the change in dielectric response. Sensors prepared with this methodology showed enhanced chemoselectivity for phosphonates which are useful surrogates for chemical weapons. Chemoselective sensors were fabricated using an aqueous solution of gold nanoparticles that were then cross-linked in the presence of the silica precursor, tetraethyl orthosilicate with the $\alpha$ -, $\omega$ -dithiolate (which is derived from the in situ deprotection of 1,4-di(Phenylethynyl- $4^{\prime }$ , $4^{″}$ -diacetylthio)-benzene ( 1 ) with wet triethylamine). The cross-linked nanoparticles and silica matrix were drop coated onto interdigitated electrodes having 8  $\mu$ m spacing. Samples were exposed to a series of analytes including dimethyl methylphosphonate (DMMP), octane, and toluene. A limit of detection was obtained for each analyte. Sensors assembled in this fashion were more sensitive to dimethyl methylphosphonate than to octane by a factor of 1000.

Authors:

Dirk, Shawn M. ^[1]; Howell, Stephen W. ^[2]; Price, B. Katherine ^[3]; Fan, Hongyou ^[4]; Washburn, Cody ^[1]; Wheeler, David R. ^[5]; Tour, James M. ^[3]; Whiting, Joshua ^[6]; Simonson, R. Joseph ^[6]

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+ Show Author Affiliations

1. Organic Materials Department, Sandia National Laboratories, MS-0892, Albuquerque, NM 87185, USA
2. Advanced Sensor Technologies Department, Sandia National Laboratories, MS-0892, Albuquerque, NM 87185, USA
3. Departments of Chemistry and Mechanical Engineering and Materials Science, The Smalley Institute for Nanoscale Science and Technology, Rice University, MS-222, 6100, Houston, TX 77005, USA
4. Ceramic Processing and Inorganic Department, Sandia National Laboratories, MS-1349, Albuquerque, NM 87185, USA
5. Biosensors and Nanomaterials Department, Sandia National Laboratories, MS-0892, Albuquerque, NM 87185, USA
6. Micro-Total-Analytical Systems Department, Sandia National Laboratories, MS-0892, Albuquerque, NM 87185, USA

Publication Date:

Thu Jan 01 00:00:00 EST 2009

Sponsoring Org.:

USDOE

OSTI Identifier:

1198237

Grant/Contract Number:  

AC04-94AL8500

Resource Type:

Published Article

Journal Name:

Journal of Nanomaterials

Additional Journal Information:

Journal Name: Journal of Nanomaterials Journal Volume: 2009; Journal ID: ISSN 1687-4110

Publisher:

Hindawi Publishing Corporation

Country of Publication:

Egypt

Language:

English