Next Article in Journal
Next Article in Special Issue
Previous Article in Journal
Previous Article in Special Issue
Nanomaterials 2013, 3(3), 469-485; doi:10.3390/nano3030469
Article

Nanostructure-Directed Chemical Sensing: The IHSAB Principle and the Effect of Nitrogen and Sulfur Functionalization on Metal Oxide Decorated Interface Response

1
 and 1,2,*
Received: 27 June 2013; in revised form: 26 July 2013 / Accepted: 29 July 2013 / Published: 7 August 2013
(This article belongs to the Special Issue Nanomaterials in Sensors)
View Full-Text   |   Download PDF [381 KB, uploaded 7 August 2013]
Abstract: The response matrix, as metal oxide nanostructure decorated n-type semiconductor interfaces are modified in situ through direct amination and through treatment with organic sulfides and thiols, is demonstrated. Nanostructured TiO2, SnOx, NiO and CuxO (x = 1,2), in order of decreasing Lewis acidity, are deposited to a porous silicon interface to direct a dominant electron transduction process for reversible chemical sensing in the absence of significant chemical bond formation. The metal oxide sensing sites can be modified to decrease their Lewis acidity in a process appearing to substitute nitrogen or sulfur, providing a weak interaction to form the oxynitrides and oxysulfides. Treatment with triethylamine and diethyl sulfide decreases the Lewis acidity of the metal oxide sites. Treatment with acidic ethane thiol modifies the sensor response in an opposite sense, suggesting that there are thiol (SH) groups present on the surface that provide a Brønsted acidity to the surface. The in situ modification of the metal oxides deposited to the interface changes the reversible interaction with the analytes, NH3 and NO. The observed change for either the more basic oxynitrides or oxysulfides or the apparent Brønsted acid sites produced from the interaction of the thiols do not represent a simple increase in surface basicity or acidity, but appear to involve a change in molecular electronic structure, which is well explained using the recently developed inverse hard and soft acids and bases (IHSAB) model.
Keywords: nanostructure directed sensing; nitrogen and sulfur functionalization nanostructure directed sensing; nitrogen and sulfur functionalization
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.

Export to BibTeX |
EndNote


MDPI and ACS Style

Laminack, W.I.; Gole, J.L. Nanostructure-Directed Chemical Sensing: The IHSAB Principle and the Effect of Nitrogen and Sulfur Functionalization on Metal Oxide Decorated Interface Response. Nanomaterials 2013, 3, 469-485.

AMA Style

Laminack WI, Gole JL. Nanostructure-Directed Chemical Sensing: The IHSAB Principle and the Effect of Nitrogen and Sulfur Functionalization on Metal Oxide Decorated Interface Response. Nanomaterials. 2013; 3(3):469-485.

Chicago/Turabian Style

Laminack, William I.; Gole, James L. 2013. "Nanostructure-Directed Chemical Sensing: The IHSAB Principle and the Effect of Nitrogen and Sulfur Functionalization on Metal Oxide Decorated Interface Response." Nanomaterials 3, no. 3: 469-485.


Nanomaterials EISSN 2079-4991 Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert