Exploiting Water-Mediated Ethanol Sensing by Polycrystalline ZnO at Room Temperature

Poduska, Kristin M. and Cheng, Jiqai and Rasheed, Muhammad Asim (2012) Exploiting Water-Mediated Ethanol Sensing by Polycrystalline ZnO at Room Temperature. ECS Journal of Solid State Science and Technology, 2 (1). Q23-Q26. ISSN 2162-8777

[img] [English] PDF (Migrated (PDF/A Conversion) from original format: (application/pdf)) - Published Version
Available under License Creative Commons Attribution Non-commercial Share Alike.

Download (994Kb)

Abstract

Ambient moisture can dramatically promote the response of ZnO to ethanol vapor, a hydrophilic gas. By comparing sensor responses in a broad range of humidities, we show that there is a consistent enhancement in ethanol adsorption on ZnO when physisorbed water, detected by capacitance measurements, is present. The time constants related to the capacitive signal recovery during desorption are consistent with the formation of C2H5OH-(H2O)n clusters that have a different desorption rate than water alone. These room temperature results indicate that surface water mediates the dynamic adsorption/re-evaporation equilibrium of solvated ethanol molecules. Thus, attention to interactions between the target gas molecules and their environment is important for understanding the mechanisms behind selective gas sensing.

Item Type: Article
URI: http://research.library.mun.ca/id/eprint/6214
Item ID: 6214
Department(s): Science, Faculty of > Physics and Physical Oceanography
Date: 16 November 2012
Date Type: Publication
Related URLs:

Actions (login required)

View Item View Item

Downloads

Downloads per month over the past year

View more statistics