Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
10410934 | Sensors and Actuators B: Chemical | 2005 | 12 Pages |
Abstract
A technique for the measurement of ethanol concentrations in aqueous mixtures is reported, in which a permeable membrane is used to transport ethanol vapors to a microelectromechanical (MEMS) chemi-capacitor array. The fixed plate micro-capacitors were filled with a polymeric dielectric material, siloxanefluoro alcohol (SXFA), whose dielectric constant increased upon absorption of ethanol vapor. Measurements of the mixture's liquid-phase concentration were made in the vapor-phase by sampling the saturated vapors through a hydrophobic, vapor permeable nanopore filter. The performance of these sensors was characterized over a range of ethanol/water mixture concentrations and flow cell temperatures. The limit of detection (LOD) for ethanol in water using the capacitive micro-sensors in the present arrangement was found to be 40Â ppm.
Keywords
Related Topics
Physical Sciences and Engineering
Chemistry
Analytical Chemistry
Authors
Dennis L. McCorkle, Robert J. Warmack, Sanjay V. Patel, Todd Mlsna, Scott R. Hunter, Thomas L. Ferrell,