title: Cross-Selectivity Enhancement of Poly(vinylidene fluoride-hexafluoropropylene)-Based Sensor Arrays for Detecting Acetone and Ethanol.
abstract: Two methods for cross-selectivity enhancement of porous poly(vinylidene fluoride-hexafluoropropylene) (PVDF-HFP)/carbon black (CB) composite-based resistive sensors are provided. The sensors are tested with acetone and ethanol in the presence of humid air. Cross-selectivity is enhanced using two different methods to modify the basic response of the PVDF-HFP/CB sensing platform. In method I, the adsorption properties of PVDF-HFP/CB are altered by adding a polyethylene oxide (PEO) layer or by treating with infrared (IR). In method II, the effects of the interaction of acetone and ethanol are enhanced by adding diethylene carbonate (DEC) or PEO dispersed in DEC (PEO/DEC) to the film. The results suggest the approaches used in method I alter the composite ability to adsorb acetone and ethanol, while in method II, they alter the transduction characteristics of the composite. Using these approaches, sensor relative response to acetone was increased by 89% compared with the PVDF-HFP/CB untreated film, whereas sensor relative response to ethanol could be decreased by 57% or increased by 197%. Not only do these results demonstrate facile methods for increasing sensitivity of PVDF-HFP/CB film, used in parallel they demonstrate a roadmap for enhancing system cross-selectivity that can be applied to separate units on an array. Fabrication methods, experimental procedures and results are presented and discussed.
authors.affiliation: Department of Electrical and Computer Engineering, Indiana University-Purdue University Indianapolis (IUPUI), Indianapolis, IN 46202, USA. alidane@umail.iu.edu.|Integrated Nanosystems Development Institute (INDI), Indiana University-Purdue University Indianapolis (IUPUI), Indianapolis, IN 46202, USA. alidane@umail.iu.edu.
authors.forename: Ali
authors.initials: A
authors.lastname: Daneshkhah
authors.affiliation: Department of Electrical and Computer Engineering, Indiana University-Purdue University Indianapolis (IUPUI), Indianapolis, IN 46202, USA. shrests2@miamioh.edu.|Integrated Nanosystems Development Institute (INDI), Indiana University-Purdue University Indianapolis (IUPUI), Indianapolis, IN 46202, USA. shrests2@miamioh.edu.|Present Address: Department of Electrical and Computer Engineering, College of Engineering and Computing, Miami University, Oxford, OH 45056, USA. shrests2@miamioh.edu.
authors.forename: Sudhir
authors.initials: S
authors.lastname: Shrestha
authors.affiliation: Integrated Nanosystems Development Institute (INDI), Indiana University-Purdue University Indianapolis (IUPUI), Indianapolis, IN 46202, USA. apsiegel@iupui.edu.
authors.forename: Amanda
authors.initials: A
authors.lastname: Siegel
authors.affiliation: Department of Electrical and Computer Engineering, Indiana University-Purdue University Indianapolis (IUPUI), Indianapolis, IN 46202, USA. kvarahra@iupui.edu.|Integrated Nanosystems Development Institute (INDI), Indiana University-Purdue University Indianapolis (IUPUI), Indianapolis, IN 46202, USA. kvarahra@iupui.edu.
authors.forename: Kody
authors.initials: K
authors.lastname: Varahramyan
authors.affiliation: Integrated Nanosystems Development Institute (INDI), Indiana University-Purdue University Indianapolis (IUPUI), Indianapolis, IN 46202, USA. agarwal@iupui.edu.|Department of Mechanical Engineering, Indiana University-Purdue University Indianapolis (IUPUI), Indianapolis, IN 46202, USA. agarwal@iupui.edu.
authors.forename: Mangilal
authors.initials: M
authors.lastname: Agarwal
keywords: PVDF-HFP/carbon black composite; acetone sensor; ethanol sensor; low water sensitivity; volatile organic compounds