title: Highly Sensitive Capacitive Gas Sensing at Ionic Liquid-Electrode Interfaces.
abstract: We have developed an ultrasensitive gas-detection method based on the measurement of a differential capacitance of electrified ionic liquid (IL) electrode interfaces in the presence and absence of adsorbed gas molecules. The observed change of differential capacitance has a local maximum at a certain potential that is unique for each type of gas, and its amplitude is related to the concentration of the gas molecules. We establish and validate this gas-sensing method by characterizing SO2 detection at ppb levels with less than 1.8% signal from other interfering species (i.e., CO2, O2, NO2, NO, SO2, H2O, H2, and cyclohexane, tested at the same concentration as SO2). This study opens a new avenue of utilizing tunable electrified IL-electrode interfaces for selective sensing of molecules with a kinetic size resolution of 0.1 Å.
authors.affiliation: Department of Chemistry, Oakland University , Rochester, Michigan 48309, United States.
authors.forename: Zhe
authors.initials: Z
authors.lastname: Wang
authors.affiliation: Department of Chemistry, Oakland University , Rochester, Michigan 48309, United States.
authors.forename: Min
authors.initials: M
authors.lastname: Guo
authors.affiliation: Department of Electrical & Computer Engineering, Michigan State University , East Lansing, Michigan 48824, United States.
authors.forename: Xiaoyi
authors.initials: X
authors.lastname: Mu
authors.forename: Soumyo
authors.initials: S
authors.lastname: Sen
authors.forename: Thomas
authors.initials: T
authors.lastname: Insley
authors.affiliation: Department of Electrical & Computer Engineering, Michigan State University , East Lansing, Michigan 48824, United States.
authors.forename: Andrew J
authors.initials: AJ
authors.lastname: Mason
authors.forename: Petr
authors.initials: P
authors.lastname: Král
authors.affiliation: Department of Chemistry, Oakland University , Rochester, Michigan 48309, United States.
authors.forename: Xiangqun
authors.initials: X
authors.lastname: Zeng
mesh_terms: D002245:Carbon Dioxide / Q000032:analysis; D003510:Cyclohexanes / Q000032:analysis; D004566:Electrodes; D005740:Gases / Q000032:analysis*; D006859:Hydrogen / Q000032:analysis; D052578:Ionic Liquids / Q000737:chemistry*; D007700:Kinetics; D009569:Nitric Oxide / Q000032:analysis; D009585:Nitrogen Dioxide / Q000032:analysis; D010100:Oxygen / Q000032:analysis; D013458:Sulfur Dioxide / Q000032:analysis; D014867:Water / Q000032:analysis
chemical_list: D003510:Cyclohexanes; D005740:Gases; D052578:Ionic Liquids; D014867:Water; D013458:Sulfur Dioxide; D002245:Carbon Dioxide; D009569:Nitric Oxide; C506365:Cyclohexane; D006859:Hydrogen; D009585:Nitrogen Dioxide; D010100:Oxygen