A Robust Electrochemical CO2 Sensor Utilizing Room Temperature Ionic Liquids

Abstract

Next generation CO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> gas sensors require an enhancement of sensitivity and invariance with regards to CO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> detection and environmental factors. For this study, we report and discuss the effective application of room temperature ionic liquids (RTILs) toward the development of a stable electrochemical CO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> sensor that provides increased valuation toward commercial applications. We have investigated two RTILs on both gold and carbon paste electrodes on printed circuit boards over four different CO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> concentrations. We also have investigated another RTIL on a gold electrode for initial repeatability effects at two CO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> concentrations. Using electrochemical impedance spectroscopy and chronoamperometry, we compare and contrast the initial response behaviors for these RTILs for these sensors. This analysis has aided in the identification of robust combinations of RTIL/electrode toward environmental CO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> sensors.