A Robust Flexible Electrochemical Gas Sensor Using Room Temperature Ionic Liquid

This paper introduces a robust electrochemical gas sensor featuring room temperature ionic liquid (RTIL) as electrolyte and porous polytetrafluoroethylene as a flexible substrate. Using a planar-electrodes-on-permeable-membrane structure, a flexible RTIL sensor with 9.6 mm
²
sensing area is microfabricated. The sensor's response to oxygen is measured, achieving sensitivity of 0.48 μA/%O
₂
, a linearity of 0.997 R
²
in range of 0%-21% O
₂
, and limit of detection of 0.08% O
₂
. The reported sensor structure and fabrication process enable realization of sensor arrays for multi-gas monitoring in a low power, miniaturized, and wearable system platform.