Fabrication of a miniaturized room temperature ionic liquid gas sensor for human health and safety monitoring

The growing potential impact of airborne pollutants on human health and safety has escalated the demand for sensors to monitor hazardous gases. Room temperature ionic liquid (RTIL) gas sensors utilizing electrochemical instrumentation demonstrate promising sensitivity, selectivity, and miniaturization capabilities. This paper introduces a microfabrication process that enables miniaturized, rapid response, gas sensors to be realized using RTIL interfaces on a permeable membrane substrate with planar microfabricated electrodes. An RTIL sensor with a 2mm×2mm sensing area is described, and measured responses to methane, a dangerous residential and occupational gas, and sulfur dioxide, a common environmental pollutant, are shown. The reported sensor structure and fabrication process enable realization of sensor arrays for multi-gas monitoring in a low power, miniaturized, wearable system platform.