Research Seminar Abstract
With the move toward citizen science to aid in monitoring air quality, the need for portable, robust, and inexpensive gas sensors has driven work into fabricating novel devices. Tin(IV) oxide (SnO2) nanomaterials are useful for solid-state gas sensors because they can detect a wide range of gases and have a relatively low manufacturing cost. Combining this material with a paper substrate has the added benefit of increasing the flexibility of the device and increasing the amount of accessible SnO2 while maintaining overall sensor size. The required operating temperature of SnO2 (≥300 °C), however, limits the combining of these materials and widespread commercialization of these devices. Plasma processing, therefore, is a promising strategy to address this issue and enhance gas sensor performance (i.e. selectivity and response and recovery time) by modifying the surface while maintaining desirable bulk properties.
This presentation will focus on the Ar/O2 plasma modification of SnO2 nanoparticle paper gas sensors (PGS) as a function of various plasma operating parameters. Compared to the untreated nanoparticles on a traditional substrate (i.e., ZrO2), plasma treated PGS demonstrated an increase in response to carbon dioxide, ethanol, and benzene at ≤100 °C. Response and recovery studies also showed improved gas sensing behavior to ethanol after plasma treatment at operating temperatures around room temperature. Along with gas sensing studies, optical emission spectroscopy data from the gas-phase of the plasma will be presented as a means of working toward ultimately elucidating the relationship between material surface chemistry and sensor performance. Finally, some preliminary results on the applicability of this fabrication method to other gas sensing materials will be discussed.