Hydrogen gas is a common byproduct in industrial and chemical processes. It is also frequently used in transportation applications such as fuel cell vehicles. It has no smell and no taste, but it may pose immediate safety risks because it is combustible in air. Multi-modal hydrogen sensors are developed by depositing nanofibers on quartz tuning forks (QTF). Near field electrospinning (NFES) was used to produce flexible, semi-conductive nanofibers that can be integrated into electronic systems as environmental gas sensors. The electrospinning parameters, especially tip-to-collector distance, were optimized to increase sensor performance. Treated multi-walled carbon nanotubes, camphorsulfonic acid doped polyaniline and platinum nanoparticles were used as the sensing materials with polyethylene oxide being used as an electrospinning guide. Intense pulsed light and sputter coating were used to maximize adhesion of the fibers onto the devices. The QTF sensor combines mechanical and electrochemical sensing methodologies. Changes in the resonance frequency were used to determine gas adsorption. Changes in the electrical resistance were used to determine the gas properties. As a result, the sensors were selective to hydrogen versus other gases and vapors including methane, hexane, toluene, ammonia, ethanol and carbon dioxide. Furthermore, the sensors can detect ppm levels of hydrogen even in the presence of high humidity.
Conference Committee Involvement (2)
Nano-, Bio-, Info-Tech Sensors and 3D Systems
27 April 2020 | Anaheim, California, United States