Summary:
Nitrogen Oxides (NOx) present a host of environmental and health problems, including acid rain, urban smog, acidification of lakes and streams, and damage of forest soils. The major source of NOx is from the combustion of fossil fuels, and NOx sensors are employed in the development of internal combustion engines in order to optimize combustion and minimize emissions. Nitric Oxide is also an important biological molecule and its level in human breath is also an indication of many diseased states, including asthma.
Resistance-based electrochemical NOx sensors, while exhibiting good sensitivity, often react to many different gases, and selectivity suffers. Potentiometric sensors offer a promising approach for NOx measurements in harsh environments, but often suffer from interference with other gases.
Researchers at The Ohio State University have developed a novel potentiometric NOx sensor that overcomes the interference limitations of previous potentiometric sensors. This sensor is extremely selective to NOx in the presence of other gas species, and sensitivities have been confirmed in the parts-per-billion range! The sensor is ideal for incredibly precise NOx measurements in environments as diverse as engines and for breath monitoring.
Potential Applications:
- Medical diagnostics
- Combustion optimization
- Environmental NOx monitoring
Advantages:
- Ridiculously high sensitivity (ppb range!)
- Excellent selectivity
- Will withstand extreme environments
- Cost effective as potentiometric output does not require sophisticated support electronics