Sensors

After we develop novel nanomaterials we attempt to apply them. Several of the applications have resulted in companies bringing new products to market. 

 Ethylene Sensor

Ethylene drives fruit ripening processes and together with carbon dioxide and oxygen is of central interest to postharvest researchers. To achieve more consistent readings from a portable electrochemical gas sensor during use in the field, we have developed a calibration standard that combines ethephon (2-chloroethylphosphonic acid) with a buffering agent to release a constant amount of ethylene gas and an inline polar hydrocarbon trap that can be used to remove interfering compounds. Initial test results of the inline polar hydrocarbon trap can be found in the following pdf CI-900 Interfering Gas Trap Poster V2.pdf.

By combining these methods the accuracy and precision of electrochemical postharvest technologies for respiration studies of fruit can be improved. Our hope is that through partnership with Felix Instruments we can reduce food waste and improve sustainability of precision agriculture. 

In collaboration with CID Bio-Science we investigated the effects of humidity, temperature, and operating voltage on potential electrochemical sensors for use in their products.

Hydrogen Sensor: Palladium Nanoparticles Attached to Carbon Nanotubes

The CNTs were synthesized by the test tube synthetic method were attached with palladium nanoparticles. The composite was applied to detect H2 at very low concentration (ppm).  Different response behaviors of low and high H₂ concentrations were discovered and are under-investigated.  Work of Hoang Tran.

Resistive Chlorine Sensor: n-doped Tin Oxide

Gold contacts are attached with silver paste to a block of Doped SnO₂ powder which was compressed (5,463Kg/cm^-2) and heated (400°C).

 Below is a response curve of the sensor.