Description:
This
invention employs ionic liquid (IL) films, which are non-volatile and capable of
concentrating gases for subsequent detection. The invention includes multiple
electrodes that can be modified with different IL compositions to enhance the
selectivity of the sensor. In addition, simultaneous sensing can be carried out
with two orthogonal methods to provide additional selectivity to the sensor and
significantly increase the accuracy of the detection at little or no added power
cost. This multi-dimensional sensing takes advantage of the unique properties of
IL to realize both the electrolyte for electrochemical detection (e.g.,
amperometric) and the sorption material for piezoelectric quartz crystal
microbalance detection, enabling a single gas sensor with enhanced sensitivity,
specificity, and stability.
Benefits
* Greater measurement confidence:
Increased selectivity reduces false positives (i.e., false alarm from gases that
were not the target) and false negatives (i.e., no alarm when targeted gases are
present).
* Longer shelf life: IL films have
very low vapor pressures and do not degrade over time.
* Longer operational life: IL films
are effectively inert under operational conditions and can be regenerated with
high heat.
* More
reliable in high temperature operation: Compared to IL-based sensors,
conventional metal oxide sensors lose sensitivity at high temperatures because
their resistance changes nonlinearly in the presence of organic vapors, CO, and
hydrogen gas.
Applications
*
Flammable gas sensors for ambient air monitoring, occupational health and
safety, biomedical diagnostics, industrial process control, and military and
civilian counter-terrorism.
*
Hazardous gas sensors to detect methane gas for safety monitoring.
*
Explosives detectors for sensing the vapor phase of TNT and dinitrotoluene (DNT)
in ppm and ppb concentrations, respectively.
* Organic
volatile sensors to detect organics on toys, clothing, carpet, paints, and so
on.
* High
temperature sensors for identifying emissions within exhaust gases in
high-polluting vehicles.
IP Protection
Status
Patent
pending
