Ionic-Activated Chemiresistive Gas Sensors for Room-Temperature Operation
Young Geun Song1,2, Young-Seok Shim3, Jun Min Suh4
1Center for Electronic Materials, Korea Institute of Science and Technology (KIST), Seoul, 02792, Republic of Korea.
Small (Weinheim an Der Bergstrasse, Germany)
|August 6, 2019
Summary
A novel ionic-activated sensing mechanism enables high-performance room temperature gas sensors. This approach overcomes limitations of conventional sensors, achieving highly sensitive nitrogen dioxide (NO2) detection under humid conditions.
Area of Science:
- Materials Science
- Chemical Engineering
- Sensor Technology
Background:
- High-performance gas sensors operating at room temperature are highly sought after.
- Conventional chemiresistive sensors face limitations at room temperature due to insufficient reaction energy.
Purpose of the Study:
- To report a novel ionic-activated sensing mechanism for room temperature gas sensors.
- To investigate the development of a hydroxide layer on SnO2 surfaces for enhanced gas detection.
Main Methods:
- Applied voltages on SnO2 surfaces in the presence of humidity to form a hydroxide layer.
- Investigated the ionic-activated sensing mechanism involving ionic conduction and gas reaction.
- Evaluated sensor performance for nitrogen dioxide (NO2) detection at room temperature.
Main Results:
- A hydroxide layer formed on the SnO2 surface, increasing electrical conductivity.
- Achieved sub-parts-per-trillion (132.3 ppt) detection limit for NO2.
- Demonstrated fast recovery time (25.7 s) for 5 ppm NO2 under humid conditions.
Conclusions:
- The ionic-activated sensing mechanism offers a promising pathway for effective room temperature gas sensing.
- This approach overcomes the energy limitations of traditional sensors.
- The developed gas sensor exhibits ideal sensing behavior for NO2 detection.
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