Ultrafast humidity sensor based on liquid phase exfoliated graphene.
Stevan Andrić1, Tijana Tomašević-Ilić2, Marko V Bošković1
1Center for Microelectronic Technologies, Institute of Chemistry, Technology and Metallurgy, University of Belgrade, Njegoševa 12, 11000, Belgrade, Serbia.
Nanotechnology
|September 17, 2020
Summary
New graphene humidity sensors offer fast, flexible, and transparent solutions for various applications. These sensors enable precise humidity monitoring for medical uses and touchless interactive panels.
Area of Science:
- Materials Science
- Sensor Technology
- Nanotechnology
Background:
- Humidity sensing is crucial across diverse fields, including environmental, industrial, and medical applications.
- Existing humidity sensors often lack thinness, transparency, large-area compatibility, flexibility, or sufficient speed for applications like respiration monitoring.
Purpose of the Study:
- To develop novel chemiresistive graphene-based humidity sensors.
- To achieve sensors with a unique combination of properties: thin, transparent, flexible, large-area compatible, and fast response times.
Main Methods:
- Utilizing facile liquid phase exfoliation of graphene.
- Employing Langmuir-Blodgett assembly for sensor fabrication, enabling large active areas.
- Characterizing sensor performance including resistance change, linearity, selectivity, transparency, and response time.
Main Results:
- Graphene sensors demonstrated resistance changes up to 10% with humidity variations.
- Linear performance was observed across a wide relative humidity (RH) range (8%–95%).
- Sensors exhibited high transparency (nearly 80%), flexibility, and rapid response times of 30 ms, with minimal response to other air constituents.
Conclusions:
- The developed graphene sensors offer a promising solution for humidity sensing with superior performance characteristics.
- The fast response time is suitable for real-time applications such as human respiration monitoring and skin humidity sensing.
- Potential applications include flexible touchless interactive panels and advanced medical monitoring devices.
