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Updated: Jun 13, 2025
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Strain Sensing Based on Multiscale Composite Materials Reinforced with Graphene Nanoplatelets
Published on: November 7, 2016
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Sensing with Thermally Reduced Graphene Oxide under Repeated Large Multi-Directional Strain
Armin Yazdi1, Li-Chih Tsai2, Nathan P Salowitz3
1Department of Civil and Environmental Engineering, University of Wisconsin Milwaukee, Milwaukee, WI 53211, USA.
Sensors (Basel, Switzerland)
|September 14, 2024
Summary
Thermally reduced graphene oxide (rGO) demonstrates high sensitivity as a strain sensor, maintaining electromechanical integrity under large strains. Its non-linear behavior at high strains and consistent cyclic response show promise for advanced sensing applications.
Area of Science:
- Materials Science
- Nanotechnology
- Electrical Engineering
Background:
- Strain sensing is crucial for monitoring mechanical stimuli.
- Graphene oxide (GO) and its reduced form (rGO) offer potential for high-performance sensors due to their unique properties.
- rGO can be synthesized from abundant materials and exhibits high sensitivity with reported gauge factors up to 200.
Purpose of the Study:
- To investigate the electromechanical behavior of thermally reduced graphene oxide (rGO) as a strain sensor.
- To evaluate the sensor's performance under repeated large mechanical strains (up to 20.72%).
- To analyze the electrical signal output in multiple directions relative to the applied strain.
Main Methods:
- Macroscopic rGO-strain sensors were fabricated by depositing graphene oxide flakes onto Polydimethylsiloxane (PDMS) substrates and thermally reducing them.
- Sensors underwent cyclic tensile testing to assess electromechanical response under varying strain levels.
- Electrical resistance was measured parallel to the direction of applied tension (x^).
Main Results:
- Electrical resistance showed linear behavior up to approximately 7.5% strain, transitioning to non-linear behavior at higher strains.
- A linear fit across the investigated strain range yielded a gauge factor of 91.50 (Ω/Ω)/(m/m).
- Cyclic testing indicated the presence of residual micro-cracks after the first loading cycle, with high consistency in electromechanical response observed from the second cycle onwards.
Conclusions:
- Thermally reduced graphene oxide (rGO) functions as a sensitive strain sensor capable of withstanding large strains.
- The sensor exhibits distinct linear and non-linear electromechanical responses depending on the strain magnitude.
- The study highlights the potential of rGO-based sensors for applications requiring robust and sensitive strain detection, with consistent performance observed over multiple cycles.
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