Highly Stretchable and Sensitive Strain Sensor Based on Facilely Prepared Three-Dimensional Graphene Foam Composite

Area of Science:

• Materials Science
• Nanotechnology
• Sensor Technology

Background:

• Wearable strain sensors are crucial for human motion detection and biomechanical systems.
• Existing 3D graphene foam (GF) strain sensors face challenges in cost, sensitivity, and stretchability.

Purpose of the Study:

• To develop a highly stretchable and sensitive strain sensor.
• To overcome limitations of previous GF-based strain sensors.

Main Methods:

• Fabrication of a 3D graphene foam (GF) via a scalable assembly process from graphene oxide.
• Composite formation by infiltrating PDMS prepolymer into the GF framework.
• Characterization of the sensor's stretchability, sensitivity (gauge factor), and long-term stability.

Main Results:

• The GF/PDMS composite sensor achieved 30% stretchability.
• A high gauge factor of 98.66 was recorded at 5% strain.
• The sensor demonstrated long-term stability over 200 stretching-relaxing cycles.
• Successful implementation for monitoring elbow and finger bending with reproducible resistance changes.

Conclusions:

• The developed GF/PDMS composite strain sensor offers superior stretchability and sensitivity.
• This technology shows significant potential for biomechanical systems and human-interactive applications.
• The facile and scalable fabrication method makes it suitable for practical use.