Temperature-Immune, Wide-Range Flexible Robust Pressure Sensors for Harsh Environments

Area of Science:

• Materials Science
• Engineering
• Nanotechnology

Background:

• Flexible pressure sensors are crucial for applications in new energy, aerospace, and robotics.
• Existing sensors struggle with reliability in harsh environments (high pressure, variable temperatures) due to mechanical mismatch and instability.

Purpose of the Study:

• To develop a robust flexible piezoresistive pressure sensor with enhanced reliability and environmental resilience.
• To overcome limitations of current sensors operating in demanding conditions.

Main Methods:

• Composite scheme using multiwalled carbon nanotubes (MWCNTs), graphite (GP), and thermoplastic polyurethane (TPU) for a near-zero temperature coefficient of resistance (TCR).
• Radial gradient pressure-dividing microstructure to increase pressure range.
• Flexible interface bonding process with a self-soluble transition layer.

Main Results:

• Optimized sensing layer achieved near-zero TCR between 25-70 °C.
• Radial gradient microstructure increased pressure range to 2 MPa.
• Flexible interface bonding resulted in low signal fluctuations (0.6%) and high interface strength (1200 kPa).

Conclusions:

• The proposed composite scheme significantly improves the robustness and reliability of flexible pressure sensors.
• The sensor demonstrates potential for monitoring physiological signals and environmental resilience in power cells.
• This design offers a new approach for developing pressure sensors for harsh environments.