MXene-Sponge Based High-Performance Piezoresistive Sensor for Wearable Biomonitoring and Real-Time Tactile Sensing.

Area of Science:

• Materials Science
• Nanotechnology
• Wearable Electronics

Background:

• Traditional electrode microfabrication for wearables is costly and complex.
• Existing methods often generate significant waste discharge.
• Need for efficient, cost-effective electrode fabrication for advanced sensors.

Purpose of the Study:

• To develop a novel, cost-effective electrode microfabrication technique using helium plasma irradiation.
• To engineer a flexible piezoresistive pressure sensor with enhanced performance.
• To explore the sensor's application in wearable biomonitoring and health assessment.

Main Methods:

• Helium plasma irradiation to create microstructured molybdenum electrodes.
• Fabrication of a flexible pressure sensor using a Ti3C2Tx nanosheet-immersed polyurethane sponge.
• Characterization of sensor performance, including sensitivity, linearity, and response time.
• Finite element simulation to analyze structural effects on performance.

Main Results:

• Achieved high sensitivity (1.52 kPa⁻¹) and good linearity (r² = 0.9985) over a wide sensing range (0-100 kPa).
• Demonstrated a fast response time of 226 ms for pressure detection.
• Confirmed the crucial role of hierarchical structures (pore size, plasma bias, MXene concentration) in performance enhancement.
• Successfully applied the sensor for radial pulse measurement, gesture detection, and object identification.

Conclusions:

• Helium plasma irradiation offers a viable, eco-friendly alternative for microstructured electrode fabrication.
• The developed flexible pressure sensor exhibits excellent performance for diverse wearable applications.
• The sensor shows significant potential for non-invasive biomonitoring and health assessment.