3D-Printed Graphene Nanoplatelets/Polymer Foams for Low/Medium-Pressure Sensors

Area of Science:

• Materials Science
• Nanotechnology
• Biomedical Engineering

Background:

• Growing demand for wearable devices in health monitoring and motion detection.
• Need for novel, cost-effective, and highly sensitive flexible sensors.

Purpose of the Study:

• To develop innovative piezoresistive pressure sensors using 3D printed porous flexible foams.
• To investigate the effect of foam structure and graphene nanoplatelet (GNP) concentration on sensor performance.

Main Methods:

• Fabrication of grid and triply periodic minimal surface foams via 3D printing and polymer infiltration.
• Coating foam pores with graphene nanoplatelets (GNPs) at varying concentrations.
• Morphological analysis using field emission scanning electron microscopy (FE-SEM).
• Mechanical and piezoresistive characterization through quasi-static uniaxial compression tests.

Main Results:

• Optimized grid-based foam sensors using Solaris polymer exhibited superior sensitivity.
• Achieved maximum sensitivity of 0.088 kPa⁻¹ below 10 kPa, increasing to 0.24 kPa⁻¹ at 80 kPa.
• Successfully demonstrated sensor application in measuring heartbeats within the 10-20 kPa range.

Conclusions:

• 3D printed porous foams offer a promising platform for developing sensitive flexible piezoresistive pressure sensors.
• The developed sensors are suitable for wearable health monitoring, particularly for detecting physiological signals like heartbeats.