A Novel Porous PDMS-AgNWs-PDMS (PAP)-Sponge-Based Capacitive Pressure Sensor

Area of Science:

• Materials Science
• Nanotechnology
• Sensor Technology

Background:

• Flexible electronics and wearable devices require cost-effective, highly sensitive pressure sensors.
• Existing sensors often face limitations in fabrication ease, sensitivity, or flexibility.

Purpose of the Study:

• To develop a highly sensitive and flexible capacitive pressure sensor using a novel porous dielectric layer.
• To optimize sensor performance by varying silver nanowire (AgNW) loading.

Main Methods:

• Fabrication of a porous polydimethylsiloxane (PDMS) sponge infused with silver nanowires (AgNWs) using sucrose as a template.
• Assembly of the sensor by sandwiching the porous PAP sponge dielectric layer between copper electrodes.
• Optimization of AgNW loading to enhance sensor sensitivity.

Main Results:

• The optimized sensor achieved a high sensitivity of 0.62 kPa⁻¹ in the 0-1 kPa range with 150 mg AgNW loading.
• The PAP sponge exhibited excellent mechanical properties (1.425 MPa tensile strength, 156.38% elongation) and a specific surface area of 2.0 cm²/g.
• The sensor demonstrated waterproof performance, high elasticity, low hysteresis, light weight, and low density.

Conclusions:

• A novel, highly sensitive, and flexible capacitive pressure sensor based on a porous PAP sponge has been successfully fabricated.
• The sensor's performance is significantly enhanced by incorporating AgNWs, showing great potential for wearable electronic applications.
• The developed sensor exhibits desirable properties including excellent mechanical strength, waterproof capability, and low hysteresis.