High-Performance Porous PDMS-Based Piezoresistive Sensor Prepared by a Modified Microwave Irradiation Process

The flexible pressure sensor based on a porous structure has excellent sensing performance. It is critical to develop a large-scale and low-cost manufacturing method for realizing high-performance flexible sensors with porous structures. Herein, a porous polydimethylsiloxane (PDMS) was prepared by a modified microwave irradiation process, and an ultrahigh sensitive flexible piezoresistive sensor with wide sensing range was obtained by coating carbon nanotubes (CNTs)/graphene on the porous PDMS surface. Due to the uniform macroporous structure in PDMS and the synergistic conductive effect of graphene and CNTs, the sensitivity of the flexible sensor is up to 300.31 kPa–1 in 0–50 kPa and 52.51 kPa–1 in 50–200 kPa. Moreover, the flexible device has good reversibility, rapid response speed, good stability, and a certain anti-electromagnetic interference ability. The application in the monitoring of physiological signals demonstrates that the porous PDMS-based sensor prepared by the convenient and environmental microwave irradiation process has remarkable ability in monitoring human health. In addition, the modified microwave irradiation method also provides a way for the preparation of porous materials for other applications such as electromagnetic shielding materials.