Stress and Magnetic Field Bimode Detection Sensors Based on Flexible CI/CNTs–PDMS Sponges

Abstract

This work reports porous carbonyl iron particles/multiwalled carbon nanotubes-polydimethylsiloxane composites (PCMCs) with high flexibility and low density. In comparison to the solid product, the porous PCMC possesses a larger elongation and deformation. Because of the excellent magnetic-mechanic-electric coupling performance, the flexible composite exhibits bimode sensitivity to both the external stresses and magnetic field. Typically, the normalized resistance variation (Δ R/ R) of PCMC reaches 82.8% and 52.2% when the compression strain and tension strain are 60% and 50%, respectively. Moreover, the Δ R/ R induced by bending, twisting, and magnetostress also changes remarkably. When a 144 mT magnetic field is applied, the Δ R/ R of PCMC increases with 3.6%. To further understand the magnetic-mechanic-electric coupling mechanism, a conductive network sensing model is proposed and analyzed. Finally, on the basis of the bimode PCMC sensor array, a smart chessboard which can precisely discriminate special chesses with different masses and magnets is developed. This study provides a new fabrication method for next-generation three-dimensional smart sensors toward artificial electronics and soft robotics.

E-Skin: The Dawn of a New Era of On-Body Monitoring Systems

“…Furthermore, breaking and rebuilding electrostatic interactions and hydrogen bonds within these materials dissipated induced strain [30]. The most used stretchable polymeric materials for e-skin substrate were: Poly(dimethylsiloxane) (PDMS) [31][32][33][34], other silicone rubber films [35,36], polyurethane (PU) [37][38][39], polyimide (PI) [40,41], polyethylene terephthalate (PET) [42,43], silk fabric-derived carbon textile [44], parylene [45][46][47], and even paper [48].…”

Printable anisotropic magnetoresistance sensors for highly compliant electronics

“…Printed magnetic field sensors have been underrepresented, mainly due to the complexity to obtain printable, well-conductive magnetosensitive composites with stable resistance readout [9,15]. The introduction of magnetic particles into elastomer matrices is one approach to obtain magnetoresponsive compounds [16][17][18][19][20]. Magnetic nanoparticles embedded in conductive agglomerates can be concatenated using an external magnetic field during the curing process of the binder (e.g.…”

Highly Sensitive 1T‐MoS2 Pressure Sensor with Wide Linearity Based on Hierarchical Microstructures of Leaf Vein as Spacer

“…[21] However, most sensors with 3D microporous conductive network can only tune the channel resistance, while shaping microstructures on rough surface only adjusts the contact resistance. [22][23][24][25] In addition, most microstructures are usually coated with uniform and small size conductive materials, which mainly modulate conduction under loading process, resulting in significant contact resistance and limited sensitivity. [26][27][28][29] Also, the microstructures are always fabricated by complicated, costly and time-consuming lithography processes.…”

“…The other decisive factor, the conductive active materials, should sensitively reflect corresponding current feedback on pressure loading. Different materials such as carbon nanotubes (CNTs), [22,23,30] graphene, [20,24,31] polymers, [21,32] and nanoparticles [33] have been widely explored. Polydimethylsiloxane (PDMS), as a widely used sponge with a large porous structure interacts poorly with small microstructures such as 1D nanowires or nanoparticles, influencing the stability of the pressure sensor.…”

“…The total resistance of sensor, which has a critical role to improve the sensitivity in wide range of linearity, largely relies on intricate structural design that mainly contains channel resistance of the active materials and the contact resistance between electrodes and the active materials . However, most sensors with 3D microporous conductive network can only tune the channel resistance, while shaping microstructures on rough surface only adjusts the contact resistance . In addition, most microstructures are usually coated with uniform and small size conductive materials, which mainly modulate conduction under loading process, resulting in significant contact resistance and limited sensitivity .…”