Bioinspired Spinosum Capacitive Pressure Sensor Based on CNT/PDMS Nanocomposites for Broad Range and High Sensitivity

Abstract

Flexible pressure sensors have garnered much attention recently owing to their prospective applications in fields such as structural health monitoring. Capacitive pressure sensors have been extensively researched due to their exceptional features, such as a simple structure, strong repeatability, minimal loss and temperature independence. Inspired by the skin epidermis, we report a high-sensitivity flexible capacitive pressure sensor with a broad detection range comprising a bioinspired spinosum dielectric layer. Using an abrasive paper template, the bioinspired spinosum was fabricated using carbon nanotube/polydimethylsiloxane (CNT/PDMS) composites. It was observed that nanocomposites comprising 1 wt% CNTs had excellent sensing properties. These capacitive pressure sensors allowed them to function at a wider pressure range (~500 kPa) while maintaining sensitivity (0.25 kPa−1) in the range of 0–50 kPa, a quick response time of approximately 20 ms and a high stability even after 10,000 loading–unloading cycles. Finally, a capacitive pressure sensor array was created to detect the deformation of tires, which provides a fresh approach to achieving intelligent tires.

Pressure Sensor Based on a Lumpily Pyramidal Vertical Graphene Film with a Broad Sensing Range and High Sensitivity

“…The results show that LPV-5 presents stable responses with excellent repeatability. Figure d shows a high sensitivity response over a wide response range compared to reported pressure sensors, demonstrating the supereminent sensing properties of our LPV-5 sensor. − …”

Rapid-Response and Highly Sensitive Piezocapacitive Pressure Sensor Based on Micro Buckling Periodic Layers for Wearable Applications

“…The high sensitivity along with the fast response may benefit from the face-to-face placement of the two different micro buckling structures. The sensitivity and response are superior to those of the newly reported vertical graphene/micropyramidal PDMS piezocapacitive pressure sensor, the reported capacitive sensor using a porous micropillar PDMS as the dielectric layer (∼20 ms), and the spinosum capacitive pressure sensor based on CNT/PDMS nanocomposites (∼20 ms) . The high sensitivity can be attributed to the micro pyramid structure of the dielectric layer and the air gap between the wrinkle structure and the pyramid structure.…”

“…The sensitivity and response are superior to those of the newly reported vertical graphene/micropyramidal PDMS piezocapacitive pressure sensor, 34 the reported capacitive sensor using a porous micropillar PDMS as the dielectric layer (∼20 ms), 44 and the spinosum capacitive pressure sensor based on CNT/ PDMS nanocomposites (∼20 ms). 45 The high sensitivity can be attributed to the micro pyramid structure of the dielectric layer and the air gap between the wrinkle structure and the pyramid structure. The micro pyramid produced using the buckling method may be more compressible than the similar patterns generated by other methods.…”

Capacitive Sensors with Hybrid Dielectric Structures and High Sensitivity over a Wide Pressure Range for Monitoring Biosignals

“…To achieve a high sensitivity over a wide range, Δε/ε r0 is another key parameter. Notably, studies have shown that adding a conducting filler to the polymer can result in large dielectric permittivity. − Here, MWCNTs are added to the high- E component of the GD to form the GHD. Figure e shows the Δ C / C 0 of the sensors based on the bulk dielectric (BD), GD, and GHD under different applied pressures.…”