Single‐Crack‐Activated Ultrasensitive Impedance Strain Sensor

Abstract

A development of single-crack-activated impedance strain sensors with unprecedented sensitivity is demonstrated first. The gauge factor of the device is beyond 10 8 in 10 −4 strain range in comparison with the reported highest gauge factor 1.5 × 10 5 within 6e-1 strain range, and the displacement sensitivity is 1.6 MΩ nm −1 . The extremely high sensitivity is attributed to the transition region which has never been studied before. Multiplecrack-based sensors, however, cannot work in the transition region due to complicated interaction among cracks, which essentially limits their sensitivity. Additionally, studying a precisely controllable single crack rather than multiple cracks is favorable for excluding other factors such as crack spacing, difference among cracks, and interaction among cracks, simplifying the model and facilitating better understanding of the underlying mechanism of the device. The device can satisfy requirements of mechanical flexibility, durability, and repeatability. In addition, the device developed is capable of measuring displacement in nanometers range or force in tens of nanonewton range, and has the potential to be applied in various fields, such as specific biomolecular recognition.

Crack-based and Hair-like Sensors Inspired from Arthropods: A Review

“…The stain sensor made with multi-layer silver Schematic diagram of crack-based sensor based on PDMS. (a) One-step direct transfer preparation process of Ag Np-based tensile strain sensor on PDMS substrate [60] ; (b) molecular dynamics-based numerical simulation results of Ag-Np film stretching/relaxation process [60] ; (c) schematic diagram of the working principle of a single-crack-based strain sensor [1] ; (d) the template transfer method is used to fabricate the CBS [69] .…”

“…The increased sensitivity due to the increased crack density also leads to the complexity of the process of processing the signal, and the sensor exhibits unstable performance. Ye et al reported a single-crack-activated ultra-sensitive crack-based strain sensor [1] . Within the strain range of 10 −4 , the gauge factor of the device is beyond 108.…”

“…In recent years, researchers have been paying more and more attention to biological sensory system, especially the mechanical sensilla of arthropods. From imitating external forms to imitating internal mechanisms, people have developed mechanical sensors with high sensitivity [1] , low power consumption [2] and high compatibility [3] . However, we still have a lot of challenges in comprehensively understanding existing sensors.…”

“…Crack-based Sensor (CBS) mainly perceives strain parameters [1] . The base material is diverse, and the common materials can be classified into a variety of Journal of Bionic Engineering (2020) Vol.17 No.5 868 substrates, which can be commonly classified into poly-urethane acrylate (PUA), polydimethylsiloxane (PDMS), polyethylene terephthalate (PET), and paper.…”

Thin Ag films adhesive onto flexible substrates with excellent properties for multi‐application

“…carbon nanotubes, graphene), metal films, conductive polymers, and their hybrid micro/nanostructures. [8][9][10][11] Silver, including Ag nanowire, 12 nanoparticles, 13 inks, 14 and flakes, 15 has been the widest used metal materials in flexible electronics, due to its highest electronic conductivity of all metals, chemical stability higher than that of Cu, acceptable cost lower than that of Au. 16,17 For example, by mixing silver nanoparticles into rubber fibers, Park et al prepared a highly stretchable circuits through a fabrication process that can incorporate nozzle printing, inkjet printing, and spray printing to fabricate strain sensor.…”