In Situ Dynamic Manipulation of Graphene Strain Sensor with Drastically Sensing Performance Enhancement

Abstract

It is extremely challenging to directly observe how the relative position of the nanosheet changes the charge transport in the channel. Previous work on graphene stacking strain sensors relies on nanosheet slip to detect small mechanical signals. However, the direct experimental verification evidence is still inadequate. In this work, the sliding conductive transmission of graphene nanosheets slip is directly measured through an improved in situ transmission electron microscopy observation technique. By accurately manipulating the atomic scale of graphene nanosheets to achieve nanoscale sliding, the resistance change between nanosheets in the in situ observation system can be directly measured. Besides, a mechanical sensor based on graphene layer structure is designed, which demonstrates a high gauge factor (4303 at maximum strain of 93.3%), negligible hysteresis (5–10%), and excellent stability over 3000 stretch–release cycles. Besides, the precise control of characteristics offers a practical approach of retaining high stability from device to device. This strain sensor is applied in various cases, especially the health monitor of the human cervical vertebra.

Approaching the Limit of Electromechanical Performance in Mixed-Phase Nanocomposites

“…Using the abovementioned fit parameters, in Figure , calculated values of dΔ R /d G for bulk isotropic and anisotropic nanocomposite systems using both 2D and 1D nanofillers were plotted as a function of the aspect ratio ( L / D ). First, it is noted that electromechanical response increases greatly with the aspect ratio and is reflective of previous reports, which showed similar increases when varying the aspect ratio of 2D and 1D − nanofillers in a range of nanocomposite systems. This finding implies that a decreased number of connections in a nanofiller network brought about by larger aspect ratios and thus a high degree of exfoliation equality are two of the dominating properties which can govern the nanocomposite electromechanical response.…”

Graphene Decorated Fiber for Wearable Strain Sensor with High Sensitivity at Tiny Strain

“…To date, many wearable strain sensors based on graphene have been studied owing to its outstanding electrical, mechanical, and thermal properties. [ 24–27 ] Wang et al. developed a strain sensor based on reduced graphene oxide (RGO)‐decorated PU electrospun mats, and GF = 11 at 10% strain and GF = 79 at 100% strain were obtained.…”

“…[23] To date, many wearable strain sensors based on graphene have been studied owing to its outstanding electrical, mechanical, and thermal properties. [24][25][26][27] Wang et al developed a strain sensor based on reduced graphene oxide (RGO)-decorated PU electrospun mats, and GF = 11 at 10% strain and GF = 79 at 100% strain were obtained. [28] Cheng et al presented a graphene-based fiber with a "compression spring" structure, which possessed a detection limit of 0.2% strain (GF = 10 within 1% strain) and broad workable range (100%).…”

Stress-deconcentrated ultrasensitive strain sensor with hydrogen-bonding-tuned fracture resilience for robust biomechanical monitoring

“…It is worth noting that resistor thermal noise, which is positively associated with resistance, also significantly influences the detection output [13,19]. Therefore, highly conductive materials such as metals, liquid metal, graphene, carbon nanotubes (CNTs), metallic nanoplates and nanowires (NWs) are often used to construct conductive materials [20][21][22].…”