Stretchable and highly sensitive graphene-on-polymer strain sensors

Abstract

The use of nanomaterials for strain sensors has attracted attention due to their unique electromechanical properties. However, nanomaterials have yet to overcome many technological obstacles and thus are not yet the preferred material for strain sensors. In this work, we investigated graphene woven fabrics (GWFs) for strain sensing. Different than graphene films, GWFs undergo significant changes in their polycrystalline structures along with high-density crack formation and propagation mechanically deformed. The electrical resistance of GWFs increases exponentially with tensile strain with gauge factors of ~103 under 2~6% strains and ~106 under higher strains that are the highest thus far reported, due to its woven mesh configuration and fracture behavior, making it an ideal structure for sensing tensile deformation by changes in strain. The main mechanism is investigated, resulting in a theoretical model that predicts very well the observed behavior.

Extremely Stretchable Strain Sensors Based on Conductive Self‐Healing Dynamic Cross‐Links Hydrogels for Human‐Motion Detection

“…The gauge factor is higher than that of the hydrogel without electronic conductor (from 0.09 at 100% strain to 0.53 at 1000% strain), and other piezoresistive electronic strain sensor (0.06 at 200% strain)8 and capacitive soft strain sensors based on ionic conductor (0.348 ± 0.11 at 700% strain) 20. Although some strain sensors exhibit much higher gauge factors, the poor stretchability and lack of self‐healing capability restrict their applications under rigorous mechanical deformations 47, 48, 49…”

High Strength Metallurgical Graphene – Mechanisms of Growth and Properties / Grafen Metalurgiczny O Wysokiej Wytrzymałości – Mechanizmy Wzrostu I Właściwości

“…Moreover, the tensile test confirmed the substantially higher mechanical strength of sc-HSMG (more than three times higher strain at the conductivity loss) compared with CVD and c-HSMG. Therefore, sc-HSMG sheets seem to be a good candidate for further investigations as a functional nanomaterial for future efficient hydrogen storage systems [21], reinforcing sheets in composites [22], strain sensors [4], filtering membranes [23] and many others. Type of the band structure conductor conductor semi-conductor…”

“…5). The star-like graphene nuclei A slight overlapping of neighboring graphene flakes occurs, providing continuity in the graphene sheet [4]. That is why the CVD graphene grains boundaries are likely bilayered and held together by π-bonds.…”

“…The most common CVD graphene is a polycrystalline 2-dimensional material composed of partially overlapped, randomly oriented flakes [4]. This type of structure results from the spontaneous and random nucleation of graphene flakes onto a solid body that is not perfectly flat [14].…”

“…For graphene electronic applications, it is important to establish a relationship between the electrical properties and the material stress state. By altering the stress, the mobility of the electric charge can be changed, which is particularly important for applications in electronic circuits such as field-effect transistors, transparent electrodes on flexible substrates and strain gauges [3,4]. Most of the studies on the impact of the graphene deformation on its properties are model-based research using molecular dynamics [5][6][7].…”