Self‐Powered Flexible Sensor Based on the Graphene Modified P(VDF‐TrFE) Electrospun Fibers for Pressure Detection

Abstract

Polymer P(VDF‐TrFE) has been extensively applied in modern flexible electronics, such as nanogenerators and pressure sensors. In this study, a repolarization method is proposed to exploit the piezoelectric properties of the P(VDF‐TrFE) electrospinning film modified by the reduced graphene oxide (rGO). Then, the repolarized composite film is applied as the self‐powered flexible pressure sensor. Notably, the piezoelectric output voltage and current of the repolarized composite film are up to 1.5 V and 0.125 µA, respectively. Typically, the piezoelectric voltage of the composite film is three times as high as that of the pure spinning film. Meanwhile, this composite film also exhibits piezoresistive effect, which is ascribed to the 3D network structure of the electrospun nanofibers. In addition, the highest piezoresistive sensitivity of the pressure sensor is 0.072 kPa−1. To sum up, the pressure sensor fabricated in this study allows to simultaneously detect the static and dynamic pressure loads, which thereby has great application potentials in electronic skins (e‐skins) for human motion monitoring, such as motion state and finger bending.

Hydrophobic and Stable MXene–Polymer Pressure Sensors for Wearable Electronics

“…The applied external pressure increases the number of contact points between conductive MXene particles, generating more current pathways resulting in a significant increase in the contact area of the hybrid film. When the pressure is released, the compressed pressure sensor device returns to its original state and the contact area between multilayer MXene particles reduces owing to the flexibility of the sensing film. − The current response of the Ti 3 C 2 T x @P­(VDF-TrFE) sensor with a mass ratio of 1:1.6 with various applied pressures (Figure b) shows that the current gradually increases with increasing applied pressure, demonstrating that the fabricated sensor could distinguish different levels of pressure.…”

Piezoresistive design for electronic skin: from fundamental to emerging applications

“…Liu et al 117 fabricated a piezoresistive sensor that was composed of a dielectronic layer (Electronic polyvinyl alcohol (PVA) nanowires) sandwiched between ultrathin wrinkled graphene films, obtaining excellent piezoresistive sensitivity. Similarly, using electrospun PVA nanowires as a spacer between wrinkled conductive polypyrrole films, Luo et al 118 assembled a piezoresistive sensor with subtly controlled conductive paths. Beyond a simple sensing mechanism of conductive path change, the electrospun nanofibers as a spacer enabled the multiple changes of effective contact, leading to higher sensitivity and wider response range.…”

Graphene doping to enhance the mechanical energy conversion performances of GR/KNN/P(VDF-TrFE) flexible piezoelectric sensors

“…Among them, one of the widely used methods is to dope different kinds of functional fillers into the polymers to increase the b-phase content in the crystal region of P(VDF-TrFE). For example, perovskite ceramics, [11][12][13] carbon based materials (graphene, 14,15 graphene oxide, 16 carbon nanofibers, carbon nanotubes, 17 etc. ), metal oxides, 18,19 metal particles 20 and other functional fillers (polyhedral oligomeric silsesquioxane (POSS)), 21 and boron nitride nanotubes (BNNTs) 22 are usually used to regulate the interfacial effect and crystal structure of P(VDF-TrFE).…”