Graphene enhanced flexible piezoelectric transducers for dynamic strain measurement: from material preparation to application

Abstract

In this study, graphene particles are introduced to the lead magnesium niobate-lead titanate (PMN-PT) and polyvinylidene fluoride (PVDF) to form a flexible ternary composite. The graphene concentration is rigorously designed and morphologically optimized, warranting good piezoelectric and dielectric properties. The piezoelectric and dielectric performances are greatly increased compared with the pure PVDF films. Then a theoretical model is formulated to quantitatively interpret the graphene effect on the permittivity performance and to provide guidelines for the optimization of graphene volume fraction. Moreover, a simple and cost-effective technique is designed to package the composite film as a large-area, lightweight and flexible transducer. Several confirmatory experiments and a proof-of-concept test are performed based on the proposed flexible piezoelectric transducers to validate the capability of the dynamic strain sensing. By comparing with the results from conventional strain gauges and ceramic piezoelectric wafers, it is verified that the proposed flexible transducer has proven responsivity and precision in responding to quasi-static strain, medium-frequency vibration, and ultrasound. The great potential of the developed transducer for a wide range of applications including structural health monitoring and human motion detection has been demonstrated.

2D Material‐Based Wearable Energy Harvesting Textiles: A Review

“…[104] Graphene-based 2D materials have been used as electrodes or in conjunction with piezoelectric materials to enhance the overall piezoelectric performance of wearable and textile-based PENGs. [105][106][107][108][109] Other 2D materials such as molybdenum diselenide (MoSe 2 ), WS 2 , MoS 2 , and MXene have been studied for their piezoelectric effects in wearable applications. [42,102,110] These investigations have emphasized the promise of 2D materials in wearable energy harvesting applications, notably directing toward the development of textile-based mechanical energy harvesting garments.…”

Highly Sensitive and Wide Detection Range Thermoplastic Polyurethane/Graphene Nanoplatelets Multifunctional Strain Sensor with a Porous and Crimped Network Structure

“…11,12 To achieve high sensitivity or a broad strain range, researchers have explored various elastic materials such as thermoplastic polyurethane, 13−15 hydrogels, 16 PDMS, 2 polyvinyl alcohol, 17 etc. They have employed methods to fabricate flexible strain sensors by combining these materials with conductive fillers, with choices ranging from conductive particles like carbon black, 18 one-dimensional metal nano-wires, 19 and carbon nanotubes 20 (CNTs) to two-dimensional materials such as graphene 21 and MXene, 22 either individually or in combination. 15,23 Zhou et al 24 reported a flexible strain sensor using coaxial wet spinning technology to enhance the strain range by encapsulating carbon nanotubes with thermoplastic polyurethane.…”

“…Flexible strain sensors are electronic devices widely used in human-wearable technology and human–machine interaction, playing a crucial role in engineering applications. − These sensors have garnered attention for their broad working range, high sensitivity, excellent durability, and stability, finding extensive applications in human motion detection, disease diagnosis, electronic skin, soft robotics, and more. − Traditional strain sensors are typically suitable only for smaller working ranges, struggling with large strains and complex deformation environments. , In contrast, flexible strain sensors, unrestricted by the rigidity and brittleness of metals, not only adapt to various strain conditions but also exhibit outstanding mechanical compliance and flexibility, making them suitable for complex, wide-ranging working environments. , To achieve high sensitivity or a broad strain range, researchers have explored various elastic materials such as thermoplastic polyurethane, − hydrogels, PDMS, polyvinyl alcohol, etc. They have employed methods to fabricate flexible strain sensors by combining these materials with conductive fillers, with choices ranging from conductive particles like carbon black, one-dimensional metal nanowires, and carbon nanotubes (CNTs) to two-dimensional materials such as graphene and MXene, either individually or in combination. , Zhou et al reported a flexible strain sensor using coaxial wet spinning technology to enhance the strain range by encapsulating carbon nanotubes with thermoplastic polyurethane. Although this sensor achieved a working strain range of 100%, its measured gauge factor (GF) was only 425.…”

Modeling and solving for vibration and buckling of circular functionally graded dielectric plates reinforced by graphene platelets considering complex conditions

“…With the increasing intelligence of electronic components, the studies on smart materials and their structures have attracted more and more attention of researchers [1,2]. Among them, the applications of graphene in smart composites are the most interesting research [3,4]. Graphene has excellent electrical, mechanical and thermal properties.…”