Flexible Pressure Sensor Decorated with MXene and Reduced Graphene Oxide Composites for Motion Detection, Information Transmission, and Pressure Sensing Performance

Abstract

Although fiber-based flexible piezoresistive pressure sensors have received extensive attention because of their simple fabrication and easy integration, the common practice of using a single material as the sensing layer often leads to unsatisfactory sensitivity and a limited sensing range. Herein, we exploit the combination of reduced graphene oxide (rGO) and two-dimensional transition-metal carbides and nitrides (MXene), use a polyester filament (PET) as the fiber matrix, and fabricate an MX/ rGO PET-based flexible pressure sensor using the "dipping-drying" method. A systematic study is conducted concerning the effect of the dip-coating sequence and material combination on the sensor's resistance and sensitivity, which reveals that MX/rGO PET has the smallest resistance and the highest sensitivity (1.24 kPa −1 ). A series of tests are conducted to evaluate the pressure sensing characteristics of the MX/rGO PET-based pressure sensor, confirming its good linearity, fast response speed, low detection limit, and stable performance. In addition, the sensor has been successfully used to monitor various human joint activities and physiological signals such as breathing, demonstrating great application potential in the field of personal health care. To further enhance the practical utility, an APP has been designed to analyze and display the collected signals, and the constructed sensor network also provides an ingenious method for information encryption and transmission via pressure sensing. In all, the MX/rGO PET-based pressure sensor proposed in this work is expected to provide a competitive scheme for wearable flexible electronic devices in information transmission and human−computer interaction in the future.

Ti3C2Tx MXene Paper-Based Wearable and Degradable Pressure Sensor for Human Motion Detection and Encrypted Information Transmission

“…This speech recognition capability will be of great value in assisting the rehabilitation of patients with damaged vocal cords. The respiratory state is an important indicator for assessing people’s health and analyzing motion. − In today’s epidemic environment, the monitoring of people’s breathing status when wearing masks is particularly important. As shown in the inset of Figure f, we placed the sensor on the surface of the medical mask, and respiration of different speeds can be distinguished by monitoring the change period of the current signal.…”

Coaxial Graphene/MXene Microfibers with Interfacial Buffer-Based Lightweight Distance Sensors Assisting Lossless Grasping of Fragile and Deformable Objects

“…Among the fresh generation of intelligent electrosensing materials, two-dimensional (2D) materials with a foam structure have attracted great attention in the field of intelligent sensing because of their low cost and light weight. − Graphene and MXene as the typical carbon-based 2D materials show great application prospects in piezoresistive sensors with flexibility and compressibility performance. − However, it is difficult for pure graphene foam to achieve high sensitivity and stability without additional additives or structural design due to poor conductivity and mechanical strength. , Although the pure MXene material itself has good electrical conductivity, it is difficult to process it into self-supporting foam because of its intrinsic weak gelation capability, which remarkably limits its wide application . Here, by combining the advantages of reduced graphene oxide (rGO) and MXene materials with the coaxial structure design, we constructed an ultra-fine and lightweight coaxial heterogeneous microfiber.…”

Tuning the Piezoresistive Behavior of Graphene-Polybenzoxazine Nanocomposites: Toward High-Performance Materials for Pressure Sensing Applications

“…To overcome the limitations of traditional pressure sensors based on metals and semiconductors, e.g., rigidity, high production costs, and cumbersome processability, research efforts are currently focused on the development of novel systems comprising flexible components and featuring superior mechanical properties and cost-effective and scalable production and processing. Various nanomaterial-based systems (including MoS 2 , MXene, and gold nanoparticles) are being explored as candidates for pressure-sensitive active materials that, once integrated into a device with appropriate flexible substrates and electrodes, can ensure high sensitivity, durability, and fulfillment of all the aforementioned characteristics. , Among them, graphene and its derivatives are particularly appealing since they display excellent electrical and mechanical properties, high flexibility, and lightweight, rendering graphene-based materials particularly suitable for application in pressure sensing . One common approach to integrating graphene-based materials in a pressure sensor consists in their incorporation into flexible or elastic substrates, such as rubbers, , fibers, , fabrics, , or polymer matrices. ,, With this approach, various types of pressure sensors featuring different structures have been integrated into capacitive, , piezorestistive, , and piezoelectric , sensors.…”