Wearable Self-Powered Biosensors Based on 2D Materials on Textile Platforms

Revolutionary advancements in healthcare and well-being rely on the integration of cutting-edge self-powered sensing technologies within textiles. A pivotal breakthrough in this field involves the emergence of nanoscale self-powered sensors specifically triboelectric nanogenerators (TENG). The underlying principle of TENGs lies in the combination of the triboelectric effect, based on the interaction between materials with different electronegativity and electrostatic induction. TENG devices have the capacity to effectively harness untapped energy resources, for example they can convert biomechanical energy from human movements such as walking, running, and breathing into electricity. TENG based biosensors are emerging as a viable alternative to battery-powered devices due to their self-powered and environmentally friendly properties. As a result, they are well-suited for wearable health monitoring applications, where they can behave as self-powered sensors. To pave the way for these transformative advancements, it is crucial to develop flexible, mechanically robust, lightweight, and resilient TENG biosensors.<br/>In this invited talk, I will present our recent work on the solutions we explored to the design and fabrication of such generators, which possess the vital characteristics to meet the demands of practical applications. I will present several approaches for the development of textile-based triboelectric nanogenerators using 2D materials both as active sensing layers and as electrode materials. In our earlier work we demonstrated various methods to integrate graphene with textile substrates and create electrodes displaying displayed a good range of conductivity, and resilience to bending, compression and tension.<br/>These textile electrodes are used in the fabrication of TENGs along with a triboelectric layer of polydimethylsiloxane (PDMS) polymer and nylon fabric as a counter triboelectric layer. Different parameters affecting the TENG output such as chemical modification of the PDMS layer, frequency, contact force, contact area and separation distance between the two triboelectric layers are studied to provide insights into the working mechanisms of the device and to enhance the TENG output. The flexible textile TENG presents a stable output performance under strong deformation and its sensitivity to movement was explored as wearable sensor to monitor biomechanical movements. Due to the conformation ability of the triboelectric sensors, they were able to be implemented on key moving parts of the human body and used to monitor biomechanical motion through electrical signals. The self-powered sensors demonstrate their potential for wearable bioelectronics, intelligent robotics, prostheses, and rehabilitation purposes. Furthermore, we have demonstrated the use of 2D Transition Metal Dichalcogenides materials for wearable sweat sensors of uric acid for applications in personalised healthcare. Among the emerging technologies for continuous monitoring wearable technologies, triboelectric nanogenerators have emerged as a particularly promising and innovative approach for self-powered sensors in the detection of sweat biomarkers.<br/>These results show that the distinctive combination of electrical, morphological, and mechano-elastic properties positions these 2D materials attractive candidate for the development of self-powered sensing textile technologies.