Piezo-resistive stress sensor based on MXene for energy harvesting

Current piezo-resistive stress sensors are more complex due to their structural designs, materials, fabrication techniques and multiple components such as electrodes, sensing layers and multiple substrates which directly affect the electrical measurements. This complexity of the piezo-resistive sensors led to inconsistent performance, lower sensitivity and higher rate of wear and tear. Due to these challenges, the self-powered energy from the piezo-resistive stress sensors could not be used effectively.The goal of this work is to develop and fabricate a novel piezo-resistive stress sensor based on MXene which could be used in energy harvesting to facilitate gait monitoring as an application of the Tribo-Electric Nano Generator. Utilizing the piezo-resistive effect, the sensors are designed to measure mechanical stress and strain by converting them into electrical signals. High electrical conductivity, mechanical flexibility, and enhanced piezo-resistive response are the excellent properties offered by the MXene material for different sensing applications. The work performs an extensive characterization after fabricating the sensors using a simple and scalable process to ensure its performance in terms of sensitivity, stability, and repeatability. The devices were fabricated to measure mechanical stress, sensitivity, and tribo-electric measurements by converting them into electrical signals which leads to energy harvesting by storing the energy in a capacitor. With high electrical conductivity, mechanical flexibility, and piezo-resistive characteristics, MXene based device offers novel sensing and tribo-electric related applications too. Using pure MXene layer as the core material, this work introduces a pioneering study focused on stress monitoring by piezo-resistive stress sensor and tribo-electric nanogenerator.