Ti3C2Tx Mxene in transparent thin film heaters and iontronic pressure sensors

Çetin, Öykü
The remarkable properties of two-dimensional carbides, nitrides, or carbonitrides (MXenes) have resulted in their integration into a range of nanomaterial-based electronic applications. Researchers have explored MXenes’ potential in diverse areas, such as energy storage, sensing, and catalysis, highlighting their versatility and promising properties. Despite MXenes' extensive research history in electronic applications, its protective properties and utilization in iontronic pressure sensors have not been sufficiently explored. This thesis investigated the protective behavior of Ti3C2Tx MXene for copper nanowires (Cu NWs) and assessed its performance as electrodes of iontronic pressure sensors. The successful deposition of Ti3C2Tx MXene into Cu NW networks showcases substantial improvements in the stability and performance of bare Cu NW networks. The results demonstrated that Ti3C2Tx MXene deposition enhanced the stability of Cu NW networks to 10 months under ambient conditions, contrasting with the rapid increase in electrical resistance observed in bare Cu NWs network within ten days. Additionally, the fabricated transparent conducting electrodes (TCEs) exhibited long-term stability when used as transparent thin film heaters (TTFHs), maintaining consistent performance over a week. As a result of the improved stability without conceding transparency, fabricated Mxene/Cu NWs network-based TTFHs were utilized as wearable human thermotherapy patches and defrosting electrodes. Iontronic pressure sensors hold significant potential to emerge as vital components within the realm of flexible and wearable electronics, catering to various applications spanning wearable technology, health monitoring systems, and human-machine interaction systems. This thesis introduces an iontronic pressure sensor structure based on a seamlessly deposited Ti3C2Tx MXene layer on highly porous melamine foam as parallel plate electrodes and an ionically conductive electrolyte of 1-Ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide/thermoplastic polyurethane ([EMIM][TFSI]/TPU), coupled with carbon cloth for current collecting layers for improved sensitivity and high mechanical stability of more than 7000 cycles. MXene-deposited melamine foam-based iontronic pressure sensors (MIPS) showed a high sensitivity of 5.067 kPa-1 and a fast response/recovery time of 28/18 ms at a pressure of 4 kPa. The high sensitivity, high mechanical stability, and fast response/recovery time of the designed sensor make it a promising candidate for real-time body motion monitoring. Moreover, sensors were employed as a smart numpad for integration into advanced ATM security systems with the help of machine learning algorithms. This research marks a significant advance in iontronic pressure sensor technology, offering promising avenues for application in wearable electronics and security systems.
Citation Formats
Ö. Çetin, “Ti3C2Tx Mxene in transparent thin film heaters and iontronic pressure sensors,” M.S. - Master of Science, Middle East Technical University, 2024.