TeNWs/Ti₃C₂T_x Nanohybrid-Based Flexible Pressure Sensors for Personal Safety Applications Using Morse Code

This report demonstrates the fabrication and development of a tellurium nanowire (TeNW) and MXene (Ti3C2Tx) nanohybrid-based pressure sensor. The fabricated sensor was later encapsulated in poly(dimethylsiloxane) (PDMS) and used as buttons for the communication system to demonstrate a personal safety application using Morse code. The fabricated pressure sensor demonstrated an excellent sensitivity of 9.29241 kPa–1 and stability withstanding over ∼3000 cycles of applied pressure (∼1.729 kPa). Real-time ultraviolet photoelectron spectroscopy (UPS) is utilized for realizing the band diagram of the TeNWs/Ti3C2Tx nanohybrid to understand the transport of charge carriers upon external pressure. The transduction mechanism of the fabricated pressure sensor is explained using the improved intrinsic piezoresistive properties of the MXene and TeNWs in TeNWs/Ti3C2Tx, which helps in increasing the tunneling current by a decrease in the effective interlayer resistance/interwire tunneling distance of the nanohybrid. Further, an Android application was created to wirelessly receive data via Bluetooth from the sensors connected to a microcontroller. The application displayed the pattern pressed on the sensors as a Morse dash or dot. This can further be used in a similar fashion to that of a telegraph to send complex messages such as “HELP”. Developing a TeNWS/Ti3C2Tx nanohybrid-based flexible sensor opens many possible wireless monitoring and communication applications.