Ta4C3 Nanosheet/Melamine Sponges with High Sensitivity and Long-Term Stability for Wearable Piezoresistive Sensors

Flexible and long-term stable piezoresistive sensors still have room for improvement, in terms of sensitivity and cost reduction. Therefore, future research will focus on developing pressure-sensitive materials with improved performance and reduced cost. This study presents a stable suspension of Ta4C3 nanosheet using an etching and intercalation method. Subsequently, a Ta4C3 nanosheet/melamine sponge was created through a dipping-drying method and utilized as a flexible framework for wearable piezoresistive sensors. The sensors demonstrate exceptional pressure-sensing performance, including a high sensitivity (4.01 kPa–1) over a wide linear range of 0.018–12.06 kPa, a low hysteresis, a low detection limit (18.5 Pa), a short response time (35.4 ms), and a quick recovery time (27.88 ms), as well as long-term stability and durability. These sensors can be utilized for real-time monitoring of various physiological activities in the human body. Moreover, they hold potential applications in wirelessly detecting human movement and robot motion.