Flexible temperature-pressure dual sensor based on 3D spiral thermoelectric Bi₂Te₃ films

Dual-parameter pressure-temperature sensors are widely employed in personal health monitoring and robots to detect external signals. Herein, we develop a flexible composite dual-parameter pressure-temperature sensor based on three-dimensional (3D) spiral thermoelectric Bi₂Te₃ films. The film has a (000l) texture and good flexibility, exhibiting a maximum Seebeck coefficient of -181 μV K^-1 and piezoresistance gauge factor of approximately -9.2. The device demonstrates a record-high temperature-sensing performance with a high sensing sensitivity (-426.4 μV K^-1) and rapid response time (~0.95 s), which are better than those observed in most previous studies. In addition, owing to the piezoresistive effect in the Bi₂Te₃ film, the 3D-spiral deviceexhibits significant pressure-response properties with a pressure-sensing sensitivity of 120 Pa^-1. This innovative approach achieves high-performance dual-parameter sensing using one kind of material with high flexibility, providing insight into the design and fabrication of many applications, such as e-skin.