Simultaneous strain, strain rate and temperature sensing based on a single active layer of Te nanowires

Stress/strain-temperature sensors are capable of sensing both stress/strain and temperature stimuli, and are widely used in biological health monitoring and human-machine interaction. Conventional stress/strain-temperature sensors are prepared by stacking two single sensors, which have complex structures and often require external power to drive, making long-term stable monitoring challenging. Herein, we demonstrate a flexible single-channel multimodal sensor based on the combined thermoelectric and piezoelectric effects of tellurium nanowires. Based on the tilt-grown reticulated nanowire structure, the sensor can simultaneously sense strain/strain rate and temperature in a single channel of a single active layer of nanowire. The sensor exhibits a record-high strain/strain rate sensing performance with a strain sensing sensitivity of 0.454 V and a strain rate sensing sensitivity of 0.0154 V s, surpassing previous study benchmarks. Additionally, it showcases significant temperature-sensing performance with a sensitivity of 225.1 μV K^-1. The origin of the piezoelectric effect of the sensor is attributed, by experimental and computational evidence, to the change in atomic charge when the Te nanowires are bent, and it can be modulated by external electric fields, such as a thermoelectric potential. Our results provide insights for designing and fabricating high-performance flexible single-channel multimodal sensors.