The Flexible Magnetic Electronic Functional Materials and Devices Group led by Prof. LI Run-Wei at the Ningbo Institute of Materials Technology and Engineering (NIMTE) of Chinese Academy of Sciences (CAS) developed a strain-temperature dual-mode sensor with high stimuli discriminability and resolution, enabling real-time sensing of strain and temperature stimuli without cross-talk by a single sensor. This work was published in Advanced Functional Materials.
As important physiological parameters generated from human activities, strain and temperature play crucial roles in health and motion monitoring.
Flexible sensor is the core component of smart wearable devices, which follows the development trend of integration and multi-function in recent years. However, detecting and discriminating strain and temperature stimuli still remain challenging for a single sensor.
Co-based amorphous wire has excellent soft magnetic properties and giant magnetic impedance effect (GMI), which can realize highly sensitive detection of magnetic fields, thus has been recognized as an ideal material for the development of flexible multifunctional sensors.
Based on the Co-based amorphous wire as a sensitive material, scientists at NIMTE designed a dual-mode sensor with a tubular heterogeneous structure, realizing the monitoring and real-time discrimination of strain and temperature.
The developed sensor consists of a thermocouple coiled wound around a strain-to-magnetic induction conversion unit, and a Co-based amorphous wire with high permeability. By tailoring the mechanical modulus of the components of the strain-to-magnetic induction conversion unit, the strain sensitivity of the sensor can be adjusted.
The dual-mode sensor showed high strain sensitivity (gauge factor of 5.29), high temperature sensitivity (54.49 μV °C-1) and good cycling stability. In addition, this dual-mode elastic sensor realized low strain detection limit of 0.05% with the resolution of 0.1%, and the temperature sensing accuracy of 0.1 °C.
Furthermore, the dual-mode sensor was integrated in smart textile to monitor breathing, body movement and temperature continuously and independently, showing bright and broad application prospects in early disease diagnosis, health monitoring, and human-machine interaction.
This work was supported by the National Natural Science Foundation of China (Nos. 51971233, 52127803, U20A6001), the External Cooperation Program of Chinese Academy of Sciences (Nos. 174433KYSB20190038, 174433KYSB20200013), etc.
Fig. The strain-temperature dual-mode sensor with high stimuli resolution and discrimination (Image by NIMTE)
Contact
XIAO Huiyun
Ningbo Institute of Materials Technology and Engineering
E-mail: xiaohuiyun@nimte.ac.cn