Temperature Decoupling of a Hydrogel-Based Strain Sensor under a Dynamic Temperature Field

Hydrogels possess several interesting characteristics and have attracted increasing attention for flexible interactive strain-sensing. However, hydrogel strain sensors are easily influenced by temperature because of the intrinsic characteristics of the materials, thus, their sensing accuracy is significantly affected. Herein, a strategy is proposed to eliminate the influence of temperature by building an in-situ hydrogel temperature sensor next to the strain sensor to monitor ambient temperature changes and simultaneously correct the strain signal. By introducing silicon nanoparticles and modified graphene, the hydrogel exhibits a good balance between conductivity and stretchability. The hydrogel strain sensor exhibits a working range of up to 1000% and a sensitivity of 8.1. It can monitor human movement and shows good stability. Moreover, the hydrogel-based sensor demonstrates an impressive thermal response sensitivity (-7.16% degrees C-1). This bimodal sensor not only realizes the decoupling of the strain sensor from the temperature but protects the temperature sensor from the influence of strain. More importantly, the device is also able to accurately control the manipulator under dynamic temperatures, proving the feasibility of the design. This strategy provides a new method to eliminate the influence of temperature on strain sensing and assists in the development of the interactive-sensing field.