Flexible and Sensitive Triboelectric Nanogenerator Strain Sensors Made of Semi-Embedded Aligned Silver Nanowires

Abstract

Recently, flexible strain sensors have attracted great attention due to their wide applications in human-machine interface interaction, healthcare, soft robotics, etc. While many reported flexible strain sensors are stretchable, the stability of sensors under long-term deformation is still a significant challenge. In this work, a strain sensor has been fabricated by encapsulating semi-embedded aligned silver nanowires with a PDMS layer, showing a maximum gauge factor of 396.3 at 100% strain and a durability of 3000 cycles stretching. The strain-sensitive material also remains stable after multiple bending and twisting during the 10000 cycles test. Furthermore, the strain sensor is endowed with a triboelectric nanogeneration function based on the triboelectric nanogeneration effect. The device has a maximum output power density of 9.36 mW m⁻², allowing it to realize strain sensing while converting the mechanical energy produced by daily activities into electrical power. As proof of demonstration, attaching the device to the finger joint provides accurate real-time strain sensing and stable output of triboelectric power.