Research On Flexible Triboelectric Nanogenerator And Its Application In Human Motion Detection

With the rapid development of Internet of Things technology and wearable electronic devices,the traditional battery energy power supply has been exposed to many shortcomings,such as limited lifetime and environmental pollution caused by discarded batteries.Also,the requirements for portability,wearability,and flexibility of energy are getting higher and higher.Recently,triboelectric nanogenerators,which have the advantages of high output power,simple preparation,low cost,etc.,have become a hot spot in related fields in recent years.Polydimethylsiloxane(PDMS)is selected as the frame material due to its good stretchability and flexibility and suitable for human wear.This paper studies the use of PDMS to construct and prepare the wearable and flexible triboelectric nanogenerator,and its applications in human motion detection.The specific research contents are as follows:(1)Tubular flexible triboelectric nanogenerator.The triboelectric material selection,fabrication process,and working principle of the freestanding mode flexible triboelectric nanogenerator were studied.The tubular wearable and flexible triboelectric nanogenerator were fabricated and its performance was analyzed and optimized.The effects of factors such as the number of freestanding layers,and the swing frequency,and the swing angle on the output performance of the device are studied.The experimental results show that increasing the number of freestanding layers is beneficial to improve the output performance,and higher frequency and angle are beneficial to increase the short-circuit current.After superhydrophobic surface treatment of FEP films,the experiment found that the output voltage of the tubular flexible triboelectric nanogenerator based on pure water was increased by 100%.The device has been tested for 3500 cycles,and its output performance has remained almost unchanged,proving that the generator has good stability and durability.The experimental results show that the tubular flexible triboelectric nanogenerator can be applied to the detection of different human motion states.(2)Flexible triboelectric nanogenerator based on liquid metal.The surface microstructure,preparation process,and working principle of the single-electrode flexible friction nanogenerator were studied,and a flexible triboelectric nanogenerator using liquid metal as the electrode and PDMS as the triboelectric layer was prepared.Using micro-nano processing technology,a PDMS with a square array microstructure on the surface is prepared,which improves the sensitivity of the generator,increases the contact area,and improves the output performance of the device.Using a linear stage to apply external forces of different frequencies to it,the output voltage is stable at 30 V,and the output current is increased from 0.5 μA to 1 μA.Subsequently,the change of open-circuit voltage and short circuit current of the generator under different pressures was tested,proving that it can detect different pressures.At the same time,the triboelectric nanogenerator can also be used for human daily movement energy collection and gesture detection.