Natural Material-based Triboelectric Nanogenerator For Wearable Devices

With the rapid development of flexible electronic technology,intelligent wearable electronic devices are gradually changing people’s life.As the core component of these devices,the power source requires not only continuous energy supply but also wearable characteristics and durability,which many traditional power sources fail to achieve.Triboelectric nanogenerator（TENG）can collect random mechanical energy in the environment and convert it into electrical energy,which can be used as micro/nano energy and self-powered sensors.Flexible TENGs constructed from natural materials have great advantages in the field of wearable electronics,due to the inherent biocompatibility of natural materials that can alleviate the discomfort caused by wearing wearable electronic devices for a long time,and the degradability of natural materials that can effectively reduce electronic waste.Therefore,in this paper,based on natural casings andβ-chitin which are biodegradable and biocompatible,natural casings film-based flexible TENG andβ-chitin based TENG are designed and constructed,and their potential applications in intelligent wearable devices are explored.The main contents are as follows:（1）Based on the characteristics of ultra-light and ultra-flexible natural casing film,a natural casing film-based single electrode TENG（NCF-TENG）is designed and constructed,and its application as electronic skin in human-machine interaction is explored.The NCF-TENG exhibits good electrical output performance and fatigue resistance.At a frequency of 2.5 Hz,the open circuit voltage of the NCF-TENG reaches196 V,short circuit current is 5.1μA,and transfer charge is 72 n C,and its can stably cycle at least 1000 cycles.In addition,the electrical signals output from NCF-TENG are converted into digital signals by a programmed microcontroller to design a casing film-based friction electronic skin,which successfully realizes the human-machine interaction functions such as password unlocking,input searching,and game playing.NCF-TENG is expected to further improve the bionic level of electronic skin and provide new solutions for wearable electronic devices and human-machine interaction.（2）β-chitin is extracted from waste cuttlefish cartilage,andβ-chitin fiber membrane is prepared by electrospinning technology to construct naturalβ-chitin-base TENG（BCHT-TENG）and explored its application in intelligent sports.BCHT-TENG has excellent electrical output performance,with open circuit voltage of 203 V,short circuit current of22μA,and corresponding current density of 9.6 m A·m^-2.The best matching resistance of BCHT-TENG is 3 MΩ,and the maximum instantaneous output power density is 777m W·m^-2.In addition,the BCHT-TENG array is constructed and worn on the athlete’s sneakers.According to the current signals output by BCHT-TENG at different positions,the player’s contact position and the player’s running state can be monitored,providing a real-time monitoring for football coaches.BCHT-TENG provides new solutions for intelligent device interconnection,intelligent sports monitoring and other fields.