Spongy Single-Electrode Triboelectric Nanogenerator Performance Improvement And Pressure Sensing Application

Flexible pressure sensors are widely used in emerging fields such as the Internet of Things(Io T)and Artificial Intelligence(AI)due to their excellent force-electric coupling characteristics,especially in human motion monitoring and medical health,which have broad application prospects.However,there are still some problems in the development of flexible pressure sensors,such as poor sensing performance,complex structure,single application scenarios,and difficult energy supply.The flexible pressure sensor based on nanogenerators has attracted much attention because of its characteristics of self-energy and flexibility.However,due to the problems of low sensitivity,narrow measuring range,long response time,and poor stability of the traditional pressure sensor,its practicability is poor and can not meet the current demand.Therefore,a spongy single-electrode triboelectric flexible pressure sensor composed of a composite multi-walled carbon nanotube/polydimethylsiloxane(MWCNT/PDMS)film and a conductive fabric is proposed in this paper.In the single-electrode contact-separation mode,the sensor operates based on the coupling of the triboelectric initiation effect and electrostatic effect.The device is a combination of dielectric modulating material and spongy porous structure,with excellent output performance,high sensitivity,wide measurement range,and so on,which becomes an effective way to solve the above problems.When the content of MWCNT in the composite film is 10 wt%,the best output of peak open circuit voltage(Voc)is 2.82 times that of the flat PDMS film;when the porosity of the composite film reaches 64%,the corresponding best Voc is 1.85 times that of the flat composite film;the sensor has a wide measurement range(1.5 k Pa ～ 316.5 k Pa),high sensitivity(two sensitivity regions(slope): 1.324 V/k Pa for 1.5 ～28 k Pa;0.096 V/k Pa for 28 ～ 316.5 k Pa,and their linearity is 0.986 and 0.979,respectively),the short response time(23ms),and over 7000 cycle tests,with good stability and reliability.In addition,the pressure sensor can be used to monitor different active layer materials,hand pressure changes,human movement posture,spatial personalized recognition,and other scenarios.In this paper,a sponge-like single electrode triboelectric flexible pressure sensor is proposed,which not only optimizes the performance with high electrical output,high sensitivity,and wide measurement range;but also solves the problems of fewer application scenarios and complex structure;at the same time,it also overcomes the difficulties of traditional rigid power supply which can’t sustain power supply,environmental pollution,and poor flexibility.It provides a new idea for the research of flexible pressure sensor design systems,which show great development potential in the fields of healthcare,sports rehabilitation,and humancomputer interaction.