Research Of The Design And Application Of The Triboelectric Nanogenerator And The Self-Powered Pressure Sensor

In the past decades,information technology has been the main driving force in the development of the world.The sensor is the most basic component and can sense changes in physical quantities of the external environment,such as temperature,sound,vibration,and pressure.However,sensors basically require an external power supply to provide energy,which not only reduces the life of sensor but also causes the pollution of environment.In recent years,people are trying to develop self-powered sensing system by solar energy,thermal energy,wind energy,and mechanical energy,achieving the device sensing and power generation in the same process.In human daily life,vibrational mechanical energy is common in nature,such as human walking,tire rolling and finger tapping.The energy is huge and varied.At present,there are several kinds of mechanical energy-electricity conversion principles including piezoelectric nanogenerator,triboelectric nanogenerator and etc.Among them,triboelectric nanogenerator has the advantages of simple structure,low cost,and light weight,and is very suitable for self-powered sensors.The principle of TENG includes frictional electrification and electrostatic induction using two materials with different triboelectric sequences to contact each other and then separate to generate triboelectric charges and electrostatic induced charges,thereby generating a potential difference between the two materials to drive the flow of electrons in the external circuit.In this paper,design and study have been done to solve the problem of self-power supply for pressure sensors.Firstly,this paper discusses the principle of triboelectric nanogenerator,simulates and then analyzes the electric potential distribution of the triboelectric generators through the COMSOL software.According to the results,we adopt the “arch structure” conducting TENG in order to make a larger gap between the friction materials.Hence,its output electrical signal is increased.Afterwards,process is designed for TENG.The friction materials are the silicone elastomer(PDMS)and polyethylene terephthalate(PET),whose friction sequence is great different.In order to increase the contact area between the friction materials,microstructures are prepared on the PDMS surface by a silicon template transfer method.Secondly,the functional test and analysis of the self-powered pressure sensor prove that the pressure sensor can convert the mechanical energy of finger tapping into electrical energy.Comparing and analyzing the output performances of the difference of microstructures(long groove and cubic microstructures),different microstructure sizes,different applied pressure,and different load.The results show that the output voltage of a self-powered pressure sensor with a cubic microstructure is 7 times higher than that without microstructure.The output voltage of cubic microstructure is 2 times higher than the long groove microstructure.The internal resistance of the sensor is 1.2 M? by measuring the output power at the load.The output power is micro-watt range.The self-powered pressure sensor designed in this paper can be used to monitor the movement of body.The results show that the self-powered pressure sensor based on TENG has potential application in wearable devices.Thirdly,the material properties of black phosphene and graphene oxide have been studied in this paper.The black phosphene and graphene oxide dispersions are fabricated on the surface of the copper film and then conducted a rubbing structure with the PDMS film.The output signals of them are smaller than the frictional contact between PDMS and PET.The test results show that the charge capacity of black phosphene and graphene oxide is smaller than that of PET,however the response time is faster.This has some guiding significance for the research and practice of TENG in the future.