Triboelectric Nanogenerator With High Energy Conversion Efficiency Driven By Wind

Wind energy is becoming increasingly important as a renewable energy source,accounting for a growing proportion of global power generation.By 2022,wind power is expected to make up 5.8%of global electricity generation.While wind turbine generators based on electromagnetic effects are currently the mainstream method of harvesting wind energy,their high cost,complex structure,and limited range of wind speeds make them unsuitable for use in urban areas.With the development of new-generation information technology,such as the Internet of Things,electronic devices such as sensors are becoming more mobile,intelligent,and wearable.To meet the energy needs of these distributed sensors,new wind energy collection technologies and portable wind energy collection devices are needed.The Triboelectric Nanogenerator（TENG）is a new type of mechanical energy harvesting device that offers unique advantages in collecting wind energy compared to traditional electromagnetic wind turbines.The Triboelectric Nanogenerator（TENG）is capable of collecting various forms of mechanical energy such as vibration,swing,and rotation,providing a diverse range of options for harvesting wind energy.Additionally,TENG is small in size,easy to fabricate,low in cost,and has a wide range of material sources.Compared to electromagnetic generators,TENG has a higher energy conversion efficiency when harvesting low-frequency mechanical energy（less than 5 Hz）,allowing for a wider range of wind speeds to be collected.Therefore,TENG has a promising future in wind energy harvesting.The output performance（open-circuit voltage,short-circuit current,and amount of transferred charge）and the conversion efficiency of mechanical energy are the key indicators for evaluating TENG.In this paper,firstly,the friction layer material selection improves the output performance of the wind-driven TENG.Secondly,the working state of TENG can be changed to improve the energy conversion efficiency of wind-driven TENG.In the second chapter of the study,a Fur-brush TENG（FB-TENG）was proposed,which uses soft and dense animal hair as the friction layer.The aim was to increase the contact area between the two friction layers,maintain close contact,and reduce the friction loss between the electrode layer and the electrode layer.The study found that the output performance of FB-TENG was the best when rabbit hair was used as the friction layer,with transferred charge and charge density reaching 2.0μC and 89μC m^-2,respectively.The material of the friction layer was optimized by considering the length,density,type,and rotation direction of the TENG.The study also explored the influence of friction interlayer pressure on the output of FB-TENG.The results showed that the fuller the contact between the friction layers,the better the output performance,but the greater the friction loss.Finally,FB-TENG was applied to the plasma CO₂ reduction system,and the excellent output performance and applicability of FB-TENG were proved through the CO yield and conversion efficiency.In chapter three,the aim was to improve the efficiency of TENG in collecting wind energy.To achieve this,a horizontal axis wind turbine with a higher wind energy utilization rate was selected and the number of blades was optimized.In addition,a double-layer TENG based on electrostatic adsorption and centrifugal force was proposed.The friction layer rubs against the inner electrode layer under the action of its own gravity when the wind speed is low.However,when the wind speed is high,the friction layer rubs against the outer electrode layer under the action of centrifugal force.The double-layer structure TENG avoids the loss caused by the friction layer’s own gravity,centrifugal force,and electrostatic force,thereby improving the efficiency of wind energy collection and prolonging the working life.The bilayer TENG can achieve a mechanical-to-electrical energy conversion efficiency of 10.3%when only relying on the electrostatic adsorption force.Moreover,after 7 million cycles,the transferred charge of TENG decreased by less than5.0%,and the loss of the friction layer was only 5.6%.Therefore,the bilayer TENG provides a wind energy harvesting technology with low friction loss and high energy conversion efficiency.As such,it holds significant promise for application in wind energy harvesting,self-driven sensing,and related systems.In this paper,aiming at improving the output performance and energy conversion efficiency of the TENG,the charge density of FB-TENG is proposed to reach 89μC m^-2,which improves the output performance of the TENG.The proposed double-layer TENG based on electrostatic adsorption and centrifugal force can minimize the friction loss caused by external force and improve the energy conversion efficiency from wind energy to electric energy,which has important theoretical significance for the application and promotion of wind-driven TENG.