Chemical conditioning was used to modify the triboelectrification of coal and mineral particles.The chemicals tested included starch,lignin,kerosene,ethanol,acetic acid,salicylic acid,sodium oleate,Sodium Hexametaphos...Chemical conditioning was used to modify the triboelectrification of coal and mineral particles.The chemicals tested included starch,lignin,kerosene,ethanol,acetic acid,salicylic acid,sodium oleate,Sodium Hexametaphosphate(SH),sodium silicate, Sodium Dodecylbenzenesulfonate(SDBS),Sodium Bicarbonate(SB) and ammonia.A high-speed,dry mixing method was employed.The charge-to-mass ratio of the coal and mineral samples,both untreated and treated,was tested using a Faraday cup. Dielectric constants were determined by measuring capacitance.It is found that the selectivity of the additives toward coal or minerals is not consistent.Salicylic acid is the optimal additive to enhance the triboelectrification performance of coal samples.Starch, lignin and sodium oleate are suitable for removal of pyrite.SH,sodium silicate,SDBS,SB and ammonia are suitable additives for the removal of ash-forming minerals.展开更多
The triboelectric effect,known since ancient Greece,is the accumulation of electric charges due to electron transfer when materials contact and separate.With technological advancements,the triboelectric effect has bee...The triboelectric effect,known since ancient Greece,is the accumulation of electric charges due to electron transfer when materials contact and separate.With technological advancements,the triboelectric effect has been applied in energy harvesting equipment,sensors,and smart devices,including triboelectric nanogenerators(TENGs).This effect shows potential for sustainable energy and next-generation intelligent systems.Triboelectric systems,as a type of tribological system,require state monitoring,behavior prediction,and system optimization.Tribo-informatics is an interdisciplinary field that combines tribology and informatics.By clarifying information representations and flows within tribological systems,tribo-informatics addresses the connections between physical tribological systems and embedded information systems.With a focus on the triboelectric effect,this paper proposes a method for information representation in triboelectric systems from a tribo-informatics perspective and suggests a research approach based on tribo-informatics to achieve research goals.The aim is to enable researchers to collect,process,and analyze tribological information more effectively to achieve specific research objectives.展开更多
Although triboelectrification(TE)is essential in many industrial and scientific fields,its charge transfer mechanisms are still not fully understood.In this paper,the charging-induced electric potential on the frictio...Although triboelectrification(TE)is essential in many industrial and scientific fields,its charge transfer mechanisms are still not fully understood.In this paper,the charging-induced electric potential on the friction surface and the discharging-induced light emission from the contact region during sliding frictions between insulators have been observed simultaneously.The results show that,in the absence of discharging,the temporal variations of surface potential at all the contact points are almost the same,experiencing a rapid growth in the initial stage,followed by a slow growth,and eventually reaching a stable value.To explain such a dynamics of electron transfer,a theoretical expression for the temporal evolution of the surface potential during TE process is proposed by considering the electron transfer as the charging process of a capacitor formed by contacting surfaces,and is found consistent with the experimental measurements.The experiments further indicate that,when discharging occurs,it has no influence on the charging process of the initially negatively charged surface,but can greatly change the charging of the initially positively charged surface,on which the potential will increase initially,soon begin to decrease,and eventually reach a stable value.Such a significant difference in the potential variation when discharging occurs can be attributed to the huge difference in mass between electrons and positive ions produced in the discharging process.The present work may offer a new perspective for understanding the electron transfer dynamics in TE and may provide potential applications in numerous fields involving TE.展开更多
The use of water resources for energy generation has become increasingly prevalent,encompassing the conversion of kinetic energy from streams,tides,and waves into renewable electrical power.Water energy sources offer ...The use of water resources for energy generation has become increasingly prevalent,encompassing the conversion of kinetic energy from streams,tides,and waves into renewable electrical power.Water energy sources offer numerous benefits,including widespread availability,stability,and the absence of carbon dioxide and other greenhouse gas emissions,making them a clean and environmentally friendly form of energy.In this work,we develop a droplet-based liquid-solid triboelectric nanogenerator(LS-TENG)using sophisticatedly designed inflatable columnar structures with inner and outer dual-electrodes.This device can be utilized to harvest both the internal droplet-rolling mechanical energy and the external droplet-falling mechanical energy,capable of being assembled into various structures for versatile applications.The design incorporates a combined structure of both internal and external TENG to optimize output performance via multiple energy harvesting strategies.The internal structure features a dual-electrode columnar-shaped LS-TENG,designed to harvest fluid kinetic energy from water droplets.By leveraging the back-and-forth motion of a small amount of water within the air column,mechanical energy can be readily collected,achieving a maximum mass power density of 9.02 W·Kg^(−1)and an energy conversion efficiency of 10.358%.The external component is a droplet-based LS-TENG,which utilizes a double-layer capacitor switch effect elucidated with an equivalent circuit model.Remarkably,without the need for pre-charging,a single droplet can generate over 140 V of high voltage,achieving a maximum power density of 7.35 W·m^(−2)and an energy conversion efficiency of 22.058%.The combined LS-TENG with a sophisticated inflatable columnar structure can simultaneously collect multiple types of energy with high efficacy,exhibiting great significance in potential applications such as TENG aeration rollers,inflatable lifejacket,wind energy harvesting,TENG tents,and green houses.展开更多
UV is a high-energy electromagnetic radiation that has been widely used in industrial production and the scientific research domain. In this work, a deep UV light emission was obtained using triboelectrification induc...UV is a high-energy electromagnetic radiation that has been widely used in industrial production and the scientific research domain. In this work, a deep UV light emission was obtained using triboelectrification induced plasma discharge without any extra power supply. By a mechanical friction between polymer and quartz glass, the triboelectric charges cause a changing electric field, which may bring plasma discharge of low pressure gas （Ar-Hg） and give out 253.7 nm irradiation. The UV light caused by continuous friction can excite a trichromatic phosphor and afford a bright white light emission. A UV sterilization experiment shows that -98% of Escherichia coil can be killed in 30 min by UV irradiation, which reveals that a self-powered sterilization apparatus with good sterilization effect was fabricated. This work provides a novel design to fabricate a self- powered UV light emitting device using low-frequency mechanical friction and realizes the coupling of triboelectrificafion and plasma luminescence, which may further expand the application of UV light in special circumstances.展开更多
Contact electrification(CE)is one of the most important physical phenomena within the realm of surface science,with a history spanning over 2,600 years.Although numerous experiments have been conducted to detect CE an...Contact electrification(CE)is one of the most important physical phenomena within the realm of surface science,with a history spanning over 2,600 years.Although numerous experiments have been conducted to detect CE and theories regarding electron,ion,and material transfer have been proposed,the mechanism of CE remains a subject of ongoing debate and continues to intrigue scientists.A key issue in CE studies is accurately measuring the charge transfer in various situations.The development of charge transfer measurements has consistently led to a deeper understanding of CE.In this review,we explore the field of CEs,focusing on methods for measuring charge transfer.The introduction of six experimental methods from macroscopic to microscopic and first-principles calculations for CE studies aims to promote their proper use and inspire the design of new methods.Moreover,we highlight the shortcomings of the present research approach and provide a perspective on future methodological developments.展开更多
Long-term observation of the triboelectric effect has not only proved the feasibility of many novel and useful tribo-devices(e.g., triboelectric nanogenerators), but also constantly motivated the exploration of its my...Long-term observation of the triboelectric effect has not only proved the feasibility of many novel and useful tribo-devices(e.g., triboelectric nanogenerators), but also constantly motivated the exploration of its mysterious nature. In the pursuit of a comprehensive understanding of how the triboelectric process works, a more accurate description of the triboelectric effect and its related parameters and factors is urgently required. This review critically goes through the fundamental theories and basic principles governing the triboelectric process. By investigating the difference between each charging media, the electron, ion, and material transfer is discussed and the theoretical deduction in the past decades is provided. With the information from the triboelectric series, interesting phenomena including cyclic triboelectric sequence and asymmetric triboelectrification are precisely analyzed. Then, the interaction between the tribo-system and its operational environment is analyzed, and a fundamental description of its effects on the triboelectric process and results is summarized. In brief, this review is expected to provide a strong understanding of the triboelectric effect in a more rigorous mathematical and physical sense.展开更多
The process of charge transfer based on triboelectrification （TE） and contact electrification （CE） has been recently utilized as the basis for a new and promising energy harvesting technology, i.e., triboelectric ...The process of charge transfer based on triboelectrification （TE） and contact electrification （CE） has been recently utilized as the basis for a new and promising energy harvesting technology, i.e., triboelectric nanogenerators, as well as self- powered sensors and systems. The electrostatic charge transfer between two surfaces can occur in both the TE and the CE modes depending on the involvement of relative sliding friction. Does the sliding behavior in TE induce any fundamental difference in the charge transfer from the CE？ Few studies are available on this comparison because of the challenges in ruling out the effect of the contact area using traditional macro-scale characterization methods. This paper provides the first study on the fundamental differences in CE and TE at the nanoscale based on scanning probe microscopic methods. A quantitative comparison of the two processes at equivalent contact time and force is provided, and the results suggest that the charge transfer from TE is much faster than that from CE, but the saturation value of the transferred charge density is the same. The measured frictional energy dissipation of -11 eV when the tip scans over distance of I A sheds light on a potential mechanism： The friction may facilitate the charge transfer process via electronic excitation. These results provide fundamental guidance for the selection of materials and device structures to enable the TE or the CE in different applications; the CE mode is favorable for frequent moderate contact such as vibration energy harvesting and the TE mode is favorable for instant movement such as harvesting of energy from human walking.展开更多
A new self-powered active gas sensor for realtime monitoring of automotive exhaust gas was devised.The pipe-shaped device was fabricated from polydimethylsiloxane/polypyrrole(PDMS/Ppy)triboelectric gas-sensing unit ar...A new self-powered active gas sensor for realtime monitoring of automotive exhaust gas was devised.The pipe-shaped device was fabricated from polydimethylsiloxane/polypyrrole(PDMS/Ppy)triboelectric gas-sensing unit arrays.The gas-sensing units can actively convert the mechanical energy of gas flow into a triboelectric current.The output current signal depends on the species and concentrations of the target chemical gases(CO,NH3,NO)in the gas flow,and thus can be used as a sensing signal.The device consists of seven gas-sensing units with different Ppy derivatives.As the different sensing units respond to the gases in different ways,the device can differentiate between gas species.The working mechanism is attributed to the coupling effect between the triboelectric effect of PDMS/Ppy and the gas-sensing properties of Ppy.The device can be installed in the tailpipe of an automobile,and can thus analyze the exhaust gas in real time without the need for any external electrical power.The results of the present study spur a new research direction for the development of automotive exhaust gas monitoring systems,thus playing an important role in the detection of air pollution.展开更多
A mechanism-oriented model is proposed here as a speculative but robust attempt to understand whether there might be any increased risk of electrostatically induced contamination,with relevant consequences from the ep...A mechanism-oriented model is proposed here as a speculative but robust attempt to understand whether there might be any increased risk of electrostatically induced contamination,with relevant consequences from the epidemiological viewpoint.This could also be the case for the COVID-19 spreading because an amount of micro-sized droplet nuclei,often carrying net electric charge,are expected to be electro-dynamically involved in a physical process originated by the natural and unperceivable static electrification of human beings.The effects of the triboelectric charging have long been successfully tested because the phenomenon under examination is also implied in the genesis of the electrostatic discharge(ESD),a demanding key objective in the special context of electromagnetic compatibility(EMC).Therefore,the ultimate purpose of this technical paper is to provide valuable insights into infection control,building on what is already being done for maintaining static-safe environments.The stature of the applied model can be further appreciated because some currently observed climate-dependent and sexlinked different vulnerabilities to COVID-19 are critically examined by unique sound arguments.These ultimately focus attention on ambient relative humidity and worn shoes,the latter differing for typology,size and material,for their integrated control of the inadvertent human aptitude to buildup tribocharges.These would appear as a dreadful prerequisite for charge bearing droplets in the airborne state to be efficiently attracted/repelled according to the described electrostatic mechanism.展开更多
基金supported by the National Natural Science Foundation of China(No. 50921002)the Key Laboratory of Coal Processing and Efficient Utilization,the Ministry of Education of China(No.CPEUKF08-05).
文摘Chemical conditioning was used to modify the triboelectrification of coal and mineral particles.The chemicals tested included starch,lignin,kerosene,ethanol,acetic acid,salicylic acid,sodium oleate,Sodium Hexametaphosphate(SH),sodium silicate, Sodium Dodecylbenzenesulfonate(SDBS),Sodium Bicarbonate(SB) and ammonia.A high-speed,dry mixing method was employed.The charge-to-mass ratio of the coal and mineral samples,both untreated and treated,was tested using a Faraday cup. Dielectric constants were determined by measuring capacitance.It is found that the selectivity of the additives toward coal or minerals is not consistent.Salicylic acid is the optimal additive to enhance the triboelectrification performance of coal samples.Starch, lignin and sodium oleate are suitable for removal of pyrite.SH,sodium silicate,SDBS,SB and ammonia are suitable additives for the removal of ash-forming minerals.
基金supported by the National Natural Science Foundation of China(Nos.12072191 and 51875343)the Open Fund of Space Drive and Manipulation Mechanism Laboratory(No.BICE-SDMML-2022-04)the Science and Technology Commission of Shanghai Municipality(No.24DZ2307500).
文摘The triboelectric effect,known since ancient Greece,is the accumulation of electric charges due to electron transfer when materials contact and separate.With technological advancements,the triboelectric effect has been applied in energy harvesting equipment,sensors,and smart devices,including triboelectric nanogenerators(TENGs).This effect shows potential for sustainable energy and next-generation intelligent systems.Triboelectric systems,as a type of tribological system,require state monitoring,behavior prediction,and system optimization.Tribo-informatics is an interdisciplinary field that combines tribology and informatics.By clarifying information representations and flows within tribological systems,tribo-informatics addresses the connections between physical tribological systems and embedded information systems.With a focus on the triboelectric effect,this paper proposes a method for information representation in triboelectric systems from a tribo-informatics perspective and suggests a research approach based on tribo-informatics to achieve research goals.The aim is to enable researchers to collect,process,and analyze tribological information more effectively to achieve specific research objectives.
基金supported by the National Natural Science Foundation of China(52375166).
文摘Although triboelectrification(TE)is essential in many industrial and scientific fields,its charge transfer mechanisms are still not fully understood.In this paper,the charging-induced electric potential on the friction surface and the discharging-induced light emission from the contact region during sliding frictions between insulators have been observed simultaneously.The results show that,in the absence of discharging,the temporal variations of surface potential at all the contact points are almost the same,experiencing a rapid growth in the initial stage,followed by a slow growth,and eventually reaching a stable value.To explain such a dynamics of electron transfer,a theoretical expression for the temporal evolution of the surface potential during TE process is proposed by considering the electron transfer as the charging process of a capacitor formed by contacting surfaces,and is found consistent with the experimental measurements.The experiments further indicate that,when discharging occurs,it has no influence on the charging process of the initially negatively charged surface,but can greatly change the charging of the initially positively charged surface,on which the potential will increase initially,soon begin to decrease,and eventually reach a stable value.Such a significant difference in the potential variation when discharging occurs can be attributed to the huge difference in mass between electrons and positive ions produced in the discharging process.The present work may offer a new perspective for understanding the electron transfer dynamics in TE and may provide potential applications in numerous fields involving TE.
基金supported by the National Key Research and Development Program of China(2023YFB3208102,2021YFB3200304)the National Natural Science Foundation of China(52073031)+2 种基金Beijing Nova Program(Z211100002121148)Fundamental Research Funds for the Central Universities(E0EG6801X2)the‘Hundred Talents Program’of the Chinese Academy of Sciences.
文摘The use of water resources for energy generation has become increasingly prevalent,encompassing the conversion of kinetic energy from streams,tides,and waves into renewable electrical power.Water energy sources offer numerous benefits,including widespread availability,stability,and the absence of carbon dioxide and other greenhouse gas emissions,making them a clean and environmentally friendly form of energy.In this work,we develop a droplet-based liquid-solid triboelectric nanogenerator(LS-TENG)using sophisticatedly designed inflatable columnar structures with inner and outer dual-electrodes.This device can be utilized to harvest both the internal droplet-rolling mechanical energy and the external droplet-falling mechanical energy,capable of being assembled into various structures for versatile applications.The design incorporates a combined structure of both internal and external TENG to optimize output performance via multiple energy harvesting strategies.The internal structure features a dual-electrode columnar-shaped LS-TENG,designed to harvest fluid kinetic energy from water droplets.By leveraging the back-and-forth motion of a small amount of water within the air column,mechanical energy can be readily collected,achieving a maximum mass power density of 9.02 W·Kg^(−1)and an energy conversion efficiency of 10.358%.The external component is a droplet-based LS-TENG,which utilizes a double-layer capacitor switch effect elucidated with an equivalent circuit model.Remarkably,without the need for pre-charging,a single droplet can generate over 140 V of high voltage,achieving a maximum power density of 7.35 W·m^(−2)and an energy conversion efficiency of 22.058%.The combined LS-TENG with a sophisticated inflatable columnar structure can simultaneously collect multiple types of energy with high efficacy,exhibiting great significance in potential applications such as TENG aeration rollers,inflatable lifejacket,wind energy harvesting,TENG tents,and green houses.
文摘UV is a high-energy electromagnetic radiation that has been widely used in industrial production and the scientific research domain. In this work, a deep UV light emission was obtained using triboelectrification induced plasma discharge without any extra power supply. By a mechanical friction between polymer and quartz glass, the triboelectric charges cause a changing electric field, which may bring plasma discharge of low pressure gas （Ar-Hg） and give out 253.7 nm irradiation. The UV light caused by continuous friction can excite a trichromatic phosphor and afford a bright white light emission. A UV sterilization experiment shows that -98% of Escherichia coil can be killed in 30 min by UV irradiation, which reveals that a self-powered sterilization apparatus with good sterilization effect was fabricated. This work provides a novel design to fabricate a self- powered UV light emitting device using low-frequency mechanical friction and realizes the coupling of triboelectrificafion and plasma luminescence, which may further expand the application of UV light in special circumstances.
基金supported by the National Natural Science Foundation of China(Nos.52375213,52005044,and 52450006).
文摘Contact electrification(CE)is one of the most important physical phenomena within the realm of surface science,with a history spanning over 2,600 years.Although numerous experiments have been conducted to detect CE and theories regarding electron,ion,and material transfer have been proposed,the mechanism of CE remains a subject of ongoing debate and continues to intrigue scientists.A key issue in CE studies is accurately measuring the charge transfer in various situations.The development of charge transfer measurements has consistently led to a deeper understanding of CE.In this review,we explore the field of CEs,focusing on methods for measuring charge transfer.The introduction of six experimental methods from macroscopic to microscopic and first-principles calculations for CE studies aims to promote their proper use and inspire the design of new methods.Moreover,we highlight the shortcomings of the present research approach and provide a perspective on future methodological developments.
基金supported by the National Natural Science Foundation of China (No.51575340)State Key Laboratory of Solid Lubrication (No.LSL-1604)the Shanghai Academy of Space Technology-Shanghai Jiao Tong University Joint Research Center of Advanced Aerospace Technology (USCAST2016-13)
文摘Long-term observation of the triboelectric effect has not only proved the feasibility of many novel and useful tribo-devices(e.g., triboelectric nanogenerators), but also constantly motivated the exploration of its mysterious nature. In the pursuit of a comprehensive understanding of how the triboelectric process works, a more accurate description of the triboelectric effect and its related parameters and factors is urgently required. This review critically goes through the fundamental theories and basic principles governing the triboelectric process. By investigating the difference between each charging media, the electron, ion, and material transfer is discussed and the theoretical deduction in the past decades is provided. With the information from the triboelectric series, interesting phenomena including cyclic triboelectric sequence and asymmetric triboelectrification are precisely analyzed. Then, the interaction between the tribo-system and its operational environment is analyzed, and a fundamental description of its effects on the triboelectric process and results is summarized. In brief, this review is expected to provide a strong understanding of the triboelectric effect in a more rigorous mathematical and physical sense.
基金Research was supported by U.S. Department of Energy, Office of Basic Energy Sciences （No. DE-FG02- 07ER46394） and the National Science Foundation （No. DMR-1505319）. We also would like to express our sincere appreciation to Dr. Ricardo Garcia for the insightful discussion on modeling and calculation of the dynamic motion of the cantilever in tapping mode AFM.
文摘The process of charge transfer based on triboelectrification （TE） and contact electrification （CE） has been recently utilized as the basis for a new and promising energy harvesting technology, i.e., triboelectric nanogenerators, as well as self- powered sensors and systems. The electrostatic charge transfer between two surfaces can occur in both the TE and the CE modes depending on the involvement of relative sliding friction. Does the sliding behavior in TE induce any fundamental difference in the charge transfer from the CE？ Few studies are available on this comparison because of the challenges in ruling out the effect of the contact area using traditional macro-scale characterization methods. This paper provides the first study on the fundamental differences in CE and TE at the nanoscale based on scanning probe microscopic methods. A quantitative comparison of the two processes at equivalent contact time and force is provided, and the results suggest that the charge transfer from TE is much faster than that from CE, but the saturation value of the transferred charge density is the same. The measured frictional energy dissipation of -11 eV when the tip scans over distance of I A sheds light on a potential mechanism： The friction may facilitate the charge transfer process via electronic excitation. These results provide fundamental guidance for the selection of materials and device structures to enable the TE or the CE in different applications; the CE mode is favorable for frequent moderate contact such as vibration energy harvesting and the TE mode is favorable for instant movement such as harvesting of energy from human walking.
基金supported by the National Natural Science Foundation of China (11674048)the Fundamental Research Funds for the Central Universities (N170505001 and N160502002)the Program for Shenyang Youth Science and Technology Innovation Talents (RC170269)
文摘A new self-powered active gas sensor for realtime monitoring of automotive exhaust gas was devised.The pipe-shaped device was fabricated from polydimethylsiloxane/polypyrrole(PDMS/Ppy)triboelectric gas-sensing unit arrays.The gas-sensing units can actively convert the mechanical energy of gas flow into a triboelectric current.The output current signal depends on the species and concentrations of the target chemical gases(CO,NH3,NO)in the gas flow,and thus can be used as a sensing signal.The device consists of seven gas-sensing units with different Ppy derivatives.As the different sensing units respond to the gases in different ways,the device can differentiate between gas species.The working mechanism is attributed to the coupling effect between the triboelectric effect of PDMS/Ppy and the gas-sensing properties of Ppy.The device can be installed in the tailpipe of an automobile,and can thus analyze the exhaust gas in real time without the need for any external electrical power.The results of the present study spur a new research direction for the development of automotive exhaust gas monitoring systems,thus playing an important role in the detection of air pollution.
文摘A mechanism-oriented model is proposed here as a speculative but robust attempt to understand whether there might be any increased risk of electrostatically induced contamination,with relevant consequences from the epidemiological viewpoint.This could also be the case for the COVID-19 spreading because an amount of micro-sized droplet nuclei,often carrying net electric charge,are expected to be electro-dynamically involved in a physical process originated by the natural and unperceivable static electrification of human beings.The effects of the triboelectric charging have long been successfully tested because the phenomenon under examination is also implied in the genesis of the electrostatic discharge(ESD),a demanding key objective in the special context of electromagnetic compatibility(EMC).Therefore,the ultimate purpose of this technical paper is to provide valuable insights into infection control,building on what is already being done for maintaining static-safe environments.The stature of the applied model can be further appreciated because some currently observed climate-dependent and sexlinked different vulnerabilities to COVID-19 are critically examined by unique sound arguments.These ultimately focus attention on ambient relative humidity and worn shoes,the latter differing for typology,size and material,for their integrated control of the inadvertent human aptitude to buildup tribocharges.These would appear as a dreadful prerequisite for charge bearing droplets in the airborne state to be efficiently attracted/repelled according to the described electrostatic mechanism.
