Ultra-low friction is crucial for the anti-friction,anti-wear,and long-life operation of nanodevices.However,very few two-dimensional materials can achieve ultra-low friction,and they have some limitations in their ap...Ultra-low friction is crucial for the anti-friction,anti-wear,and long-life operation of nanodevices.However,very few two-dimensional materials can achieve ultra-low friction,and they have some limitations in their applications.Therefore,exploring novel materials with ultra-low friction properties is greatly significant.The emergence of ternary two-dimensional materials has opened new opportunities for nanoscale ultra-low friction.This study introduced nickel phosphorous trisulfide(NiPS3,referred to as NPS),a novel two-dimensional ternary material capable of achieving ultralow friction in a vacuum,into the large nanotribology family.Large-size and high-quality NPS crystals with up to 14 mm×6 mm×0.3 mm dimensions were grown using the chemical vapor transport method.The NPS nanosheets were obtained using mechanical exfoliation.The dependence of the NPS nanotribology on layer,velocity,and angle was systematically investigated using lateral force microscopy.Interestingly,the coefficient of friction(COF)of NPS with multilayers was decreased to about 0.0045 under 0.005 Pa vacuum condition(with load up to 767.8 nN),achieving the ultra-low friction state.The analysis of the frictional dissipation energy and adhesive forces showed that NPS with multilayers had minimum frictional dissipation energy and adhesive forces since the interlayer interactions were weak and the meniscus force was excluded under vacuum conditions.This study on the nanoscale friction of a ternary two-dimensional material lays a foundation for exploring the nanoscale friction and friction origin of other two-dimensional materials in the future.展开更多
The stable operation of friction pairs is one of the most critical factors to maintain the stable operation of mechanical equipment.The real-time monitoring of lubrication state of the friction pair is very important ...The stable operation of friction pairs is one of the most critical factors to maintain the stable operation of mechanical equipment.The real-time monitoring of lubrication state of the friction pair is very important to ensure the normal operation of machinery and realize early warning of wear failure,but it is also a big challenge.In this article,a new lubrication insitu monitoring system is designed,which can monitor the lubrication and wear state of friction pairs through triboelectrification.The current acquisition module and friction coefficient acquisition module are integrated into a high vacuum hydrodynamic oil film thickness measuring instrument to explore the intrinsic relationship between triboelectricity and friction coefficient curves.When severe wear occurs,the oil film at the interface of the friction pair is no longer complete,and the accumulated triboelectric charge at the interface of the friction pair breaks down the air and causes discharge,the friction current suddenly increases from nanoampere level to microampere level.The time node when discharge occurs at the steel ball interface is well consistent with the time node when the friction pair suffers serious wear.According to the corresponding relationship between the triboelectric current and the friction and wear status of the friction pair,an early wear warning monitoring system is designed to monitor the operating status of the friction pair in real time through triboelectric signals.When the mechanical friction pair is worn,the early warning system will send out sound and light alarm signals and send real-time warnings to the mobile terminal through the Internet of Things,providing a new and reliable method for real-time monitoring of friction and wear of grease-lubricated machinery.展开更多
Superlubricating materials can greatly reduce the energy consumed and economic losses by unnecessary friction.However,a long pre-running-in period is indispensable for achieving superlubricity;this leads to severe wea...Superlubricating materials can greatly reduce the energy consumed and economic losses by unnecessary friction.However,a long pre-running-in period is indispensable for achieving superlubricity;this leads to severe wear on the surface of friction pairs and has become one of the important factors in the wear of superlubricating materials.In this study,a polyethylene glycol-tannic acid complex green liquid lubricant(PEG10000-TA)was designed to achieve macroscale superlubricity with an ultrashort running-in period of 9 s under a contact pressure of up to 410 MPa,and the wear rate was only 1.19×10^(–8)mm^(3)·N^(−1)·m^(−1).This is the shortest running-in time required to achieve superlubricity in Si_(3)N_(4)/glass(SiO_(2)).The results show that the strong hydrogen bonds between PEG and TA molecules can significantly reduce the time required for the tribochemical reaction,allowing the lubricating material to reach the state of superlubrication rapidly.Furthermore,the strong hydrogen bond can share a large load while fixing free water molecules in the contact zone to reduce shear interaction.These findings will help advance the use of liquid superlubricity technology in industrial and biomedical.展开更多
With the continuous development of artificial intelligence,the demand for sensors with simple preparation and strong concealment continues to increase.However,most of the high-sensitivity sensors have complex manufact...With the continuous development of artificial intelligence,the demand for sensors with simple preparation and strong concealment continues to increase.However,most of the high-sensitivity sensors have complex manufacturing methods,high costs,and single functions.In this paper,a sensitive motion sensor based on the triboelectric interaction between a living plant and the human body was designed to detect the real-time movements of human beings and provide danger warning.A certain relationship exists between the triboelectric signal and the distance between the plant and the human body,with effective signals being detected in the range of 1.8 m.In addition,the triboelectric signal generated by each person is unique like a fingerprint,which can be used for biometrics.On the basis of the triboelectric signal,a wireless character entry warning system is designed.This sensor can not only send out a wireless warning signal at a specific distance but also allow one to receive the warning information synchronously on a mobile phone in real time.The wireless movement sensor receives signals through a living plant,and it has the characteristics of convenient use,strong concealment,and shielding difficulty.This sensor has the potential to be widely used in person recognition,danger warning,and motion monitoring.展开更多
Adsorption of drug powder is caused by triboelectrification on the surface of starch capsule during filling process.Furthermore,high wear rate and poor water lubricity also hinder the further practical applications of...Adsorption of drug powder is caused by triboelectrification on the surface of starch capsule during filling process.Furthermore,high wear rate and poor water lubricity also hinder the further practical applications of traditional starch capsule.To solve these problems,a glycerol-modified starch capsule with perfect anti-triboelec-trification and enhanced lubrication performance was fabricated.Hydrogen bond between glycerol and starch molecules could reduce the bound water content on the capsule surface and thus realizes anti-triboelectrification.By adding glycerol,a three-tier structure composed of starch-glycerol-water is formed through hydrogen bonding on the surface of the starch film,which has been proven to be favorable for lubrication performance.When 5% glycerol is added,the short-circuit current(I_(sc))of starch-based triboelectric nanogenerator(TENG)is reduced by 86%,and the wear volume of the starch film is reduced by 89%.Underwater lubrication condition,the lubrication performance of the starch-glycerol film can reach the super lubricated level with a friction coefficient of about 0.005.This work provides a new route to obtain modified starch capsules with improved anti-triboelectrification property,reduced wear rate and superlubricity property.展开更多
基金the financial support of the Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDB 0470103)the National Natural Science Foundation of China(Nos.52205230 and 52205233)+6 种基金the Key Research Program of the Chinese Academy of Sciences(No.ZDBS-ZRKJZ-TLC010)the Western Light Project of CAS(No.xbzg-zdsys-202118)the Major Science and Technology Projects in Gansu Province(No.22ZD6GA002)the Program for Taishan Scholars of Shandong Province(No.ts20190965)the Key Research and Development Program in Shandong Province(No.SYS202203)the Major Program of the Lanzhou Institute of Chemical Physics(LICP),CAS(No.ZYFZFX-5)the LICP Cooperation Foundation for Young Scholars(No.HZJJ23-7).
文摘Ultra-low friction is crucial for the anti-friction,anti-wear,and long-life operation of nanodevices.However,very few two-dimensional materials can achieve ultra-low friction,and they have some limitations in their applications.Therefore,exploring novel materials with ultra-low friction properties is greatly significant.The emergence of ternary two-dimensional materials has opened new opportunities for nanoscale ultra-low friction.This study introduced nickel phosphorous trisulfide(NiPS3,referred to as NPS),a novel two-dimensional ternary material capable of achieving ultralow friction in a vacuum,into the large nanotribology family.Large-size and high-quality NPS crystals with up to 14 mm×6 mm×0.3 mm dimensions were grown using the chemical vapor transport method.The NPS nanosheets were obtained using mechanical exfoliation.The dependence of the NPS nanotribology on layer,velocity,and angle was systematically investigated using lateral force microscopy.Interestingly,the coefficient of friction(COF)of NPS with multilayers was decreased to about 0.0045 under 0.005 Pa vacuum condition(with load up to 767.8 nN),achieving the ultra-low friction state.The analysis of the frictional dissipation energy and adhesive forces showed that NPS with multilayers had minimum frictional dissipation energy and adhesive forces since the interlayer interactions were weak and the meniscus force was excluded under vacuum conditions.This study on the nanoscale friction of a ternary two-dimensional material lays a foundation for exploring the nanoscale friction and friction origin of other two-dimensional materials in the future.
基金the financial support of the Strategic Priority Research Program of the Chinese Academy of Sciences(Grant No.XDB0470103)the Key Research and Development Program in Shandong Province(No.SYS202203)+5 种基金the National Natural Science Foundation of China(Nos.52275219,U21A2046,52205230,52205233)the Program for Taishan Scholars of Shandong Province(No.ts20190965)the Key Research Program of the Chinese Academy of Sciences(No.ZDBS-ZRKJZ-TLC010)the Western Light Project of CAS(No.xbzg-zdsys-202118)Major Science and Technology Projects in Gansu Province(No.22ZD6GA002)the Major Program of the Lanzhou Institute of Chemical Physics,CAS(No.ZYFZFX-5).
文摘The stable operation of friction pairs is one of the most critical factors to maintain the stable operation of mechanical equipment.The real-time monitoring of lubrication state of the friction pair is very important to ensure the normal operation of machinery and realize early warning of wear failure,but it is also a big challenge.In this article,a new lubrication insitu monitoring system is designed,which can monitor the lubrication and wear state of friction pairs through triboelectrification.The current acquisition module and friction coefficient acquisition module are integrated into a high vacuum hydrodynamic oil film thickness measuring instrument to explore the intrinsic relationship between triboelectricity and friction coefficient curves.When severe wear occurs,the oil film at the interface of the friction pair is no longer complete,and the accumulated triboelectric charge at the interface of the friction pair breaks down the air and causes discharge,the friction current suddenly increases from nanoampere level to microampere level.The time node when discharge occurs at the steel ball interface is well consistent with the time node when the friction pair suffers serious wear.According to the corresponding relationship between the triboelectric current and the friction and wear status of the friction pair,an early wear warning monitoring system is designed to monitor the operating status of the friction pair in real time through triboelectric signals.When the mechanical friction pair is worn,the early warning system will send out sound and light alarm signals and send real-time warnings to the mobile terminal through the Internet of Things,providing a new and reliable method for real-time monitoring of friction and wear of grease-lubricated machinery.
基金the National Natural Science Foundation of China(U21A2046,51905518)the Program for Taishan Scholars of Shandong Province(TS20190965)+4 种基金the National Key R&D Program of China(2020YFF0304600)the Innovation Leading Talents Program of Qingdao(19-3-2-23-zhc)in Chinathe Key Research Program of the Chinese Academy of Sciences(XDPB24)the Western Light Project of CAS(xbzg-zdsys-202118)the LICP Cooperation Foundation for Young Scholars(HZJJ21-03)for providing financial support.
文摘Superlubricating materials can greatly reduce the energy consumed and economic losses by unnecessary friction.However,a long pre-running-in period is indispensable for achieving superlubricity;this leads to severe wear on the surface of friction pairs and has become one of the important factors in the wear of superlubricating materials.In this study,a polyethylene glycol-tannic acid complex green liquid lubricant(PEG10000-TA)was designed to achieve macroscale superlubricity with an ultrashort running-in period of 9 s under a contact pressure of up to 410 MPa,and the wear rate was only 1.19×10^(–8)mm^(3)·N^(−1)·m^(−1).This is the shortest running-in time required to achieve superlubricity in Si_(3)N_(4)/glass(SiO_(2)).The results show that the strong hydrogen bonds between PEG and TA molecules can significantly reduce the time required for the tribochemical reaction,allowing the lubricating material to reach the state of superlubrication rapidly.Furthermore,the strong hydrogen bond can share a large load while fixing free water molecules in the contact zone to reduce shear interaction.These findings will help advance the use of liquid superlubricity technology in industrial and biomedical.
基金support from the NSFC(Nos.51905518,51722510)the Program for Taishan Scholar Foundation of Shandong Province(No.ts20190965)the Innovation Leading Talents Program of Qingdao(19-3-2-23-zhc)in China。
文摘With the continuous development of artificial intelligence,the demand for sensors with simple preparation and strong concealment continues to increase.However,most of the high-sensitivity sensors have complex manufacturing methods,high costs,and single functions.In this paper,a sensitive motion sensor based on the triboelectric interaction between a living plant and the human body was designed to detect the real-time movements of human beings and provide danger warning.A certain relationship exists between the triboelectric signal and the distance between the plant and the human body,with effective signals being detected in the range of 1.8 m.In addition,the triboelectric signal generated by each person is unique like a fingerprint,which can be used for biometrics.On the basis of the triboelectric signal,a wireless character entry warning system is designed.This sensor can not only send out a wireless warning signal at a specific distance but also allow one to receive the warning information synchronously on a mobile phone in real time.The wireless movement sensor receives signals through a living plant,and it has the characteristics of convenient use,strong concealment,and shielding difficulty.This sensor has the potential to be widely used in person recognition,danger warning,and motion monitoring.
基金financial support of the Program for Taishan Scholars of Shandong Province(No.ts20190965)the National Key Research and Development Program of China(2020YFF0304600)+1 种基金the National Natural Science Foundation of China(Grant No.51905518)the Innovation Leading Talents Program of Qingdao(19-3-2-23-zhc)in China.
文摘Adsorption of drug powder is caused by triboelectrification on the surface of starch capsule during filling process.Furthermore,high wear rate and poor water lubricity also hinder the further practical applications of traditional starch capsule.To solve these problems,a glycerol-modified starch capsule with perfect anti-triboelec-trification and enhanced lubrication performance was fabricated.Hydrogen bond between glycerol and starch molecules could reduce the bound water content on the capsule surface and thus realizes anti-triboelectrification.By adding glycerol,a three-tier structure composed of starch-glycerol-water is formed through hydrogen bonding on the surface of the starch film,which has been proven to be favorable for lubrication performance.When 5% glycerol is added,the short-circuit current(I_(sc))of starch-based triboelectric nanogenerator(TENG)is reduced by 86%,and the wear volume of the starch film is reduced by 89%.Underwater lubrication condition,the lubrication performance of the starch-glycerol film can reach the super lubricated level with a friction coefficient of about 0.005.This work provides a new route to obtain modified starch capsules with improved anti-triboelectrification property,reduced wear rate and superlubricity property.
