Human skin exhibits a remarkable capability to perceive contact forces and environmental temperatures,providing complex information that is essential for its subtle control.Despite recent advancements in soft tactile ...Human skin exhibits a remarkable capability to perceive contact forces and environmental temperatures,providing complex information that is essential for its subtle control.Despite recent advancements in soft tactile sensors,accurately decoupling signals—specifically separating forces from directional orientation and temperature—remains a challenge thus resulting in failure to meet the advanced application requirements of robots.This study proposes,F3T,a multilayer soft sensor unit designed to achieve isolated measurements and mathematical decoupling of normal pressure,omnidirectional tangential forces,and temperature.We developed a circular coaxial magnetic film featuring a floating mount multilayer capacitor that facilitated the physical decoupling of normal and tangential forces in all directions.Additionally,we incorporated an ion gel-based temperature-sensing film into the tactile sensor.The proposed sensor was resilient to external pressures and deformations,and could measure temperature and significantly eliminate capacitor errors induced by environmental temperature changes.In conclusion,our novel design allowed for the decoupled measurement of multiple signals,laying the foundation for advancements in high-level robotic motion control,autonomous decision-making,and task planning.展开更多
In the past decade,the global industry and research attentions on intelligent skin-like electronics have boosted their applications in diverse fields including human healthcare,Internet of Things,human–machine interf...In the past decade,the global industry and research attentions on intelligent skin-like electronics have boosted their applications in diverse fields including human healthcare,Internet of Things,human–machine interfaces,artificial intelligence and soft robotics.Among them,flexible humidity sensors play a vital role in noncontact measurements relying on the unique property of rapid response to humidity change.This work presents an overview of recent advances in flexible humidity sensors using various active functional materials for contactless monitoring.Four categories of humidity sensors are highlighted based on resistive,capacitive,impedance-type and voltage-type working mechanisms.Furthermore,typical strategies including chemical doping,structural design and Joule heating are introduced to enhance the performance of humidity sensors.Drawing on the noncontact perception capability,human/plant healthcare management,human-machine interactions as well as integrated humidity sensor-based feedback systems are presented.The burgeoning innovations in this research field will benefit human society,especially during the COVID-19 epidemic,where cross-infection should be averted and contactless sensation is highly desired.展开更多
Micro/nanorobots have long been expected to reach all parts of the human body through blood vessels for medical treatment or surgery.However,in the current stage,it is still challenging to drive a microrobot in viscou...Micro/nanorobots have long been expected to reach all parts of the human body through blood vessels for medical treatment or surgery.However,in the current stage,it is still challenging to drive a microrobot in viscous media at high speed and difficult to observe the shape and position of a single microrobot once it enters the bloodstream.Here,we propose a new micro-rocket robot and an all-optic driving and imaging system that can actuate and track it in blood with microscale resolution.To achieve a high driving force,we engineer the microrobot to have a rocket-like tripletube structure.Owing to the interface design,the 3D-printed micro-rocket can reach a moving speed of 2.8 mm/s(62 body lengths per second)under near-infrared light actuation in a blood-mimicking viscous glycerol solution.We also show that the micro-rocket robot is successfully tracked at a 3.2-μm resolution with an optical-resolution photoacoustic microscope in blood.This work paves the way for microrobot design,actuation,and tracking in the blood environment,which may broaden the scope of microrobotic applications in the biomedical field.展开更多
A series of robust metallo-aerogels are readily fabricated by pyrolysis of xerogels derived from chitosan-metal(M=Fe,Co,Ni)hydrogels.Owing to the strong coordination between metal ions and the functional groups(NH2 an...A series of robust metallo-aerogels are readily fabricated by pyrolysis of xerogels derived from chitosan-metal(M=Fe,Co,Ni)hydrogels.Owing to the strong coordination between metal ions and the functional groups(NH2 and OH)of chitosan,metallo-aerogels consisting of encapsulated metal-nanoparticles(MNPs)by graphite shells were obtained,as supported by various characterizations including high-resolution transmission electron microscope(HR-TEM),X-ray diffraction(XRD),and Raman.The resulting metalloaerogels could be functioned as highly stable,efficient and selective nanocatalysts towards the hydrogenation of nitroarenes to amines at low catalyst loading(1.2 mol.%-2.4 mol.%).Remarkably,the metallo-aerogels could be reused for more than 30 runs without obvious loss of activity and selectivity.These distinguished performances were attributed to the graphitic shells formed during the pyrolysis,which hampered the possible aggregation of MNPs,prevented metal leaching and increased their stability.展开更多
Developing non-precious metal catalysts to selectively reduce functionalized nitroarenes with high efficiency is urgently desirable for the production of value-added amines.Herein,we report a novel,efficient,anti-pois...Developing non-precious metal catalysts to selectively reduce functionalized nitroarenes with high efficiency is urgently desirable for the production of value-added amines.Herein,we report a novel,efficient,anti-poisoning single-atom cobalt catalyst(Co-NAC)for the highly selective hydrogenation of the nitro to amino group for nitroarenes baring various functional groups,including vinyl,cyano,and halogen.Using a combination of structure characterization techniques,we have confirmed that the cobalt species are predominantly present in the form of four-coordinated Co single sites anchored on nitrogen-assembly carbon(NAC)as the ordered mesoporous support.Co-NAC catalysts enable the full conversion and>99%selectivity with molecular H2 as a green reductant under mild conditions(80℃,2 MPa H2).As for the selective hydrogenation of 3-nitrostyrene,Co-NAC catalyst affords high catalytic productivity(19.7 h-1),which is superior to the cobalt nanoparticles(NPs)catalysts and most of the recently reported Co-based catalysts.This is attributed to the highly accessible atomically-dispersed Co active sites,the high surface area with ordered-mesoporous morphology and the prominent high content of nitrogen dopants.Notably,Co-NAC catalyst displays resistance towards sulfur-containing poisons(20 equivalents)and strong non-oxidizing acid(8 M),showing great potential for continuous application in the chemical industry.展开更多
In situ scanning electron microscope(SEM)characterization have enabled the stretching,compression,and bending of micro/nanomaterials and have greatly expanded our understanding of small-scale phenomena.However,as one ...In situ scanning electron microscope(SEM)characterization have enabled the stretching,compression,and bending of micro/nanomaterials and have greatly expanded our understanding of small-scale phenomena.However,as one of the fundamental approaches for material analytics,torsion tests at a small scale remain a major challenge due to the lack of an ultrahigh precise torque sensor and the delicate sample assembly strategy.Herein,we present a microelectromechanical resonant torque sensor with an ultrahigh resolution of up to 4.78 fN∙m within an ultrawide dynamic range of 123 dB.Moreover,we propose a nanorobotic system to realize the precise assembly of microscale specimens with nanoscale positioning accuracy and to conduct repeatable in situ pure torsion tests for the first time.As a demonstration,we characterized the mechanical properties of Si microbeams through torsion tests and found that these microbeams were five-fold stronger than their bulk counterparts.The proposed torsion characterization system pushes the limit of mechanical torsion tests,overcomes the deficiencies in current in situ characterization techniques,and expands our knowledge regarding the behavior of micro/nanomaterials at various loads,which is expected to have significant implications for the eventual development and implementation of materials science.展开更多
Surface acoustic wave(SAW)tweezers are a promising multifunctional micromanipulation method that controls microscale targets via patterned acoustic fields.Owing to their device structure and bonding process,most SAW t...Surface acoustic wave(SAW)tweezers are a promising multifunctional micromanipulation method that controls microscale targets via patterned acoustic fields.Owing to their device structure and bonding process,most SAW tweezers have limitations in terms of controlling the position and motion of the acoustic traps,as they generate an acoustic field with a fixed region and adjust the manipulation effects via signal modulation.To address this challenge,we propose movable SAW tweezers with a multilayer structure,achieving dynamic control of their wave field and acoustic trap positions;we demonstrate their precise manipulation functions,such as translation,in-plane rotation,out-of-plane rotation,and cluster formation,on a wide spectrum of samples,including particles,bubbles,droplets,cells,and microorganisms.Our method not only improves the degree of freedom and working range of SAW tweezers but also allows for precise and selective manipulation of microtargets via microtools and localized wavefields.Owing to their flexibility,versatility,and biocompatibility,the movable SAW tweezers can be a practical platform for achieving arbitrary manipulation of microscale targets and have the potential to play significant roles in biomedical microrobotics.展开更多
基金support by Hong Kong RGC General Research Fund(16217824,16213825,16203923,and 16217824)National Natural Science Foundation of China(N_HKUST638/23)+1 种基金Research Grants Council Joint Research Scheme(62361166630)Guangdong Basic and Applied Basic Research Foundation(2023B1515130007).
文摘Human skin exhibits a remarkable capability to perceive contact forces and environmental temperatures,providing complex information that is essential for its subtle control.Despite recent advancements in soft tactile sensors,accurately decoupling signals—specifically separating forces from directional orientation and temperature—remains a challenge thus resulting in failure to meet the advanced application requirements of robots.This study proposes,F3T,a multilayer soft sensor unit designed to achieve isolated measurements and mathematical decoupling of normal pressure,omnidirectional tangential forces,and temperature.We developed a circular coaxial magnetic film featuring a floating mount multilayer capacitor that facilitated the physical decoupling of normal and tangential forces in all directions.Additionally,we incorporated an ion gel-based temperature-sensing film into the tactile sensor.The proposed sensor was resilient to external pressures and deformations,and could measure temperature and significantly eliminate capacitor errors induced by environmental temperature changes.In conclusion,our novel design allowed for the decoupled measurement of multiple signals,laying the foundation for advancements in high-level robotic motion control,autonomous decision-making,and task planning.
基金supported by the National Science and Technology Innovation 2030 Major Project(Grant No.2022ZD0208601)the National Natural Science Foundation of China(Grant No.52105593 and 51975513)the Natural Science Foundation of Zhejiang Province,China(No.LR20E050003)。
文摘In the past decade,the global industry and research attentions on intelligent skin-like electronics have boosted their applications in diverse fields including human healthcare,Internet of Things,human–machine interfaces,artificial intelligence and soft robotics.Among them,flexible humidity sensors play a vital role in noncontact measurements relying on the unique property of rapid response to humidity change.This work presents an overview of recent advances in flexible humidity sensors using various active functional materials for contactless monitoring.Four categories of humidity sensors are highlighted based on resistive,capacitive,impedance-type and voltage-type working mechanisms.Furthermore,typical strategies including chemical doping,structural design and Joule heating are introduced to enhance the performance of humidity sensors.Drawing on the noncontact perception capability,human/plant healthcare management,human-machine interactions as well as integrated humidity sensor-based feedback systems are presented.The burgeoning innovations in this research field will benefit human society,especially during the COVID-19 epidemic,where cross-infection should be averted and contactless sensation is highly desired.
基金supported by the National Natural Science Foundation of China(61922093,81627805,61805102)Research Grants Council of the Hong Kong Special Administrative Region(21205016,11215817,11101618)Science Technology and Innovation Commission of Shenzhen Municipality,China(JCYJ20170413140519030).
文摘Micro/nanorobots have long been expected to reach all parts of the human body through blood vessels for medical treatment or surgery.However,in the current stage,it is still challenging to drive a microrobot in viscous media at high speed and difficult to observe the shape and position of a single microrobot once it enters the bloodstream.Here,we propose a new micro-rocket robot and an all-optic driving and imaging system that can actuate and track it in blood with microscale resolution.To achieve a high driving force,we engineer the microrobot to have a rocket-like tripletube structure.Owing to the interface design,the 3D-printed micro-rocket can reach a moving speed of 2.8 mm/s(62 body lengths per second)under near-infrared light actuation in a blood-mimicking viscous glycerol solution.We also show that the micro-rocket robot is successfully tracked at a 3.2-μm resolution with an optical-resolution photoacoustic microscope in blood.This work paves the way for microrobot design,actuation,and tracking in the blood environment,which may broaden the scope of microrobotic applications in the biomedical field.
基金the National Key R&D Program of China(No.2016YFA0202902)the National Natural Science Foundation of China(Nos.21861132002,21871059,21572036)the Department of Chemistry,Fudan University is gratefully acknowledged.
文摘A series of robust metallo-aerogels are readily fabricated by pyrolysis of xerogels derived from chitosan-metal(M=Fe,Co,Ni)hydrogels.Owing to the strong coordination between metal ions and the functional groups(NH2 and OH)of chitosan,metallo-aerogels consisting of encapsulated metal-nanoparticles(MNPs)by graphite shells were obtained,as supported by various characterizations including high-resolution transmission electron microscope(HR-TEM),X-ray diffraction(XRD),and Raman.The resulting metalloaerogels could be functioned as highly stable,efficient and selective nanocatalysts towards the hydrogenation of nitroarenes to amines at low catalyst loading(1.2 mol.%-2.4 mol.%).Remarkably,the metallo-aerogels could be reused for more than 30 runs without obvious loss of activity and selectivity.These distinguished performances were attributed to the graphitic shells formed during the pyrolysis,which hampered the possible aggregation of MNPs,prevented metal leaching and increased their stability.
基金supported by the National Key R&D Program of China(No.2016YFA0202900)the National Natural Science Foundation of China(Nos.21878266,22078288,and 22108243)+4 种基金L.Q.and Y.T.L.were supported by the U.S.Department of Energy(DOE),Office of Basic Energy Sciences,Division of Chemical Sciences,Geosciences,and BiosciencesThe Ames Laboratory is operated for the U.S.DOE by Iowa State University under Contract No.DE-AC02-07CH11358W.Y.H.,J.Q.Y.,and X.W.thank the support from Iowa State University.F.D.L.thanks the Startup Fund from the University of Central Florida(UCF)S.H.X.thanks the support from the Preeminent Postdoctoral Program(P3)at UCFThis research used beamline 7-BM(QAS)of the National Synchrotron Light Source II,a U.S.Department of Energy(DOE)Office of Science User Facility operated for the DOE Office of Science by Brookhaven National Laboratory under Contract No.DE-SC0012704.
文摘Developing non-precious metal catalysts to selectively reduce functionalized nitroarenes with high efficiency is urgently desirable for the production of value-added amines.Herein,we report a novel,efficient,anti-poisoning single-atom cobalt catalyst(Co-NAC)for the highly selective hydrogenation of the nitro to amino group for nitroarenes baring various functional groups,including vinyl,cyano,and halogen.Using a combination of structure characterization techniques,we have confirmed that the cobalt species are predominantly present in the form of four-coordinated Co single sites anchored on nitrogen-assembly carbon(NAC)as the ordered mesoporous support.Co-NAC catalysts enable the full conversion and>99%selectivity with molecular H2 as a green reductant under mild conditions(80℃,2 MPa H2).As for the selective hydrogenation of 3-nitrostyrene,Co-NAC catalyst affords high catalytic productivity(19.7 h-1),which is superior to the cobalt nanoparticles(NPs)catalysts and most of the recently reported Co-based catalysts.This is attributed to the highly accessible atomically-dispersed Co active sites,the high surface area with ordered-mesoporous morphology and the prominent high content of nitrogen dopants.Notably,Co-NAC catalyst displays resistance towards sulfur-containing poisons(20 equivalents)and strong non-oxidizing acid(8 M),showing great potential for continuous application in the chemical industry.
基金supported by the National Key R&D Program of China(No.2018YFB2002303)the National Natural Science Foundation of China(Nos.52075432,61922093,U1813211,6207330)+1 种基金Hong Kong RGC General Research Fund CityU(11211720)ShenZhen(China)Key Basic Research Project(No.JCYJ20200109114827177).
文摘In situ scanning electron microscope(SEM)characterization have enabled the stretching,compression,and bending of micro/nanomaterials and have greatly expanded our understanding of small-scale phenomena.However,as one of the fundamental approaches for material analytics,torsion tests at a small scale remain a major challenge due to the lack of an ultrahigh precise torque sensor and the delicate sample assembly strategy.Herein,we present a microelectromechanical resonant torque sensor with an ultrahigh resolution of up to 4.78 fN∙m within an ultrawide dynamic range of 123 dB.Moreover,we propose a nanorobotic system to realize the precise assembly of microscale specimens with nanoscale positioning accuracy and to conduct repeatable in situ pure torsion tests for the first time.As a demonstration,we characterized the mechanical properties of Si microbeams through torsion tests and found that these microbeams were five-fold stronger than their bulk counterparts.The proposed torsion characterization system pushes the limit of mechanical torsion tests,overcomes the deficiencies in current in situ characterization techniques,and expands our knowledge regarding the behavior of micro/nanomaterials at various loads,which is expected to have significant implications for the eventual development and implementation of materials science.
基金This work is sponsored by the National Natural Science Foundation of China(Grant No.52375573)Shaanxi Province Postdoctoral Fund(Grant No.30102230006)+3 种基金the Basic Research Funds from Xidian University(Grant No.20103237933)the Fundamental Research Funds for the Central Universities(Grant No.XJSJ23123)Science and Technology on Applied Physical Chemistry Laboratory(Grant No.61426022220303)the Young Scientists Fund of the National Natural Science Foundation of China(Grant No.52405623)。
文摘Surface acoustic wave(SAW)tweezers are a promising multifunctional micromanipulation method that controls microscale targets via patterned acoustic fields.Owing to their device structure and bonding process,most SAW tweezers have limitations in terms of controlling the position and motion of the acoustic traps,as they generate an acoustic field with a fixed region and adjust the manipulation effects via signal modulation.To address this challenge,we propose movable SAW tweezers with a multilayer structure,achieving dynamic control of their wave field and acoustic trap positions;we demonstrate their precise manipulation functions,such as translation,in-plane rotation,out-of-plane rotation,and cluster formation,on a wide spectrum of samples,including particles,bubbles,droplets,cells,and microorganisms.Our method not only improves the degree of freedom and working range of SAW tweezers but also allows for precise and selective manipulation of microtargets via microtools and localized wavefields.Owing to their flexibility,versatility,and biocompatibility,the movable SAW tweezers can be a practical platform for achieving arbitrary manipulation of microscale targets and have the potential to play significant roles in biomedical microrobotics.
