Tattoo electronics has attracted intensive interest in recent years due to its comfortable wearing and imperceivable sensing,and has been broadly applied in wearable healthcare and human-machine interface.However,the ...Tattoo electronics has attracted intensive interest in recent years due to its comfortable wearing and imperceivable sensing,and has been broadly applied in wearable healthcare and human-machine interface.However,the tattoo electrodes are mostly composed of metal films and conductive polymers.Two-dimensional(2D)materials,which are superior in conductivity and stability,are barely studied for electronic tattoos.Herein,we reported a novel electronic tattoo based on large-area Mo_(2)C film grown by chemical vapor deposition(CVD),and applied it to accurately and imperceivably acquire on-body electrophysiological signals and interface with robotics.High-quality Mo_(2)C film was obtained via optimizing the distribution of gas flow during CVD growth.According to the finite element simulation(FES),bottom surface of Cu foil covers more stable gas flow than the top surface,thus leading to more uniform Mo_(2)C film.The resulting Mo_(2)C film was transferred onto tattoo paper,showing a total thickness of~3μm,sheet resistance of 60-150Ω/sq,and skin-electrode impedance of~5×10^(5)Ω.Such thin Mo_(2)C electronic tattoo(MCET in short)can form conformal contact with skin and accurately record electrophysiological signals,including electromyography(EMG),electrocardiogram(ECG),and electrooculogram(EOG).These body signals collected by MCET can not only reflect the health status but also be transformed to control the robotics for human-machine interface.展开更多
A facile synthesis of the hierarchically porous cathode with Mo2C nanoparticles through the electrospinning technique and heat treatment is proposed. The carbonization temperature of the precursors is the key factor f...A facile synthesis of the hierarchically porous cathode with Mo2C nanoparticles through the electrospinning technique and heat treatment is proposed. The carbonization temperature of the precursors is the key factor for the formation of M02C nanoparticles on the carbon nanofibers （MCNFs）. Compared with the Mo2N nanoparticles embedded into N-doped carbon nanofibers film （MNNFs） and N-doped carbon nanofibers film （NFs）, the battery with MCNFs cathode is capable of operation with a high-capacity （10,509 mAhg-1 at 100 mAg-l）, a much reduced discharge-charge voltage gap, and a long-term life （124 cycles at 200 mA g-1 with a specific capacity limit of 500 mAh g -1）. These excellent performances are derived from the synergy of the following advantageous factors： （1） the hierarchically self-standing and binder-free structure of MCNFs could ensure the high diffusion flux of Li＋ and O2 as well as avoid clogging of the discharge product, bulk Li202; （2） the well dispersed M02C nanoparticles not only afford rich active sites, but also facilitate the electronic transfer for catalysis.展开更多
基金supported by the National Natural Science Foundation of China(Nos.21903007,22072006,and 22275022)Young Thousand Talents Program(No.110532103)+2 种基金Beijing Normal University Startup funding(No.312232102)Beijing Municipal Science&Technology Commission(No.Z191100000819002)the Fundamental Research Funds for the Central Universities(No.310421109).
文摘Tattoo electronics has attracted intensive interest in recent years due to its comfortable wearing and imperceivable sensing,and has been broadly applied in wearable healthcare and human-machine interface.However,the tattoo electrodes are mostly composed of metal films and conductive polymers.Two-dimensional(2D)materials,which are superior in conductivity and stability,are barely studied for electronic tattoos.Herein,we reported a novel electronic tattoo based on large-area Mo_(2)C film grown by chemical vapor deposition(CVD),and applied it to accurately and imperceivably acquire on-body electrophysiological signals and interface with robotics.High-quality Mo_(2)C film was obtained via optimizing the distribution of gas flow during CVD growth.According to the finite element simulation(FES),bottom surface of Cu foil covers more stable gas flow than the top surface,thus leading to more uniform Mo_(2)C film.The resulting Mo_(2)C film was transferred onto tattoo paper,showing a total thickness of~3μm,sheet resistance of 60-150Ω/sq,and skin-electrode impedance of~5×10^(5)Ω.Such thin Mo_(2)C electronic tattoo(MCET in short)can form conformal contact with skin and accurately record electrophysiological signals,including electromyography(EMG),electrocardiogram(ECG),and electrooculogram(EOG).These body signals collected by MCET can not only reflect the health status but also be transformed to control the robotics for human-machine interface.
基金supported by the National Key Research and Development Program of China(2017YFA0206704 and 2016YFB0100103)the National Basic Research Program of China(2014CB932300)+3 种基金Strategic Priority Research Program of the Chinese Academy of Sciences(XDA09010404)Technology and Industry for National Defence of China(JCKY2016130B010)the National Natural Science Foundation of China(51771177,21422108,51472209,and 51472232)Jilin Province Science and Technology Development Program(20160101289JC)
文摘A facile synthesis of the hierarchically porous cathode with Mo2C nanoparticles through the electrospinning technique and heat treatment is proposed. The carbonization temperature of the precursors is the key factor for the formation of M02C nanoparticles on the carbon nanofibers （MCNFs）. Compared with the Mo2N nanoparticles embedded into N-doped carbon nanofibers film （MNNFs） and N-doped carbon nanofibers film （NFs）, the battery with MCNFs cathode is capable of operation with a high-capacity （10,509 mAhg-1 at 100 mAg-l）, a much reduced discharge-charge voltage gap, and a long-term life （124 cycles at 200 mA g-1 with a specific capacity limit of 500 mAh g -1）. These excellent performances are derived from the synergy of the following advantageous factors： （1） the hierarchically self-standing and binder-free structure of MCNFs could ensure the high diffusion flux of Li＋ and O2 as well as avoid clogging of the discharge product, bulk Li202; （2） the well dispersed M02C nanoparticles not only afford rich active sites, but also facilitate the electronic transfer for catalysis.
