Flexible electronic sensors composed of flexible film and conductive materials play an increasingly important role in wearable and internet information transmission.It has received more and more attention and made som...Flexible electronic sensors composed of flexible film and conductive materials play an increasingly important role in wearable and internet information transmission.It has received more and more attention and made some progress over the decades.However,it is still a great challenge to prepare biocompatible and highly transparent conductive films.Egg white is a pure natural protein-rich material.Hydroxypropylmethyl cellulose has a good compatibility and high transparency,which is an ideal material for flexible sensors.Here,we overcome the problem of poor mechanical flexibility and electrical conductivity of protein,and develop a high transparency and good flexibility hydroxypropylmethyl cellulose/egg white protein composite membrane-based triboelectric nanogenerator('X'-TENG).The experimental results show that the flexible pressure sensor based on'X'-TENG has a high sensitivity,fast response speed,and low detection limit.It can even be used as a touch/pressure sensing artificial electronic skin.It can also be made into an intelligent waffle keyboard for recording and tracking users of the keyboard.Our strategy may provide a new way to easily build flexible electronic sensors and move toward practical applications.展开更多
Due to the push for carbon neutrality in various human activities,the development of methods for producing electricity without relying on chemical reaction processes or heat sources has become highly significant.Also,...Due to the push for carbon neutrality in various human activities,the development of methods for producing electricity without relying on chemical reaction processes or heat sources has become highly significant.Also,the challenge lies in achieving microwatt-scale outputs due to the inherent conductivity of the materials and diverting electric currents.To address this challenge,our research has concentrated on utilizing nonconductive mediums for water-based low-cost microfibrous ceramic wools in conjunction with a NaCl aqueous solution for power generation.The main source of electricity originates from the directed movement of water molecules and surface ions through densely packed microfibrous ceramic wools due to the effect of dynamic electric double layer.This occurrence bears resemblance to the natural water transpiration in plants,thereby presenting a fresh and straightforward approach for producing electricity in an ecofriendly manner.The generator module demonstrated in this study,measuring 12×6 cm^(2),exhibited a noteworthy open-circuit voltage of 0.35 V,coupled with a short-circuit current of 0.51 mA.Such low-cost ceramic wools are suitable for ubiquitous,permanent energy sources and hold potential for use as self-powered sensors and systems,eliminating the requirement for external energy sources such as sunlight or heat.展开更多
Plant photosynthetic capacity directly determines crop yield. Light quality regulates photosynthetic capacity. This review discusses plant responses to far-red light from the phenotypic to the molecular level, focusin...Plant photosynthetic capacity directly determines crop yield. Light quality regulates photosynthetic capacity. This review discusses plant responses to far-red light from the phenotypic to the molecular level, focusing specifically on the improvement of photosynthetic capacity by adjustment of photosynthetic electron transport and the path of light energy. Far-red light can also regulate leaf angle and increase plant height and leaf area, via expression of associated genes, to capture more light energy.Thus, far-red light regulates plant morphology and photosynthetic capacity. Identifying the mechanism of this regulation may lead to increased crop yields.展开更多
Assessing canopy nitrogen content(CNC) and canopy carbon content(CCC) of maize by hyperspectral remote sensing data permits estimating cropland productivity, protecting farmland ecology, and investigating the nitrogen...Assessing canopy nitrogen content(CNC) and canopy carbon content(CCC) of maize by hyperspectral remote sensing data permits estimating cropland productivity, protecting farmland ecology, and investigating the nitrogen and carbon cycles in the atmosphere. This study aimed to assess maize CNC and CCC using canopy hyperspectral information and uninformative variable elimination(UVE). Vegetation indices(VIs) and wavelet functions were adopted for estimating CNC and CCC under varying water and nitrogen regimes. Linear, nonlinear, and partial least squares(PLS) regression models were fitted to VIs and wavelet functions to estimate CNC and CCC, and were evaluated for their prediction accuracy.UVE was used to eliminate uninformative variables, improve the prediction accuracy of the models, and simplify the PLS regression models(UVE-PLS). For estimating CNC and CCC, the normalized difference vegetation index(NDVI, based on red edge and NIR wavebands) yielded the highest correlation coefficients(r > 0.88). PLS regression models showed the lowest root mean square error(RMSE) among all models. However, PLS regression models required nine VIs and four wavelet functions, increasing their complexity. UVE was used to retain valid spectral parameters and optimize the PLS regression models.UVE-PLS regression models improved validation accuracy and resulted in more accurate CNC and CCC than the PLS regression models. Thus, canopy spectral reflectance integrated with UVE-PLS can accurately reflect maize leaf nitrogen and carbon status.展开更多
[Objectives]To improve the yield of flavonoids from Dendrobium nobile Lindl.[Methods]On the basis of four single-factor experiments of solid/liquid ratio,extraction temperature,extraction time and ethanol volume fract...[Objectives]To improve the yield of flavonoids from Dendrobium nobile Lindl.[Methods]On the basis of four single-factor experiments of solid/liquid ratio,extraction temperature,extraction time and ethanol volume fraction,the ultrasonic-assisted extraction process of total flavonoids from D.nobile Lindl.was optimized using quadratic general rotary unitized design,and the in-vitro anti-oxidant activity of the flavonoids extracted was evaluated preliminarily.[Results]The optimized extraction process for flavonoids in D.nobile Lindl.was as follows:extraction time 10 min,solid/liquid ratio 1∶15(g∶mL),extraction temperature 75℃and ethanol volume fraction 90%.According to the revised optimal process,6 repeated experiments were carried out,and the average yield of flavonoids was(0.5515±0.0004)mg/g,consistent with the predicted value of the model.The results of anti-oxidation experiment show that the flavonoids extracted from D.nobile Lindl.have better scavenging effect on ABTS and DPPH free radicals,and the scavenging activity is proportional to the mass concentration of the extract.[Conclusions]The optimized extraction process for flavonoids from D.nobile Lindl.is reasonable and feasible,and the flavonoids in D.nobile Lindl.have strong antioxidant activity.展开更多
A narrow resonance bandwidth of an energy harvesters limits its response to the wide frequency spectrum in ambient environ-ments.This work proposes an addition of a nonlinear restoring force applied to a triboelectric...A narrow resonance bandwidth of an energy harvesters limits its response to the wide frequency spectrum in ambient environ-ments.This work proposes an addition of a nonlinear restoring force applied to a triboelectric nanogenerator(TENG)to tune and broaden the resonance bandwidth.This restoring force is applied by permanent magnets at both sides of the slider and two external magnets.The noncontact strategy is adopted between the slider and the grating electrodes to avoid the wear of electrodes and energy loss caused by friction.The results show that compared with the linear system,the nonlinear noncontact TENG(NN-TENG)can increase the peak current from 6.3μA to 7.89μA,with an increment of about 25%,increase the peak power from 650μW to 977μW,increasing by about 50%,and increase the bandwidth from 0.5 Hz to 7.75 Hz,increasing by about1400%.This work may enable a new strategy to boost the bandwidth and output power of TENG through nonlinear oscillators.展开更多
The control of ion transport by responding to stimulus is a necessary condition for the existence of life.Bioinspired iontronics could enable anomalous ion dynamics in the nano-confined spaces,creating many efficient ...The control of ion transport by responding to stimulus is a necessary condition for the existence of life.Bioinspired iontronics could enable anomalous ion dynamics in the nano-confined spaces,creating many efficient energy systems and neuromorphic in-sensor computing networks:Unlike tradi-tional electronics based on von Neumann computing architec-ture,the Boolean logic computing based on the iontronics could avoid complex wiring with higher energy efficiency and programmable neuromorphic logic.Here,a systematic summary on the state of art in bioinspired iontronics is pre-sented and the stimulus from chemical potentials,electric fields,light,heat,piezo and magnetic fields on ion dynamics are reviewed.Challenges and perspectives are also addressed in the aspects of iontronic integrated systems.It is believed that comprehensive investigations in bioinspired ionic control will accelerate the development on more efficient energy and information flow for the futuristic human-machine interface.展开更多
Triboelectric nanogenerators （TENG）, a unique technology for harvesting ambient mechanical energy based on triboelectric effect, have been proven to be a cost-effective, simple and robust approach for self-powered s...Triboelectric nanogenerators （TENG）, a unique technology for harvesting ambient mechanical energy based on triboelectric effect, have been proven to be a cost-effective, simple and robust approach for self-powered systems. Here, we demonstrate a rationally designed triple-cantilever based TENG for harvesting vibration energy. With the assistance of nanowire arrays fabricated onto the surfaces of beryllium-copper alloy foils, the newly designed TENG produces an open-circuit voltage up to 101 V and a short-circuit current of 55.7 ~tA with a peak power density of 252.3 mW/m2. The TENG was systematically investigated and demonstrated as a direct power source for instantaneously lighting up 40 commercial light-emitting diodes. For the first time, a TENG device has been designed for harvesting vibration energy, especially at low frequencies, opening its application as a new energy technologv.展开更多
The triboelectric nanogenerator （TENG）, based on the well-known triboelectric effect and electrostatic induction effect, has been proven to be a simple, cost effective approach for self-powered systems to convert am...The triboelectric nanogenerator （TENG）, based on the well-known triboelectric effect and electrostatic induction effect, has been proven to be a simple, cost effective approach for self-powered systems to convert ambient mechanical energy into electricity. We report a flexible and transparent paper-based triboelectric nanogenerator （PTENG） consisting of an indium tin oxide （ITO） film and a polyethylene terephthalate （PET） film as the triboelectric surfaces, which not only acts as an energy supply but also as a self-powered active sensor. It can harvest kinetic energy when the sheets of paper come into contact, bend or slide relative to one another by a combination of vertical contact-separation mode and lateral sliding mode. In addition, we also integrate grating-structured PTENGs into a book as a self-powered anti-theft sensor. The mechanical agitation during handling the book pages can be effectively converted into an electrical output to either drive a commercial electronic device or trigger a warning buzzer. Furthermore, different grating-structures on each page produce different numbers of output peaks by sliding relative to one another, which can accurately act as a page mark and record the number of pages turned. This work is a significant step forward in self-powered paper-based devices.展开更多
Over the past few years, the rapid development of tactile sensing technology has contributed significantly to the realization of intuitional touch control and intelligent human-machine interaction. Apart from physical...Over the past few years, the rapid development of tactile sensing technology has contributed significantly to the realization of intuitional touch control and intelligent human-machine interaction. Apart from physical touch or pressure sensing, proximity sensing as a complementary function can extend the detection mode of common single functional tactile sensors. In this work, we present a transparent, matrix-structure dual functional capacitive sensor which integrates the capability of proximity and pressure sensing in one device, and the excellent spatial resolution offered by the isolated response of capacitive pixels enables us to realize precise location identification of approaching objects and loaded pressure with fast response, high stability and high reversibility.展开更多
Untapped thermal energy,especially low-grade heat below 373 K from various sources,namely ambient,industries residual,and non-concentrated solar energy,is abundant and widely accessible.Despite that,there are huge con...Untapped thermal energy,especially low-grade heat below 373 K from various sources,namely ambient,industries residual,and non-concentrated solar energy,is abundant and widely accessible.Despite that,there are huge constraints to recycle this valuable low-grade heat using the existing technologies due to the variability of thermal energy output and the small temperature difference between the heat source and environment.Here,a thermal-mechanical-electrical energy conversion(TMEc)system based on the Curie effect and the soft-contact rotary triboelectric nanogenerator(TENG)is developed to recycle thermal energy in the mid-low temperature range.According to the phase transition mechanism between ferromagnetic and paramagnetic,disk-shaped ferromagnetic materials can realize stable rotation under external magnetic and thermal fields,thus activating the operation of TENGs and realizing the conversion of thermal energy and electrical energy.During the steady rotation process,an open-circuit voltage(VOC)of 173 V and a short-circuit current(ISC)of 1.32μA are measured.We finally obtained a maximum power of 4.45 mW in the actual working conditions,and it successfully charged different capacitors.This work provides a new method for mid-low temperature energy harvesting and thermal energy transformation and broadens the application of TENG in the field of thermal energy recovery.展开更多
Because of the coupling between semiconducting and piezoelectric properties in wurtzite materials, strain-induced piezo-charges can tune the charge transport across the interface or junction, which is referred to as t...Because of the coupling between semiconducting and piezoelectric properties in wurtzite materials, strain-induced piezo-charges can tune the charge transport across the interface or junction, which is referred to as the piezotronic effect. For devices whose dimension is much smaller than the mean free path of carriers （such as a single atomic layer of MoS2）, ballistic transport occurs. In this study, transport in the monolayer MoS2 piezotronic transistor is studied by presenting analytical solutions for two-dimensional （2D） MoS2. Furthermore, a numerical simulation for guiding future 2D piezotronic nanodevice design is presented.展开更多
Anodic oxidization （AO） is one of the most important methods available for fabricating mesoporous Al2O3 , which can be conducted at either high potential or low potential; however, the need for an external electrici...Anodic oxidization （AO） is one of the most important methods available for fabricating mesoporous Al2O3 , which can be conducted at either high potential or low potential; however, the need for an external electricity power source limits its applications. In this work, a novel self-powered electrochemical anodic oxidization （SPAO） system was introduced for preparing mesoporous Al2O3 , by using newly-invented triboelectric nanogenerator （TENG） arrays driven by wind power. Using the controllable voltage output of the TENG arrays, the SPAO system was shown to regulate the pore depth and pore size of the mesoporous Al2O3 . In contrast to traditional AO systems, this technique takes advantage of the high output voltage of TENG arrays without any additional energy costs. In addition, the SPAO system can be used for the preparation of other mesoporous materials.展开更多
Along with the unceasing growth of worldwide economic and the associated issues on resources,energy and environment,clean energy generating technologies that are based on recyclable materials,if possible,may become th...Along with the unceasing growth of worldwide economic and the associated issues on resources,energy and environment,clean energy generating technologies that are based on recyclable materials,if possible,may become the future trend of development.Here,we report the design of a cheap,lightweight,and recyclable single-electrode triboelectric nanogenerator(TENG)that utilizes waste paper as the triboelectric material.Under the current strategy,we successfully developed green energy machines without vastly increasing the mining of various critical minerals around the world.The as-designed TENG could not only collect and convert mechanical energy into electricity with sound efficiency,but also has the merit for continuous reuse and quick construction.The maximum output power density is as high as 171 mW·m^(-2) at a resistance of 130 MQ and could be integrated into a book for monitoring reading actions,thus providing a new approach to the low-cost,green and sustainable self-powered electronic systems.展开更多
基金financially supported by the National Key R&D Project from Ministry of Science and Technology,China(2016YFA0202702,2016YFA0202701)the Key Research Program of Frontier Sciences,CAS(ZDBS-LY-DQC025)
文摘Flexible electronic sensors composed of flexible film and conductive materials play an increasingly important role in wearable and internet information transmission.It has received more and more attention and made some progress over the decades.However,it is still a great challenge to prepare biocompatible and highly transparent conductive films.Egg white is a pure natural protein-rich material.Hydroxypropylmethyl cellulose has a good compatibility and high transparency,which is an ideal material for flexible sensors.Here,we overcome the problem of poor mechanical flexibility and electrical conductivity of protein,and develop a high transparency and good flexibility hydroxypropylmethyl cellulose/egg white protein composite membrane-based triboelectric nanogenerator('X'-TENG).The experimental results show that the flexible pressure sensor based on'X'-TENG has a high sensitivity,fast response speed,and low detection limit.It can even be used as a touch/pressure sensing artificial electronic skin.It can also be made into an intelligent waffle keyboard for recording and tracking users of the keyboard.Our strategy may provide a new way to easily build flexible electronic sensors and move toward practical applications.
基金supported by JSPS Kakenhi program(program number 16H06364)and JST CRESTThe authors extend their appreciation to the Deputyship for Research and Innovation,“Ministry of Education”in Saudi Arabia for funding this research(IFKSUOR3-615-5)O.M.also thank the support of Tomsk State University Development Programme(priority-2030)for this work.
文摘Due to the push for carbon neutrality in various human activities,the development of methods for producing electricity without relying on chemical reaction processes or heat sources has become highly significant.Also,the challenge lies in achieving microwatt-scale outputs due to the inherent conductivity of the materials and diverting electric currents.To address this challenge,our research has concentrated on utilizing nonconductive mediums for water-based low-cost microfibrous ceramic wools in conjunction with a NaCl aqueous solution for power generation.The main source of electricity originates from the directed movement of water molecules and surface ions through densely packed microfibrous ceramic wools due to the effect of dynamic electric double layer.This occurrence bears resemblance to the natural water transpiration in plants,thereby presenting a fresh and straightforward approach for producing electricity in an ecofriendly manner.The generator module demonstrated in this study,measuring 12×6 cm^(2),exhibited a noteworthy open-circuit voltage of 0.35 V,coupled with a short-circuit current of 0.51 mA.Such low-cost ceramic wools are suitable for ubiquitous,permanent energy sources and hold potential for use as self-powered sensors and systems,eliminating the requirement for external energy sources such as sunlight or heat.
基金supported by the National Natural Science Foundation of China(32071963)the International S&T Cooperation Projects of Sichuan Province(2020YFH0126)the China Agriculture Research System(CARS-04-PS19)。
文摘Plant photosynthetic capacity directly determines crop yield. Light quality regulates photosynthetic capacity. This review discusses plant responses to far-red light from the phenotypic to the molecular level, focusing specifically on the improvement of photosynthetic capacity by adjustment of photosynthetic electron transport and the path of light energy. Far-red light can also regulate leaf angle and increase plant height and leaf area, via expression of associated genes, to capture more light energy.Thus, far-red light regulates plant morphology and photosynthetic capacity. Identifying the mechanism of this regulation may lead to increased crop yields.
基金supported by the National Key Research and Development Program of China (2016YFD0300602)China Agricultural Research System (CARS-04-PS19)Chengdu Science and Technology Project (2020-YF09-00033-SN)。
文摘Assessing canopy nitrogen content(CNC) and canopy carbon content(CCC) of maize by hyperspectral remote sensing data permits estimating cropland productivity, protecting farmland ecology, and investigating the nitrogen and carbon cycles in the atmosphere. This study aimed to assess maize CNC and CCC using canopy hyperspectral information and uninformative variable elimination(UVE). Vegetation indices(VIs) and wavelet functions were adopted for estimating CNC and CCC under varying water and nitrogen regimes. Linear, nonlinear, and partial least squares(PLS) regression models were fitted to VIs and wavelet functions to estimate CNC and CCC, and were evaluated for their prediction accuracy.UVE was used to eliminate uninformative variables, improve the prediction accuracy of the models, and simplify the PLS regression models(UVE-PLS). For estimating CNC and CCC, the normalized difference vegetation index(NDVI, based on red edge and NIR wavebands) yielded the highest correlation coefficients(r > 0.88). PLS regression models showed the lowest root mean square error(RMSE) among all models. However, PLS regression models required nine VIs and four wavelet functions, increasing their complexity. UVE was used to retain valid spectral parameters and optimize the PLS regression models.UVE-PLS regression models improved validation accuracy and resulted in more accurate CNC and CCC than the PLS regression models. Thus, canopy spectral reflectance integrated with UVE-PLS can accurately reflect maize leaf nitrogen and carbon status.
基金Key Science and Technology Program of Science&Technology Department of Henan Province(172102310211,182102110166,192102310087,202102310478)Key Scientific and Technological Research Project for Colleges and Universities(18A180026,20B350006)+1 种基金Starting Foundation of Pingdingshan University for High-level Talents(PXY-BSQD-2018011,PXY-BSQD-2018010)Cultivation Fund of Pingdingshan University(PXY-PYJJ-2019007)。
文摘[Objectives]To improve the yield of flavonoids from Dendrobium nobile Lindl.[Methods]On the basis of four single-factor experiments of solid/liquid ratio,extraction temperature,extraction time and ethanol volume fraction,the ultrasonic-assisted extraction process of total flavonoids from D.nobile Lindl.was optimized using quadratic general rotary unitized design,and the in-vitro anti-oxidant activity of the flavonoids extracted was evaluated preliminarily.[Results]The optimized extraction process for flavonoids in D.nobile Lindl.was as follows:extraction time 10 min,solid/liquid ratio 1∶15(g∶mL),extraction temperature 75℃and ethanol volume fraction 90%.According to the revised optimal process,6 repeated experiments were carried out,and the average yield of flavonoids was(0.5515±0.0004)mg/g,consistent with the predicted value of the model.The results of anti-oxidation experiment show that the flavonoids extracted from D.nobile Lindl.have better scavenging effect on ABTS and DPPH free radicals,and the scavenging activity is proportional to the mass concentration of the extract.[Conclusions]The optimized extraction process for flavonoids from D.nobile Lindl.is reasonable and feasible,and the flavonoids in D.nobile Lindl.have strong antioxidant activity.
基金supported by HKSAR the Research Grants Council Early Career Scheme(Grant No.24206919)Guangdong Basic and Applied Basic Research Foundation(Project No.2020A1515111161)This work was supported in part by the Project of Hetao Shenzhen-Hong Kong Science and Technology Innovation Cooperation Zone(HZQB-KCZYB-2020083).
文摘A narrow resonance bandwidth of an energy harvesters limits its response to the wide frequency spectrum in ambient environ-ments.This work proposes an addition of a nonlinear restoring force applied to a triboelectric nanogenerator(TENG)to tune and broaden the resonance bandwidth.This restoring force is applied by permanent magnets at both sides of the slider and two external magnets.The noncontact strategy is adopted between the slider and the grating electrodes to avoid the wear of electrodes and energy loss caused by friction.The results show that compared with the linear system,the nonlinear noncontact TENG(NN-TENG)can increase the peak current from 6.3μA to 7.89μA,with an increment of about 25%,increase the peak power from 650μW to 977μW,increasing by about 50%,and increase the bandwidth from 0.5 Hz to 7.75 Hz,increasing by about1400%.This work may enable a new strategy to boost the bandwidth and output power of TENG through nonlinear oscillators.
基金supported by the Beijing Natural Science Foundation[Grant No.IS23040].
文摘The control of ion transport by responding to stimulus is a necessary condition for the existence of life.Bioinspired iontronics could enable anomalous ion dynamics in the nano-confined spaces,creating many efficient energy systems and neuromorphic in-sensor computing networks:Unlike tradi-tional electronics based on von Neumann computing architec-ture,the Boolean logic computing based on the iontronics could avoid complex wiring with higher energy efficiency and programmable neuromorphic logic.Here,a systematic summary on the state of art in bioinspired iontronics is pre-sented and the stimulus from chemical potentials,electric fields,light,heat,piezo and magnetic fields on ion dynamics are reviewed.Challenges and perspectives are also addressed in the aspects of iontronic integrated systems.It is believed that comprehensive investigations in bioinspired ionic control will accelerate the development on more efficient energy and information flow for the futuristic human-machine interface.
基金This research was supported by the U.S. Department of Energy, Office of Basic Energy Sciences （Award No. DE-FG02-07ER46394）, National Science Foundation （NSF） （No. 0946418）, and the Knowledge Innovation Program of the Chinese Academy of Sciences （Grant No. KJCX2-YW-M13）. Patents have been filed based on the research results presented in this manuscript.
文摘Triboelectric nanogenerators （TENG）, a unique technology for harvesting ambient mechanical energy based on triboelectric effect, have been proven to be a cost-effective, simple and robust approach for self-powered systems. Here, we demonstrate a rationally designed triple-cantilever based TENG for harvesting vibration energy. With the assistance of nanowire arrays fabricated onto the surfaces of beryllium-copper alloy foils, the newly designed TENG produces an open-circuit voltage up to 101 V and a short-circuit current of 55.7 ~tA with a peak power density of 252.3 mW/m2. The TENG was systematically investigated and demonstrated as a direct power source for instantaneously lighting up 40 commercial light-emitting diodes. For the first time, a TENG device has been designed for harvesting vibration energy, especially at low frequencies, opening its application as a new energy technologv.
文摘The triboelectric nanogenerator （TENG）, based on the well-known triboelectric effect and electrostatic induction effect, has been proven to be a simple, cost effective approach for self-powered systems to convert ambient mechanical energy into electricity. We report a flexible and transparent paper-based triboelectric nanogenerator （PTENG） consisting of an indium tin oxide （ITO） film and a polyethylene terephthalate （PET） film as the triboelectric surfaces, which not only acts as an energy supply but also as a self-powered active sensor. It can harvest kinetic energy when the sheets of paper come into contact, bend or slide relative to one another by a combination of vertical contact-separation mode and lateral sliding mode. In addition, we also integrate grating-structured PTENGs into a book as a self-powered anti-theft sensor. The mechanical agitation during handling the book pages can be effectively converted into an electrical output to either drive a commercial electronic device or trigger a warning buzzer. Furthermore, different grating-structures on each page produce different numbers of output peaks by sliding relative to one another, which can accurately act as a page mark and record the number of pages turned. This work is a significant step forward in self-powered paper-based devices.
基金This work was supported by the National Natural Science Foundation of China （No. 61204001）, and the Fundamental Research Funds for the Central Universities of China （No. 2014QN013）. We also thank the Center for Nanoscale Characterization ＆ Devices （CNCD）, WNLO of HUST for the use of facilities in support of this work.
文摘Over the past few years, the rapid development of tactile sensing technology has contributed significantly to the realization of intuitional touch control and intelligent human-machine interaction. Apart from physical touch or pressure sensing, proximity sensing as a complementary function can extend the detection mode of common single functional tactile sensors. In this work, we present a transparent, matrix-structure dual functional capacitive sensor which integrates the capability of proximity and pressure sensing in one device, and the excellent spatial resolution offered by the isolated response of capacitive pixels enables us to realize precise location identification of approaching objects and loaded pressure with fast response, high stability and high reversibility.
基金supported by the National Natural Science Foundation of China(No.61503051).
文摘Untapped thermal energy,especially low-grade heat below 373 K from various sources,namely ambient,industries residual,and non-concentrated solar energy,is abundant and widely accessible.Despite that,there are huge constraints to recycle this valuable low-grade heat using the existing technologies due to the variability of thermal energy output and the small temperature difference between the heat source and environment.Here,a thermal-mechanical-electrical energy conversion(TMEc)system based on the Curie effect and the soft-contact rotary triboelectric nanogenerator(TENG)is developed to recycle thermal energy in the mid-low temperature range.According to the phase transition mechanism between ferromagnetic and paramagnetic,disk-shaped ferromagnetic materials can realize stable rotation under external magnetic and thermal fields,thus activating the operation of TENGs and realizing the conversion of thermal energy and electrical energy.During the steady rotation process,an open-circuit voltage(VOC)of 173 V and a short-circuit current(ISC)of 1.32μA are measured.We finally obtained a maximum power of 4.45 mW in the actual working conditions,and it successfully charged different capacitors.This work provides a new method for mid-low temperature energy harvesting and thermal energy transformation and broadens the application of TENG in the field of thermal energy recovery.
基金This work was supported by the ＂thousands talents＂ program for pioneer researcher and his innovation team, China, the National Natural Science Foundation of China （No. 51432005）, and Beijing Municipal Commission of Science and Technology （Nos. Z131100006013005 and Z131100006013004）.
文摘Because of the coupling between semiconducting and piezoelectric properties in wurtzite materials, strain-induced piezo-charges can tune the charge transport across the interface or junction, which is referred to as the piezotronic effect. For devices whose dimension is much smaller than the mean free path of carriers （such as a single atomic layer of MoS2）, ballistic transport occurs. In this study, transport in the monolayer MoS2 piezotronic transistor is studied by presenting analytical solutions for two-dimensional （2D） MoS2. Furthermore, a numerical simulation for guiding future 2D piezotronic nanodevice design is presented.
基金Acknowledgements We thank the financial support from the National Natural Science Foundation of China （NSFC） （Nos. 21173017, 51272011, and 21275102）, the Program for New Century Excellent Talents in University （No. NCET-12-0610）, the Science and Technology Research Projects from Education Ministry （No. 213002A）, National ＂Twelfth Five-Year＂ Plan for Science ＆ Technology Support （No. 2013BAK12B06）, the ＂thousands talents＂ program for pioneer researcher and his innovation team, China, National Natural Science Foundation of China （Nos. 51432005 and Y4YR011001）, Beijing Municipal Commission of Science and Technology （Nos. Z131100006013004 and Z131100006013005）.
文摘Anodic oxidization （AO） is one of the most important methods available for fabricating mesoporous Al2O3 , which can be conducted at either high potential or low potential; however, the need for an external electricity power source limits its applications. In this work, a novel self-powered electrochemical anodic oxidization （SPAO） system was introduced for preparing mesoporous Al2O3 , by using newly-invented triboelectric nanogenerator （TENG） arrays driven by wind power. Using the controllable voltage output of the TENG arrays, the SPAO system was shown to regulate the pore depth and pore size of the mesoporous Al2O3 . In contrast to traditional AO systems, this technique takes advantage of the high output voltage of TENG arrays without any additional energy costs. In addition, the SPAO system can be used for the preparation of other mesoporous materials.
基金support from the National key R and D Project from Minister of Science and Technology,China(Nos.2016YFA0202702 and 2016YFA0202701)the Key Research Program of Frontier Sciences,Chinese Academy of Sciences(CAS)(No.ZDBS-LY-DQC025).
文摘Along with the unceasing growth of worldwide economic and the associated issues on resources,energy and environment,clean energy generating technologies that are based on recyclable materials,if possible,may become the future trend of development.Here,we report the design of a cheap,lightweight,and recyclable single-electrode triboelectric nanogenerator(TENG)that utilizes waste paper as the triboelectric material.Under the current strategy,we successfully developed green energy machines without vastly increasing the mining of various critical minerals around the world.The as-designed TENG could not only collect and convert mechanical energy into electricity with sound efficiency,but also has the merit for continuous reuse and quick construction.The maximum output power density is as high as 171 mW·m^(-2) at a resistance of 130 MQ and could be integrated into a book for monitoring reading actions,thus providing a new approach to the low-cost,green and sustainable self-powered electronic systems.
