A typical high-e fficiency solar cell device needs the best lattice matching between different constituent layers to mitigate the open-circuit voltage loss. In the present work, the physical properties of CdS thin fil...A typical high-e fficiency solar cell device needs the best lattice matching between different constituent layers to mitigate the open-circuit voltage loss. In the present work, the physical properties of CdS thin films are investigated where films with 100 nm thickness were fabricated on the different types of substrates viz. soda–lime glass, indium-doped tin oxide(ITO)-and fl uorine-doped tin oxide(FTO)-coated glass substrates, and silicon wafer using electron beam evaporation. The X-ray diffraction patterns confirmed that deposited thin films showed cubic phase and had(111) as predominant orientation where the structural parameters were observed to be varied with nature of substrates. The ohmic behaviour of the CdS films was disclosed by current–voltage characteristics, whereas the scanning electron microscopy micrograph revealed the uniform deposition of the CdS films with the presence of round-shaped grains. The elemental analysis confirmed the CdS films deposition where the Cd/S weight percentage ratio was changed with nature of substrates. The direct energy band gap was observed in the 1.63–2.50 eV range for the films grown on different substrates. The investigated properties of thin CdS layers demonstrated that the selection of substrate(in terms of nature) during device fabrication plays a crucial role.展开更多
Aluminum-doped ZnO(AZO) thin films with thin film metallic glass of Zr(50)Cu(50) as buffer are prepared on glass substrates by the pulsed laser deposition. The influence of buffer thickness and substrate temperature o...Aluminum-doped ZnO(AZO) thin films with thin film metallic glass of Zr(50)Cu(50) as buffer are prepared on glass substrates by the pulsed laser deposition. The influence of buffer thickness and substrate temperature on structural, optical, and electrical properties of AZO thin film are investigated. Increasing the thickness of buffer layer and substrate temperature can both promote the transformation of AZO from amorphous to crystalline structure, while they show(100)and(002) unique preferential orientations, respectively. After inserting Zr(50)Cu(50) layer between the glass substrate and AZO film, the sheet resistance and visible transmittance decrease, but the infrared transmittance increases. With substrate temperature increasing from 25℃ to 520℃, the sheet resistance of AZO(100 nm)/Zr(50)Cu(50)(4 nm) film first increases and then decreases, and the infrared transmittance is improved. The AZO(100 nm)/Zr(50)Cu(50)(4 nm) film deposited at a substrate temperature of 360℃ exhibits a low sheet resistance of 26.7 ?/, high transmittance of 82.1% in the visible light region, 81.6% in near-infrared region, and low surface roughness of 0.85 nm, which are useful properties for their potential applications in tandem solar cell and infrared technology.展开更多
Thin films of ZnxCd1-xS have been prepared by electron beam evaporation of a mixture of ZnS & CdS powders. The films are deposited onto sodalime glass slides under similar conditions.The composition of the films i...Thin films of ZnxCd1-xS have been prepared by electron beam evaporation of a mixture of ZnS & CdS powders. The films are deposited onto sodalime glass slides under similar conditions.The composition of the films is varied from CdS to ZnS (x=0 to 1). The films show a regular change in color from toner red to orange yellow as Zn concentration increases to maximum.These films are characterized for their optical, electricaI and structural properties. The bandgap value of ZnxCd1-xS films is found to vary linearIy from 2.20 eV to 3.44 eV with change in the x value from 0 to 1. The resistivity of these films is in the range of 171.0 Ωcm to 5.5× 106Ωcm for x=0~0.6. All the samples show cubic structure after annealing in air at 250℃ for 40 min.The lattice constant ao varies from 0.5884 nm to 0.54109 nm linearly.展开更多
The transparent conductive Mg-Ga co-doped Zn O(MGZO) films were prepared by radio-frequency(RF) magnetron sputtering. The influence of substrate temperature on the structural and optoelectrical properties of the films...The transparent conductive Mg-Ga co-doped Zn O(MGZO) films were prepared by radio-frequency(RF) magnetron sputtering. The influence of substrate temperature on the structural and optoelectrical properties of the films is studied. The results show that all the films possess a preferential orientation along the(002) plane. With the increase of substrate temperature, the structure and optoelectrical properties of the films can be changed. When substrate temperature is 300 ℃, the deposited film exhibits the best crystalline quality and optoelectrical properties, with the minimum micro strain of 1.09×10^(-3), the highest average visible transmittance of 82.42%, the lowest resistivity of 1.62×10^(-3) Ω·cm and the highest figure of merit of 3.18×10~3 Ω^(-1)·cm^(-1). The optical bandgaps of the films are observed to be in the range of 3.342—3.545 eV. The refractive index dispersion curves obey the Sellmeier's dispersion model.展开更多
Here,we report a facile method to produce pure silver nanowires(Ag NWs)with high yield.A highly conductive dispersant was used to ensure uniform dispersion of the Ag NWs.Without any posttreatment,the Ag NW networks,de...Here,we report a facile method to produce pure silver nanowires(Ag NWs)with high yield.A highly conductive dispersant was used to ensure uniform dispersion of the Ag NWs.Without any posttreatment,the Ag NW networks,deposited on flexible substrates,showed excellent optoelectrical performance owing to minimal junction resistance between the Ag NWs.To explore their potential in flexible optoelectronic devices,a transparent film heater was constructed based on the present Ag NW networks.The heater could achieve rapid response at low input voltage and reach a relatively high temperature in a short response time.Since this high-quality Ag NW film exhibits relatively low production costs and fast production time,it may have value for future electronic industry applications.展开更多
The controlled preparation of hexagonal tungsten trioxide(h-WO_(3))nanostructures was achieved by adjusting the pH of the precursor solution.The effect of the pH on the morphology,elemental composition,and photocataly...The controlled preparation of hexagonal tungsten trioxide(h-WO_(3))nanostructures was achieved by adjusting the pH of the precursor solution.The effect of the pH on the morphology,elemental composition,and photocatalytic performance of the samples was characterized via X-ray diffraction(XRD),scanning electron microscopy,energy dispersive X-ray spectroscopy,and Raman spectroscopy.Ultraviolet-visible(UV-Vis)spectra were used to evaluate the absorbance and the photocatalytic performance of methylene blue.Photoluminescence(PL),electrochemical impedance spectroscopy,photocurrent response and Brunauer-Emmett-Teller(BET)were used to study the optical properties,electrical performance,and specific surface area of the WO_(3)-nanostructures,respectively.The results indicate that the WO_(3) nanorods prepared at pH=1.0 exhibit the highest photocatalytic performance(87.4%in 1 h),whereas the WO_(3) nanoblocks prepared at p H=3.0 show the lowest.The photocatalytic performance of the one dimensional(1 D)-nanorods can be attributed to their high specific surface area and charge transfer ability.The h-WO_(3) nanostructures were synthesized via a simple method and without a capping agent.They show an excellent photocatalytic performance,which is promising for their application in environment purification.展开更多
Photoexcitation of a neutral soliton will create a polaron and a charged soliton. According to a tight-binding model and a nonadiabatic method, we investigate the dynamical process of these two photogenerated charge c...Photoexcitation of a neutral soliton will create a polaron and a charged soliton. According to a tight-binding model and a nonadiabatic method, we investigate the dynamical process of these two photogenerated charge carriers in an external electric field. It is found that the polaron and the soliton can pass through each other, which excludes the possibility of carrier recombination that usually occurs in existing organic solar cells. The results indicate a more efficient way to realize the optoelectric conversion by photoexciting polymer materials with soliton defects. On the other hand, it is found that solitons take on greater stability than polarons during collision.展开更多
Since the gas infrared absorption spectrum source intensity of several in a thousand, it is even less linewidth is only several nanometers occupying the than the noise of light source. The signal of gas absorption is ...Since the gas infrared absorption spectrum source intensity of several in a thousand, it is even less linewidth is only several nanometers occupying the than the noise of light source. The signal of gas absorption is submerged in the noise, so it is impossible to measure the concentration of gas with spectrum absorption directly. According to the principle and parameters of difference absorption system of CH4 gas, a detection circuit consisted of the lock-in amplifier is designed. The experiment results indicated that the detection circuit can satisfy the demand of the whole system, and the limit concentration is 150×10^-6.展开更多
Mimicking and extending biological sensory memory processing functions and systems—that play significant roles in enhancing interconnections of the human-physical world—are highly preferable for the Internet of Thin...Mimicking and extending biological sensory memory processing functions and systems—that play significant roles in enhancing interconnections of the human-physical world—are highly preferable for the Internet of Things.However,conventional artificial sensory systems usually consisted of separated modules or relied on perception-memory-processing devices with applications in a limited domain.Here,we propose a self-rectifying multifunctional synapse based on a unique PN optoelectrical memristor interface,achieving an augmented artificial visual system and multifunctional interconnected ports.The synapse realizes in-sensor motion perception and non-contact control beyond perception-memory-processing functions.The self-rectifying device can self-suppress the sneak current in cross-arrays,enabling large-scale and high-density integration.Further integrating synapse with quantum dot light-emitting diodes(QLEDs)evolves more powerful functions like hardware noise filtering and perception-memory-processing-displaying smart systems.展开更多
Imaging offers a fast and accessible means for spatial characterization of halide perovskite photovoltaic materials,yet extracting optoelectrical properties—such as power conversion efficiency(PCE)—remains challengi...Imaging offers a fast and accessible means for spatial characterization of halide perovskite photovoltaic materials,yet extracting optoelectrical properties—such as power conversion efficiency(PCE)—remains challenging.This study presents a deep learning methodology that correlates optical reflective images of perovskite solar cells with their PCE by focusing on image differences rather than absolute visual features.The approach predicts relative changes in PCE by comparing images of the same device in different states(e.g.,before and after encapsulation)or against a reference image.This comparative technique significantly outperforms traditional methods that attempt to directly infer PCE from a single image.Furthermore,it demonstrates high effectiveness in low-data regimes,using only 115 samples.By leveraging convolutional neural networks(CNNs)trained on small datasets,the method offers an adaptable and scalable solution for device characterization.Overall,the comparative approach enhances the accuracy and applicability of machine vision in perovskite solar cell analysis.展开更多
Exploring materials with multiple properties who can endow a simple device with integrated functionalities has attracted enormous attention in the microelectronic field. One reason is the imperious demand for processo...Exploring materials with multiple properties who can endow a simple device with integrated functionalities has attracted enormous attention in the microelectronic field. One reason is the imperious demand for processors with continuously higher performance and totally new architecture. Combining ferroelectric with semiconducting properties is a promising solution. Here, we show that logic, in-memory computing, and optoelectrical logic and non-volatile computing functionalities can be integrated into a single transistor with ferroelectric semiconducting α-In2Se3 as the channel. Two-input AND, OR, and nonvolatile NOR and NAND logic operations with current on/off ratios reaching up to five orders, good endurance(1000 operation cycles), and fast operating speed(10μs) are realized. In addition, optoelectrical OR logic and non-volatile implication(IMP) operations, as well as ternary-input optoelectrical logic and inmemory computing functions are achieved by introducing light as an additional input signal. Our work highlights the potential of integrating complex logic functions and new-type computing into a simple device based on emerging ferroelectric semiconductors.展开更多
In the path toward the realization of carbon nanotube(CNT)-driven electronics and sensors,the ability to precisely position CNTs at well-defined locations remains a significant roadblock.Highly complex CNT-based botto...In the path toward the realization of carbon nanotube(CNT)-driven electronics and sensors,the ability to precisely position CNTs at well-defined locations remains a significant roadblock.Highly complex CNT-based bottom–up structures can be synthesized if there is a method to accurately trap and place these nanotubes.In this study,we demonstrate that the rapid electrokinetic patterning(REP)technique can accomplish these tasks.By using laser-induced alternating current(AC)electrothermal flow and particle–electrode forces,REP can collect and maneuver a wide range of vertically aligned multiwalled CNTs(from a single nanotube to over 100 nanotubes)on an electrode surface.In addition,these trapped nanotubes can be electrophoretically deposited at any desired location onto the electrode surface.Apart from active control of the position of these deposited nanotubes,the number of CNTs in a REP trap can also be dynamically tuned by changing the AC frequency or by adjusting the concentration of the dispersed nanotubes.On the basis of a calculation of the stiffness of the REP trap,we found an upper limit of the manipulation speed,beyond which CNTs fall out of the REP trap.This peak manipulation speed is found to be dependent on the electrothermal flow velocity,which can be varied by changing the strength of the AC electric field.展开更多
Transition metal dichalcogenides(TMDCs)have suitable and adjustable band gaps,high carrier mobility and yield.Layered TMDCs have attracted great attention due to the structure diversity,stable existence in normal temp...Transition metal dichalcogenides(TMDCs)have suitable and adjustable band gaps,high carrier mobility and yield.Layered TMDCs have attracted great attention due to the structure diversity,stable existence in normal temperature environment and the band gap corresponding to wavelength between infrared and visible region.The ultra-thin,flat,almost defect-free surface,excellent mechanical flexibility and chemical stability provide convenient conditions for the construction of different types of TMDCs heterojunctions.The optoelectric properties of heterojunctions based on TMDCs materials are summarized in this review.Special electronic band structures of TMDCs heterojunctions lead to excellent optoelectric properties.The emitter,p-n diodes,photodetectors and photosensitive devices based on TMDCs heterojunction materials show excellent performance.These devices provide a prototype for the design and development of future high-performance optoelectric devices.展开更多
文摘A typical high-e fficiency solar cell device needs the best lattice matching between different constituent layers to mitigate the open-circuit voltage loss. In the present work, the physical properties of CdS thin films are investigated where films with 100 nm thickness were fabricated on the different types of substrates viz. soda–lime glass, indium-doped tin oxide(ITO)-and fl uorine-doped tin oxide(FTO)-coated glass substrates, and silicon wafer using electron beam evaporation. The X-ray diffraction patterns confirmed that deposited thin films showed cubic phase and had(111) as predominant orientation where the structural parameters were observed to be varied with nature of substrates. The ohmic behaviour of the CdS films was disclosed by current–voltage characteristics, whereas the scanning electron microscopy micrograph revealed the uniform deposition of the CdS films with the presence of round-shaped grains. The elemental analysis confirmed the CdS films deposition where the Cd/S weight percentage ratio was changed with nature of substrates. The direct energy band gap was observed in the 1.63–2.50 eV range for the films grown on different substrates. The investigated properties of thin CdS layers demonstrated that the selection of substrate(in terms of nature) during device fabrication plays a crucial role.
基金Project supported by the National Natural Science Foundation of China(Grant No.51571085)the Key Science and Technology Program of Henan Province,China(Grant No.19212210210)+1 种基金the Foundation of Henan Educational Committee,China(Grant No.13B430019)the Henan Postdoctoral Science Foundation,China。
文摘Aluminum-doped ZnO(AZO) thin films with thin film metallic glass of Zr(50)Cu(50) as buffer are prepared on glass substrates by the pulsed laser deposition. The influence of buffer thickness and substrate temperature on structural, optical, and electrical properties of AZO thin film are investigated. Increasing the thickness of buffer layer and substrate temperature can both promote the transformation of AZO from amorphous to crystalline structure, while they show(100)and(002) unique preferential orientations, respectively. After inserting Zr(50)Cu(50) layer between the glass substrate and AZO film, the sheet resistance and visible transmittance decrease, but the infrared transmittance increases. With substrate temperature increasing from 25℃ to 520℃, the sheet resistance of AZO(100 nm)/Zr(50)Cu(50)(4 nm) film first increases and then decreases, and the infrared transmittance is improved. The AZO(100 nm)/Zr(50)Cu(50)(4 nm) film deposited at a substrate temperature of 360℃ exhibits a low sheet resistance of 26.7 ?/, high transmittance of 82.1% in the visible light region, 81.6% in near-infrared region, and low surface roughness of 0.85 nm, which are useful properties for their potential applications in tandem solar cell and infrared technology.
文摘Thin films of ZnxCd1-xS have been prepared by electron beam evaporation of a mixture of ZnS & CdS powders. The films are deposited onto sodalime glass slides under similar conditions.The composition of the films is varied from CdS to ZnS (x=0 to 1). The films show a regular change in color from toner red to orange yellow as Zn concentration increases to maximum.These films are characterized for their optical, electricaI and structural properties. The bandgap value of ZnxCd1-xS films is found to vary linearIy from 2.20 eV to 3.44 eV with change in the x value from 0 to 1. The resistivity of these films is in the range of 171.0 Ωcm to 5.5× 106Ωcm for x=0~0.6. All the samples show cubic structure after annealing in air at 250℃ for 40 min.The lattice constant ao varies from 0.5884 nm to 0.54109 nm linearly.
基金supported by the National Natural Science Foundation of China(No.11504436)the Fundamental Research Funds for the Central Universities(Nos.CZP17002 and CZW14019)
文摘The transparent conductive Mg-Ga co-doped Zn O(MGZO) films were prepared by radio-frequency(RF) magnetron sputtering. The influence of substrate temperature on the structural and optoelectrical properties of the films is studied. The results show that all the films possess a preferential orientation along the(002) plane. With the increase of substrate temperature, the structure and optoelectrical properties of the films can be changed. When substrate temperature is 300 ℃, the deposited film exhibits the best crystalline quality and optoelectrical properties, with the minimum micro strain of 1.09×10^(-3), the highest average visible transmittance of 82.42%, the lowest resistivity of 1.62×10^(-3) Ω·cm and the highest figure of merit of 3.18×10~3 Ω^(-1)·cm^(-1). The optical bandgaps of the films are observed to be in the range of 3.342—3.545 eV. The refractive index dispersion curves obey the Sellmeier's dispersion model.
基金financial support from the National Natural Science Foundation of China(grant No.51471180)Science and Technology Program of Shenyang(grant No.F16-205-1-18)。
文摘Here,we report a facile method to produce pure silver nanowires(Ag NWs)with high yield.A highly conductive dispersant was used to ensure uniform dispersion of the Ag NWs.Without any posttreatment,the Ag NW networks,deposited on flexible substrates,showed excellent optoelectrical performance owing to minimal junction resistance between the Ag NWs.To explore their potential in flexible optoelectronic devices,a transparent film heater was constructed based on the present Ag NW networks.The heater could achieve rapid response at low input voltage and reach a relatively high temperature in a short response time.Since this high-quality Ag NW film exhibits relatively low production costs and fast production time,it may have value for future electronic industry applications.
基金the National Key R&D Program of China(No.2018YFC1901700)the National Natural Science Foundation of China(No.No51702008)。
文摘The controlled preparation of hexagonal tungsten trioxide(h-WO_(3))nanostructures was achieved by adjusting the pH of the precursor solution.The effect of the pH on the morphology,elemental composition,and photocatalytic performance of the samples was characterized via X-ray diffraction(XRD),scanning electron microscopy,energy dispersive X-ray spectroscopy,and Raman spectroscopy.Ultraviolet-visible(UV-Vis)spectra were used to evaluate the absorbance and the photocatalytic performance of methylene blue.Photoluminescence(PL),electrochemical impedance spectroscopy,photocurrent response and Brunauer-Emmett-Teller(BET)were used to study the optical properties,electrical performance,and specific surface area of the WO_(3)-nanostructures,respectively.The results indicate that the WO_(3) nanorods prepared at pH=1.0 exhibit the highest photocatalytic performance(87.4%in 1 h),whereas the WO_(3) nanoblocks prepared at p H=3.0 show the lowest.The photocatalytic performance of the one dimensional(1 D)-nanorods can be attributed to their high specific surface area and charge transfer ability.The h-WO_(3) nanostructures were synthesized via a simple method and without a capping agent.They show an excellent photocatalytic performance,which is promising for their application in environment purification.
基金supported by the Special Funds of the National Natural Foundation of China (Grant No. 11047148)the Jining University Research Program,China (Grant No. 2010QNKJ04)
文摘Photoexcitation of a neutral soliton will create a polaron and a charged soliton. According to a tight-binding model and a nonadiabatic method, we investigate the dynamical process of these two photogenerated charge carriers in an external electric field. It is found that the polaron and the soliton can pass through each other, which excludes the possibility of carrier recombination that usually occurs in existing organic solar cells. The results indicate a more efficient way to realize the optoelectric conversion by photoexciting polymer materials with soliton defects. On the other hand, it is found that solitons take on greater stability than polarons during collision.
基金Doctorate Foundation of Hebei Province(03547020D) Natural Science Foundation of Heilongjiang Province(F0312)
文摘Since the gas infrared absorption spectrum source intensity of several in a thousand, it is even less linewidth is only several nanometers occupying the than the noise of light source. The signal of gas absorption is submerged in the noise, so it is impossible to measure the concentration of gas with spectrum absorption directly. According to the principle and parameters of difference absorption system of CH4 gas, a detection circuit consisted of the lock-in amplifier is designed. The experiment results indicated that the detection circuit can satisfy the demand of the whole system, and the limit concentration is 150×10^-6.
基金supported by the National Natural Science Foundation of China(Grant No.62205063,62075043,62305254)Fujian Province Natural Science Foundation of China(Grant No.2023J05125,2022J05042)Fujian Normal University“Young Talent”Start-up Grant(Grant No.Y0720311K13)。
文摘Mimicking and extending biological sensory memory processing functions and systems—that play significant roles in enhancing interconnections of the human-physical world—are highly preferable for the Internet of Things.However,conventional artificial sensory systems usually consisted of separated modules or relied on perception-memory-processing devices with applications in a limited domain.Here,we propose a self-rectifying multifunctional synapse based on a unique PN optoelectrical memristor interface,achieving an augmented artificial visual system and multifunctional interconnected ports.The synapse realizes in-sensor motion perception and non-contact control beyond perception-memory-processing functions.The self-rectifying device can self-suppress the sneak current in cross-arrays,enabling large-scale and high-density integration.Further integrating synapse with quantum dot light-emitting diodes(QLEDs)evolves more powerful functions like hardware noise filtering and perception-memory-processing-displaying smart systems.
基金EXC 2089:e-conversion DFG-cluster of excellence-TUM innovation network,Technical University of Munich,funded through the German Excellence Initiative and the state of Bavaria(A.G.,M.H.).Support by the project ProperPhotoMile is also gratefully acknowledged(A.G.,I.V-F.),under the umbrella of SOLAR-ERA.NET Cofund 2 by The Spanish Ministry of Science and Education and the AEI under the project PCI2020-112185 and CDTI project number IDI-20210171the Federal Ministry for Economic Affairs and Energy on the basis of a decision by the German Bundestag project number FKZ03EE1070B and FKZ 03EE1070A+2 种基金and the Israel Ministry of Energy with project number 220-11-031SOLAR-ERA.NET is supportedby the European Commission within the EU Framework Programme for Research and Innovation HORIZON 2020(Cofund ERA-NETAction,N 786483)D.K.K.is grateful for the Blaustein postdoctoral fellowship at BGU.R.K.G.is grateful for the Swiss Inst.of Dryland Environmental and Energy Research postdoctoral fellowship at BGU.The authors are also grateful for partial support by the Israel Ministry of Energy,project number 222-11-081.
文摘Imaging offers a fast and accessible means for spatial characterization of halide perovskite photovoltaic materials,yet extracting optoelectrical properties—such as power conversion efficiency(PCE)—remains challenging.This study presents a deep learning methodology that correlates optical reflective images of perovskite solar cells with their PCE by focusing on image differences rather than absolute visual features.The approach predicts relative changes in PCE by comparing images of the same device in different states(e.g.,before and after encapsulation)or against a reference image.This comparative technique significantly outperforms traditional methods that attempt to directly infer PCE from a single image.Furthermore,it demonstrates high effectiveness in low-data regimes,using only 115 samples.By leveraging convolutional neural networks(CNNs)trained on small datasets,the method offers an adaptable and scalable solution for device characterization.Overall,the comparative approach enhances the accuracy and applicability of machine vision in perovskite solar cell analysis.
基金supported by the National Key R&D Program of China(2018YFA0703700 and 2016YFA0200700)the National Natural Science Foundation of China(91964203,61625401,61851403,61974036,61804146,and 61804035)+1 种基金the Strategic Priority Research Program of Chinese Academy of Sciences(XDB30000000)CAS Key Laboratory of Nanosystem and Hierarchical Fabrication.The authors also gratefully acknowledge the support of Youth Innovation Promotion Association CAS.
文摘Exploring materials with multiple properties who can endow a simple device with integrated functionalities has attracted enormous attention in the microelectronic field. One reason is the imperious demand for processors with continuously higher performance and totally new architecture. Combining ferroelectric with semiconducting properties is a promising solution. Here, we show that logic, in-memory computing, and optoelectrical logic and non-volatile computing functionalities can be integrated into a single transistor with ferroelectric semiconducting α-In2Se3 as the channel. Two-input AND, OR, and nonvolatile NOR and NAND logic operations with current on/off ratios reaching up to five orders, good endurance(1000 operation cycles), and fast operating speed(10μs) are realized. In addition, optoelectrical OR logic and non-volatile implication(IMP) operations, as well as ternary-input optoelectrical logic and inmemory computing functions are achieved by introducing light as an additional input signal. Our work highlights the potential of integrating complex logic functions and new-type computing into a simple device based on emerging ferroelectric semiconductors.
文摘In the path toward the realization of carbon nanotube(CNT)-driven electronics and sensors,the ability to precisely position CNTs at well-defined locations remains a significant roadblock.Highly complex CNT-based bottom–up structures can be synthesized if there is a method to accurately trap and place these nanotubes.In this study,we demonstrate that the rapid electrokinetic patterning(REP)technique can accomplish these tasks.By using laser-induced alternating current(AC)electrothermal flow and particle–electrode forces,REP can collect and maneuver a wide range of vertically aligned multiwalled CNTs(from a single nanotube to over 100 nanotubes)on an electrode surface.In addition,these trapped nanotubes can be electrophoretically deposited at any desired location onto the electrode surface.Apart from active control of the position of these deposited nanotubes,the number of CNTs in a REP trap can also be dynamically tuned by changing the AC frequency or by adjusting the concentration of the dispersed nanotubes.On the basis of a calculation of the stiffness of the REP trap,we found an upper limit of the manipulation speed,beyond which CNTs fall out of the REP trap.This peak manipulation speed is found to be dependent on the electrothermal flow velocity,which can be varied by changing the strength of the AC electric field.
基金supported by the National Natural Science Foundation of China(Grant Nos.91436102 and 11374353)and the Fundamental Research Funds for the Central Universities(Grant No.06500067).
文摘Transition metal dichalcogenides(TMDCs)have suitable and adjustable band gaps,high carrier mobility and yield.Layered TMDCs have attracted great attention due to the structure diversity,stable existence in normal temperature environment and the band gap corresponding to wavelength between infrared and visible region.The ultra-thin,flat,almost defect-free surface,excellent mechanical flexibility and chemical stability provide convenient conditions for the construction of different types of TMDCs heterojunctions.The optoelectric properties of heterojunctions based on TMDCs materials are summarized in this review.Special electronic band structures of TMDCs heterojunctions lead to excellent optoelectric properties.The emitter,p-n diodes,photodetectors and photosensitive devices based on TMDCs heterojunction materials show excellent performance.These devices provide a prototype for the design and development of future high-performance optoelectric devices.
