The accuracy of center height detection for corrugated beam guardrails is significantly affected by robot posture in the mobile highway guardrail detection systems based on structured light vision.To address the probl...The accuracy of center height detection for corrugated beam guardrails is significantly affected by robot posture in the mobile highway guardrail detection systems based on structured light vision.To address the problem,this paper proposes an integrated calibration method for structured light vision sensors.In the proposed system,the sensor is mounted on a crawler-type mobile robot,which scans and measures the center height of guardrails while in motion.However,due to external disturbances such as uneven road surfaces and vehicle vibrations,the posture of the robot may deviate,causing displacement of the sensor platform and resulting in spatial 3D measurement errors.To overcome this issue,the system integrates inertial measurement unit(IMU)data into the sensor calibration process,enabling realtime correction of posture deviations through sensor fusion.This approach achieves a unified calibration of the structured light vision system,effectively compensates for posture-induced errors,and enhances detection accuracy.A prototype was developed and tested in both laboratory and real highway environments.Experimental results demonstrate that the proposed method enables accurate center height detection of guardrails under complex road conditions,significantly reduces posture-related measurement errors,and greatly improves the efficiency and reliability of traditional detection methods.展开更多
The utilization of phosphors that achieve full-spectrum lighting has emerged as a prevailing trend in the advancement of white light-emitting diode(WLED)lighting.In this study,we successfully prepared a novel green ph...The utilization of phosphors that achieve full-spectrum lighting has emerged as a prevailing trend in the advancement of white light-emitting diode(WLED)lighting.In this study,we successfully prepared a novel green phosphor Ba_(2)Sc_(2)((BO_(3))_(2)B_(2)O_(5)):Ce^(3+)(BSBO:Ce^(3+))that can be utilized for full-spectrum lighting and low-temperature sensors.BSBO:Ce^(3+)exhibits a broad-band excitation spectrum centered at 410 nm,and a broad-band emission spectrum centered at 525 nm.The internal and external quantum efficiencies of BSBO:Ce^(3+)are 99%and 49%,respectively.The thermal stability of BSBO:Ce^(3+)can be improved by substituting partial Sc atoms with smaller cations.The thermal quenching mechanism of BSBO:Ce^(3+)and the lattice occupancy of Ce ions in BSBO are discussed in detail.Furthermore,by combining the green phosphor BSBO:Ce^(3+),the commercial blue phosphor and the red phosphor on a 405 nm chip,a white light source was obtained with a high average color rendering index(CRI)of 96.6,a low correlated color temperature(CCT)of 3988 K,and a high luminous efficacy of 88.0 Im/W.The lu-minous efficacy of the WLED exhibits negligible degradation during the 1000 h light aging experiment.What's more,an emission peak at 468 nm appears when excited at 352 nm and 80 K,however,the relative intensity of the peaks at 468 and 525 nm gradually weakens with increasing temperature,indicating the potential of this material as a low-temperature sensor.展开更多
Thin alloy films of palladium(Pd) and silver(Ag) are deposited onto glass substrates via the direct current(DC) magnetron technique.The hydrogen sensor probe consists of optical fiber bundle and Pd/Ag optical thin fil...Thin alloy films of palladium(Pd) and silver(Ag) are deposited onto glass substrates via the direct current(DC) magnetron technique.The hydrogen sensor probe consists of optical fiber bundle and Pd/Ag optical thin film.when the sensor is exposed to hydrogen,the refractive index of Pd/Ag optical thin layer will diminish and cause attenuation changes of the reflective light.It is observed that the thickness of Pd/Ag alloy layer can affect the hydrogen sensor signal.Under different substrate temperatures,several Pd/Ag samples are coated with different thicknesses of Pd/Ag alloy,and the results of a hydrogen sensor based on reflective light from the Pd/Ag alloy thin film are discussed.展开更多
This paper presents a novel biosensor for bitter substance detection on the basis of light addressable potentiometric sensor(LAPS).Taste receptor cells(TRCs)were used as sensitive elements,which can respond to differe...This paper presents a novel biosensor for bitter substance detection on the basis of light addressable potentiometric sensor(LAPS).Taste receptor cells(TRCs)were used as sensitive elements,which can respond to different bitter stimuli with extreme high sensitivity and speci-ficity.TRCs were isolated from the taste buds of rats and cultured on the surface of LAPS chip.Due to the unique advantages such as single-cell recording,light addressable capability,and noninvasiveness,LAPS chip was used as secondary transducer to monitor the responses of TRCs by recording extracelluar potential changes.The results indicate LAPS chip can effectively record the responses of TRCs to different bitter substances used in this study in a real-time manner for a long-term.In addition,by performing principal component analysis on the LAPS recording data,different bitter substances tested can be successfully discriminated.It is suggested this TRCsLAPS hybrid biosensor could be a valuable tool for bitter substance detection.With further improvement and novel design,it has great potentials to be applied in both basic research and practical applications related to bitter taste detection.展开更多
Titanium dioxide (TiO2) thin film was deposited on the surface of the light addressable potentiometric sensor (LAPS) to modify the sensor surface for the non-labeled detection of DNA molecules. To evaluate the effect ...Titanium dioxide (TiO2) thin film was deposited on the surface of the light addressable potentiometric sensor (LAPS) to modify the sensor surface for the non-labeled detection of DNA molecules. To evaluate the effect of ultraviolet (UV) treatment on the silanization level of TiO2 thin film by 3-aminopropyltriethoxysilane (APTS),fluorescein isothiocyanate (FITC) was used to label the amine group on the end of APTS immobilized onto the TiO2 thin film. We found that,with UV irradiation,the silanization level of the irradiated area of the TiO2 film was improved compared with the non-irradiated area under well-controlled conditions. This result indicates that TiO2 can act as a coating material on the biosensor surface to improve the effect and efficiency of the covalent immobilization of biomolecules on the sensor surface. The artificially synthesized probe DNA molecules were covalently linked onto the surface of TiO2 film. The hybridization of probe DNA and target DNA was monitored by the recording of I-V curves that shift along the voltage axis during the process of reaction. A significant LAPS signal can be detected at 10 μmol/L of target DNA sample.展开更多
In order to reach the objective of intelligence and energy saving for university classroom lighting, energy saving lighting control system in university classroom based on wireless sensor network is designed, includin...In order to reach the objective of intelligence and energy saving for university classroom lighting, energy saving lighting control system in university classroom based on wireless sensor network is designed, including design of sensor node and sink, as well as corresponding development of control program and upper-computer software. The system sets single-chip Ameg16 as control center, realizes communication between nodes via nRF24L01 wireless transceiver module, and realizes communication between sink and upper computer via w5100 wireless internet module. It perceives illumination intensity via photoconductor, detects the human body position via infrared pyroelectric sensor, and places the sensor node on the lamp, so the light can be controlled according to position of human body and current illumination intensity, which can realize energy saving to a large extent on condition that lighting requirement is satisfied. The system has low cost, and there is no need to change the original lighting circuit. The light can be turned off by hand, and when multi-media are used for the class, light can keep off even it is dim. In addition, this system has the function of automatic fault report, which is convenient for property maintenance.展开更多
A novel light scattering technique for mapping metal surface corrosion is presented and its results on copper exposed to atmosphere are reported. The front end of the instrument is made up of a sensor module comprisin...A novel light scattering technique for mapping metal surface corrosion is presented and its results on copper exposed to atmosphere are reported. The front end of the instrument is made up of a sensor module comprising a thin beam light emitting diode (LED) illuminating a small spot on the metal surface, and a matched pair of photodetectors, one for capturing the reflected light and the other for sampling the scattered light. The analog photocurrent signals are digitized and processed online by a personal computer (PC) to determine the corrosion factor defined in terms of the two current values. By scanning the sample surface using the light beam and by computing the corrosion factor values simultaneously, a three dimensional graph and a two dimensional contour map are generated in the PC using Matlab tools. The values of the corrosion factor measured in different durations of exposure to atmosphere, which obey a bilogarithmic law, testify to the validity of our mathematical model.展开更多
In this study, “homeostasis”, the function by which living things keep their constancy, was emulated as a lighting control for a building space. The algorithm we developed mimics the mechanisms of the endocrine and ...In this study, “homeostasis”, the function by which living things keep their constancy, was emulated as a lighting control for a building space. The algorithm we developed mimics the mechanisms of the endocrine and immune systems. The endocrine system transmits information entirely, whereas the immune system transmits information with a concentration gradient. A lighting control system using the proposed algorithm was evaluated in a simulation and experiment using a sensor agent robot. In this algorithm, a robot recognizes a person’s behavior and uses it to decide his or her preference as to the illuminance. The results indicate that the algorithm can be used to realize a comfortable lighting control in several situations.展开更多
<正>A novel neurochip based on light addressable potentiometric sensor (LAPS) is designed.Using its light addressable characteristic.The problems of the limitations of restricted discrete active sites of current...<正>A novel neurochip based on light addressable potentiometric sensor (LAPS) is designed.Using its light addressable characteristic.The problems of the limitations of restricted discrete active sites of current neurochips,such as microelectrode array and field effect transistor array can be settled easily.Based on the theoretical analysis of the interface between cells and LAPS,spontaneously discharges of hippocampal neurons induced by Mg~ 2+)-free media treatment were recorded by LAPS.The results demonstrate that this kind of neurochip has potential to monitor electrophysiology of cultured cells in a non-invasive way.展开更多
Flexible piezoresistive sensors based on carbon nanomaterials have attracted significant attention with regard to their application to wearable electronics.The enhanced performance of these sensors is primarily due to...Flexible piezoresistive sensors based on carbon nanomaterials have attracted significant attention with regard to their application to wearable electronics.The enhanced performance of these sensors is primarily due to the integration of microstructures and conductive coatings.In this study,a flexible sandwich-shaped piezoresistive pressure sensor is fabricated by adopting microstructured electrodes and a porous sensing layer of carbon nanocomposite.The microtextured electrodes are obtained from a template by three-dimensional printing using digital light processing(DLP),and the porous structure is obtained by scarification of an NaCl crystal template.Multiwalled carbon nanotubes(MWCNTs)and graphene nanoparticles(GNPs),composited with polydimethylsiloxane and silica(ESSIL 296),are used to fabricate the functional structures,including the upper and lower electrode layers and a sandwiched porous sensing layer.The sensor exhibits a rapid response and recovery speed(-80 ms),a high sensitivity(0.437 kPa^(−1))within a range of 0–1.08 kPa,and excellent stability.In addition,such sensors demonstrate potential applications for finger motion monitoring and information encryption.展开更多
Nitrogen dioxide(NO2),a hazardous gas with acidic nature,is continuously being liberated in the atmosphere due to human activity.The NO2 sensors based on traditional materials have limitations of high-temperature requ...Nitrogen dioxide(NO2),a hazardous gas with acidic nature,is continuously being liberated in the atmosphere due to human activity.The NO2 sensors based on traditional materials have limitations of high-temperature requirements,slow recovery,and performance degradation under harsh environmental conditions.These limitations of traditional materials are forcing the scientific community to discover future alternative NO2 sensitive materials.Molybdenum disulfide(MoS2)has emerged as a potential candidate for developing next-generation NO2 gas sensors.MoS2 has a large surface area for NO2 molecules adsorption with controllable morphologies,facile integration with other materials and compatibility with internet of things(IoT)devices.The aim of this review is to provide a detailed overview of the fabrication of MoS2 chemiresistance sensors in terms of devices(resistor and transistor),layer thickness,morphology control,defect tailoring,heterostructure,metal nanoparticle doping,and through light illumination.Moreover,the experimental and theoretical aspects used in designing MoS2-based NO2 sensors are also discussed extensively.Finally,the review concludes the challenges and future perspectives to further enhance the gas-sensing performance of MoS2.Understanding and addressing these issues are expected to yield the development of highly reliable and industry standard chemiresistance NO2 gas sensors for environmental monitoring.展开更多
Currently,SmFeO_(3)-based sensors are an effective platform for detecting acetone gas.However,they require high operating temperatures,which increases energy consumption and safety hazards,and their response is low wh...Currently,SmFeO_(3)-based sensors are an effective platform for detecting acetone gas.However,they require high operating temperatures,which increases energy consumption and safety hazards,and their response is low when the gas concentration is at 10^(-9)(PPB),which cannot meet the requirements of using exhaled breath to pre-diagnose diabetes.Herein,Pd-SmFeO_(3)hollow nanotubes with an extremely high specific surface area and porosity were synthesized by electrospinning.After Pd doping,the specific surface area improved by more than two times,and the acetone response improved by more than three times.In addition,the response further improved by more than 1.5 times,and the optimum operating temperature reduced by 100℃under light irradiation.Moreover,the relative humidity adaptability,long-term stability,and selectivity of the material were significantly improved after Pd doping or light irradiation.Finally,the acetone concentration in a person’s exhaled breath was detected by a Pd-SmFeO_(3)-based gas sensor,and the error was less than 10%compared to that obtained by gas chromatography-mass spectrometry method.展开更多
In this study,we have developed a high-sensitivity,near-infrared photodetector based on PdSe2/GaAs heterojunction,which was made by transferring a multilayered PdSe2 film onto a planar GaAs.The as-fabricated PdSe2/GaA...In this study,we have developed a high-sensitivity,near-infrared photodetector based on PdSe2/GaAs heterojunction,which was made by transferring a multilayered PdSe2 film onto a planar GaAs.The as-fabricated PdSe2/GaAs heterojunction device exhibited obvious photovoltaic behavior to 808 nm illumination,indicating that the near-infrared photodetector can be used as a self-driven device without external power supply.Further device analysis showed that the hybrid heterojunction exhibited a high on/off ratio of 1.16×10^5 measured at 808 nm under zero bias voltage.The responsivity and specific detectivity of photodetector were estimated to be 171.34 mA/W and 2.36×10^11 Jones,respectively.Moreover,the device showed excellent stability and reliable repeatability.After 2 months,the photoelectric characteristics of the near-infrared photodetector hardly degrade in air,attributable to the good stability of the PdSe2.Finally,the PdSe2/GaAs-based heterojunction device can also function as a near-infrared light sensor.展开更多
基金Supported by the Special Fund for Basic Scientific Research of Central-Level Public Welfare Scientific Research Institutes(2024-9007)。
文摘The accuracy of center height detection for corrugated beam guardrails is significantly affected by robot posture in the mobile highway guardrail detection systems based on structured light vision.To address the problem,this paper proposes an integrated calibration method for structured light vision sensors.In the proposed system,the sensor is mounted on a crawler-type mobile robot,which scans and measures the center height of guardrails while in motion.However,due to external disturbances such as uneven road surfaces and vehicle vibrations,the posture of the robot may deviate,causing displacement of the sensor platform and resulting in spatial 3D measurement errors.To overcome this issue,the system integrates inertial measurement unit(IMU)data into the sensor calibration process,enabling realtime correction of posture deviations through sensor fusion.This approach achieves a unified calibration of the structured light vision system,effectively compensates for posture-induced errors,and enhances detection accuracy.A prototype was developed and tested in both laboratory and real highway environments.Experimental results demonstrate that the proposed method enables accurate center height detection of guardrails under complex road conditions,significantly reduces posture-related measurement errors,and greatly improves the efficiency and reliability of traditional detection methods.
基金the National Natural Science Foundation of China(22003035,21963006,22073061)the Project of Shaanxi Province Youth Science and Technology New Star(2023KJXX-076)the National Training Program of Innovation and Entrepreneurship for Undergraduates(202314390018)。
文摘The utilization of phosphors that achieve full-spectrum lighting has emerged as a prevailing trend in the advancement of white light-emitting diode(WLED)lighting.In this study,we successfully prepared a novel green phosphor Ba_(2)Sc_(2)((BO_(3))_(2)B_(2)O_(5)):Ce^(3+)(BSBO:Ce^(3+))that can be utilized for full-spectrum lighting and low-temperature sensors.BSBO:Ce^(3+)exhibits a broad-band excitation spectrum centered at 410 nm,and a broad-band emission spectrum centered at 525 nm.The internal and external quantum efficiencies of BSBO:Ce^(3+)are 99%and 49%,respectively.The thermal stability of BSBO:Ce^(3+)can be improved by substituting partial Sc atoms with smaller cations.The thermal quenching mechanism of BSBO:Ce^(3+)and the lattice occupancy of Ce ions in BSBO are discussed in detail.Furthermore,by combining the green phosphor BSBO:Ce^(3+),the commercial blue phosphor and the red phosphor on a 405 nm chip,a white light source was obtained with a high average color rendering index(CRI)of 96.6,a low correlated color temperature(CCT)of 3988 K,and a high luminous efficacy of 88.0 Im/W.The lu-minous efficacy of the WLED exhibits negligible degradation during the 1000 h light aging experiment.What's more,an emission peak at 468 nm appears when excited at 352 nm and 80 K,however,the relative intensity of the peaks at 468 and 525 nm gradually weakens with increasing temperature,indicating the potential of this material as a low-temperature sensor.
基金supported by the National Natural Science Foundation of China (No.50974062)the National Science and Technology Major Projects of China (No.2009ZX04002-043-05)+1 种基金the Scientific Research Program of Department of Education of Henan Province of China (No.2008B520044)the Basic and Frontier Technology Research Program of Henan Province of China (No.082300410320)
文摘Thin alloy films of palladium(Pd) and silver(Ag) are deposited onto glass substrates via the direct current(DC) magnetron technique.The hydrogen sensor probe consists of optical fiber bundle and Pd/Ag optical thin film.when the sensor is exposed to hydrogen,the refractive index of Pd/Ag optical thin layer will diminish and cause attenuation changes of the reflective light.It is observed that the thickness of Pd/Ag alloy layer can affect the hydrogen sensor signal.Under different substrate temperatures,several Pd/Ag samples are coated with different thicknesses of Pd/Ag alloy,and the results of a hydrogen sensor based on reflective light from the Pd/Ag alloy thin film are discussed.
基金This work was supported by the grants from the National Natural Science Foundation of China(Grant Nos.60725102,31000448)the China Postdoctoral Science Foundation(Grant Nos.20100471737,201104734)the Key Project of Zhejiang Province(Grant No.2010C14006).
文摘This paper presents a novel biosensor for bitter substance detection on the basis of light addressable potentiometric sensor(LAPS).Taste receptor cells(TRCs)were used as sensitive elements,which can respond to different bitter stimuli with extreme high sensitivity and speci-ficity.TRCs were isolated from the taste buds of rats and cultured on the surface of LAPS chip.Due to the unique advantages such as single-cell recording,light addressable capability,and noninvasiveness,LAPS chip was used as secondary transducer to monitor the responses of TRCs by recording extracelluar potential changes.The results indicate LAPS chip can effectively record the responses of TRCs to different bitter substances used in this study in a real-time manner for a long-term.In addition,by performing principal component analysis on the LAPS recording data,different bitter substances tested can be successfully discriminated.It is suggested this TRCsLAPS hybrid biosensor could be a valuable tool for bitter substance detection.With further improvement and novel design,it has great potentials to be applied in both basic research and practical applications related to bitter taste detection.
基金Project supported by the National Natural Science Foundation of China (Nos. 30627002 and 60725102)the Interdisciplinary Research Foundation of Zhejiang University (No. 2009-15), China
文摘Titanium dioxide (TiO2) thin film was deposited on the surface of the light addressable potentiometric sensor (LAPS) to modify the sensor surface for the non-labeled detection of DNA molecules. To evaluate the effect of ultraviolet (UV) treatment on the silanization level of TiO2 thin film by 3-aminopropyltriethoxysilane (APTS),fluorescein isothiocyanate (FITC) was used to label the amine group on the end of APTS immobilized onto the TiO2 thin film. We found that,with UV irradiation,the silanization level of the irradiated area of the TiO2 film was improved compared with the non-irradiated area under well-controlled conditions. This result indicates that TiO2 can act as a coating material on the biosensor surface to improve the effect and efficiency of the covalent immobilization of biomolecules on the sensor surface. The artificially synthesized probe DNA molecules were covalently linked onto the surface of TiO2 film. The hybridization of probe DNA and target DNA was monitored by the recording of I-V curves that shift along the voltage axis during the process of reaction. A significant LAPS signal can be detected at 10 μmol/L of target DNA sample.
文摘In order to reach the objective of intelligence and energy saving for university classroom lighting, energy saving lighting control system in university classroom based on wireless sensor network is designed, including design of sensor node and sink, as well as corresponding development of control program and upper-computer software. The system sets single-chip Ameg16 as control center, realizes communication between nodes via nRF24L01 wireless transceiver module, and realizes communication between sink and upper computer via w5100 wireless internet module. It perceives illumination intensity via photoconductor, detects the human body position via infrared pyroelectric sensor, and places the sensor node on the lamp, so the light can be controlled according to position of human body and current illumination intensity, which can realize energy saving to a large extent on condition that lighting requirement is satisfied. The system has low cost, and there is no need to change the original lighting circuit. The light can be turned off by hand, and when multi-media are used for the class, light can keep off even it is dim. In addition, this system has the function of automatic fault report, which is convenient for property maintenance.
文摘A novel light scattering technique for mapping metal surface corrosion is presented and its results on copper exposed to atmosphere are reported. The front end of the instrument is made up of a sensor module comprising a thin beam light emitting diode (LED) illuminating a small spot on the metal surface, and a matched pair of photodetectors, one for capturing the reflected light and the other for sampling the scattered light. The analog photocurrent signals are digitized and processed online by a personal computer (PC) to determine the corrosion factor defined in terms of the two current values. By scanning the sample surface using the light beam and by computing the corrosion factor values simultaneously, a three dimensional graph and a two dimensional contour map are generated in the PC using Matlab tools. The values of the corrosion factor measured in different durations of exposure to atmosphere, which obey a bilogarithmic law, testify to the validity of our mathematical model.
文摘In this study, “homeostasis”, the function by which living things keep their constancy, was emulated as a lighting control for a building space. The algorithm we developed mimics the mechanisms of the endocrine and immune systems. The endocrine system transmits information entirely, whereas the immune system transmits information with a concentration gradient. A lighting control system using the proposed algorithm was evaluated in a simulation and experiment using a sensor agent robot. In this algorithm, a robot recognizes a person’s behavior and uses it to decide his or her preference as to the illuminance. The results indicate that the algorithm can be used to realize a comfortable lighting control in several situations.
基金supported by the National Natural Science Foundation of China(Grant Nos.30270387,No.30570492)the Project of State Key Laboratory of Transducer Technology of China(Grant No.SKT0403)the Foundation for the Bureau of Zhejiang Province of China(Grant No.20040197).
文摘<正>A novel neurochip based on light addressable potentiometric sensor (LAPS) is designed.Using its light addressable characteristic.The problems of the limitations of restricted discrete active sites of current neurochips,such as microelectrode array and field effect transistor array can be settled easily.Based on the theoretical analysis of the interface between cells and LAPS,spontaneously discharges of hippocampal neurons induced by Mg~ 2+)-free media treatment were recorded by LAPS.The results demonstrate that this kind of neurochip has potential to monitor electrophysiology of cultured cells in a non-invasive way.
基金supported by the Science and Technology Cooperation and Exchange Special Project of Shanxi Province(Grant No.202204041101006)the Shanxi Provincial Patent Transformation Special Plan Project(Grant No.202403003)+4 种基金a research project supported by the Shanxi Scholarship Council of China(Grant No.2023-130)the Aeronautical Science Foundation of China(Grant No.2023Z0560U0001)the Fundamental Research Program of Shanxi Province(Grant No.202203021222077)the Science and Technology Project of the North University of China(Grant No.20231914)the National Natural Science Foundation of China(Grant Nos.52405633 and 62404208).
文摘Flexible piezoresistive sensors based on carbon nanomaterials have attracted significant attention with regard to their application to wearable electronics.The enhanced performance of these sensors is primarily due to the integration of microstructures and conductive coatings.In this study,a flexible sandwich-shaped piezoresistive pressure sensor is fabricated by adopting microstructured electrodes and a porous sensing layer of carbon nanocomposite.The microtextured electrodes are obtained from a template by three-dimensional printing using digital light processing(DLP),and the porous structure is obtained by scarification of an NaCl crystal template.Multiwalled carbon nanotubes(MWCNTs)and graphene nanoparticles(GNPs),composited with polydimethylsiloxane and silica(ESSIL 296),are used to fabricate the functional structures,including the upper and lower electrode layers and a sandwiched porous sensing layer.The sensor exhibits a rapid response and recovery speed(-80 ms),a high sensitivity(0.437 kPa^(−1))within a range of 0–1.08 kPa,and excellent stability.In addition,such sensors demonstrate potential applications for finger motion monitoring and information encryption.
基金the Department of Atomic Energy(DAE)under Project No.34/20/09/2015/BRNSthe Department of Physics,IIT Ropar for providing financial support and the research facility。
文摘Nitrogen dioxide(NO2),a hazardous gas with acidic nature,is continuously being liberated in the atmosphere due to human activity.The NO2 sensors based on traditional materials have limitations of high-temperature requirements,slow recovery,and performance degradation under harsh environmental conditions.These limitations of traditional materials are forcing the scientific community to discover future alternative NO2 sensitive materials.Molybdenum disulfide(MoS2)has emerged as a potential candidate for developing next-generation NO2 gas sensors.MoS2 has a large surface area for NO2 molecules adsorption with controllable morphologies,facile integration with other materials and compatibility with internet of things(IoT)devices.The aim of this review is to provide a detailed overview of the fabrication of MoS2 chemiresistance sensors in terms of devices(resistor and transistor),layer thickness,morphology control,defect tailoring,heterostructure,metal nanoparticle doping,and through light illumination.Moreover,the experimental and theoretical aspects used in designing MoS2-based NO2 sensors are also discussed extensively.Finally,the review concludes the challenges and future perspectives to further enhance the gas-sensing performance of MoS2.Understanding and addressing these issues are expected to yield the development of highly reliable and industry standard chemiresistance NO2 gas sensors for environmental monitoring.
基金financially supported by Shandong Natural Science Foundation(No.ZR2021QE265)the Fundamental Research Funds of Taishan University(No.Y01-2020015)+1 种基金the National Natural Science Foundation of China(Nos.61574098,61204051)Shandong Province Key Research and Development Program(No.2019GGX101016)。
文摘Currently,SmFeO_(3)-based sensors are an effective platform for detecting acetone gas.However,they require high operating temperatures,which increases energy consumption and safety hazards,and their response is low when the gas concentration is at 10^(-9)(PPB),which cannot meet the requirements of using exhaled breath to pre-diagnose diabetes.Herein,Pd-SmFeO_(3)hollow nanotubes with an extremely high specific surface area and porosity were synthesized by electrospinning.After Pd doping,the specific surface area improved by more than two times,and the acetone response improved by more than three times.In addition,the response further improved by more than 1.5 times,and the optimum operating temperature reduced by 100℃under light irradiation.Moreover,the relative humidity adaptability,long-term stability,and selectivity of the material were significantly improved after Pd doping or light irradiation.Finally,the acetone concentration in a person’s exhaled breath was detected by a Pd-SmFeO_(3)-based gas sensor,and the error was less than 10%compared to that obtained by gas chromatography-mass spectrometry method.
基金supported by the National Natural Science Foundation of China(No.61575059,No.61675062,No.21501038)the Fundamental Research Funds for the Central Universities(No.JZ2018HGPB0275,No.JZ2018HGTA0220,and No.JZ2018HGXC0001).
文摘In this study,we have developed a high-sensitivity,near-infrared photodetector based on PdSe2/GaAs heterojunction,which was made by transferring a multilayered PdSe2 film onto a planar GaAs.The as-fabricated PdSe2/GaAs heterojunction device exhibited obvious photovoltaic behavior to 808 nm illumination,indicating that the near-infrared photodetector can be used as a self-driven device without external power supply.Further device analysis showed that the hybrid heterojunction exhibited a high on/off ratio of 1.16×10^5 measured at 808 nm under zero bias voltage.The responsivity and specific detectivity of photodetector were estimated to be 171.34 mA/W and 2.36×10^11 Jones,respectively.Moreover,the device showed excellent stability and reliable repeatability.After 2 months,the photoelectric characteristics of the near-infrared photodetector hardly degrade in air,attributable to the good stability of the PdSe2.Finally,the PdSe2/GaAs-based heterojunction device can also function as a near-infrared light sensor.
