The application of NO_(2)sensor reduces the emission of NO_(2)from the industry and automotive vehicles.However,insufficient electrocatalytic activity and adsorption to NO_(2)of sensing electrode(SE)limit the sensitiv...The application of NO_(2)sensor reduces the emission of NO_(2)from the industry and automotive vehicles.However,insufficient electrocatalytic activity and adsorption to NO_(2)of sensing electrode(SE)limit the sensitivity increment of NO_(2)sensor.Thus,a novel ZnWO_(4)/Li_(6)W_(2)O_(9)heterojunction SE is constructed by molten salt method for the zirconia-based impedancemetric NO_(2)sensor.The influence of the ZnWO_(4)/Li_(6)W_(2)O_(9)ratio on the performance of the sensor is investigated.The results show that Li_(6)W_(2)O_(9)in-situ formation on the surface of the ZnWO_(4)in LiNO_(3)molten at a low temperature of 300℃.The incorporation of Li_(6)W_(2)O_(9)enhances both the adsorption property and electrocatalytic activity of the SE,simultaneously,resulting in a significant increase in the sensitivity of sensor.The sensitivity increases gradually with the increasing incorporation of Li_(6)W_(2)O_(9).The sensitivity of ZnWO_(4)/37.5%Li_(6)W_(2)O_(9)sensor is significantly increased by 124%compared to the pristine ZnWO_(4)sensor and exhibits the largest sensitivity of 25.19(°)decade-1at 400℃.Moreover,the ZnWO_(4)/Li_(6)W_(2)O_(9)sensor also displays excellent selectivity,long-term stability,and repeatability.The introduction of in-situ formation by molten salt method is an effective strategy to develop gas sensors with large sensitivity.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
Polythiophene （PTP） was prepared by a chemical oxidative polymerization and nanosized WO3 was prepared by a colloidal chemical method. The organic-inorganic PTP/WO3 hybrids with different mass fractions of PTP were ...Polythiophene （PTP） was prepared by a chemical oxidative polymerization and nanosized WO3 was prepared by a colloidal chemical method. The organic-inorganic PTP/WO3 hybrids with different mass fractions of PTP were obtained by a simple mechanically mixing the prepared PTP and WO3. The as-prepared PTP/WO3 hybrids have a higher thermal stability than the pure PTP. The gas sensing measurements demonstrate that the PTP/WO3 hybrid sensors exhibit higher response for detecting NO2 at low temperature than the pure PTP and WO3 sensor. The sensing mechanism is suggested to be related to the existence of p-n heterojunctions in the PTP/WO3 hybrids. The response of the PTP/WO3 hybrids is markedly influenced by the PTP mass fraction. The 20% PTP/WO3 hybrid shows high response and good selectivity to NO2 at low temperature （〈90℃）. Therefore, the PTP/WO3 hybrids can be expected to be potentially used as gas sensor material for detecting NO2 at low temperature.展开更多
Environmentally friendly degradable sensors with both hazardous gases and pressure efficient sensing capabilities are highly desired for various promising applications,including environmental pollution monitoring/prev...Environmentally friendly degradable sensors with both hazardous gases and pressure efficient sensing capabilities are highly desired for various promising applications,including environmental pollution monitoring/prevention,wisdom medical,wearable smart devices,and artificial intelligence.However,the transient gas and pressure sensors based on only identical sensing material that concurrently meets the above detection needs have not been reported.Here,we present transient all-MXene NO_(2) and pressure sensors employing three-dimensional porous crumpled MXene spheres prepared by ultrasonic spray pyrolysis technology as the sensing layer,accompanied with water-soluble polyvinyl alcohol substrates embedded with patterned MXene electrodes.The gas sensor achieves a ppb-level of highly selective NO_(2) sensing,with a response of up to 12.11%at 5 ppm NO_(2) and a detection range of 50 ppb-5 ppm,while the pressure sensor has an extremely wide linear pressure detection range of 0.14-22.22 kPa and fast response time of 34 ms.In parallel,all-MXene NO_(2) and pressure sensors can be rapidly degraded in medical H_(2)O_(2) within 6 h.This work provides a new avenue toward environmental monitoring,human physiological signal monitoring,and recyclable transient electronics.展开更多
The paper presents a new method for fabricating a gas-sensitive micro-sensor based on MEMS.The primary target agents are nitrogen dioxides (NO_2),and DIMP.Past-per-billion concentration levels of these two chemicals c...The paper presents a new method for fabricating a gas-sensitive micro-sensor based on MEMS.The primary target agents are nitrogen dioxides (NO_2),and DIMP.Past-per-billion concentration levels of these two chemicals can be detected.An interdigitated gate electrode field-effect transistor (IGEFET) has been coupled with a chemically-active and electron-beam evaporated copper phthaiocyanine (CuPc) thin film to implement a gas-sensitive micro-sensor.The sensor is excited with voltage pulse.Time and frequency-domain response were measured.The magnitude of the normalized difference Fourier transform is distinct distinguished.展开更多
Based on conventional metal-oxide-semiconductor field-effect transistor (MOSFET),a novel kind of chemical field-effect transistor (ChemFET) gas sensor array has been designed and fabricated.The obtained sensor consist...Based on conventional metal-oxide-semiconductor field-effect transistor (MOSFET),a novel kind of chemical field-effect transistor (ChemFET) gas sensor array has been designed and fabricated.The obtained sensor consists of self-assembly polyaniline (PAN) composite film containing poly(acrylic acid) (PAA) which was used as gate material of MOSFET instead of conventional metallic gate.The UV-Vis absorption spectra of PAN/PAA films were characterized.The NO_2 gas sensitive property of the ChemFET sensor array was also investigated.Results show that the drain current of devices increases with increasing of back-side voltage,and decreases with the increase of NO_2 concentration when the NO_2 concentration is below 20μg/g.The temperature dependence of ChemFET sensor array shows that the drain current of ChemFET sensor decreases with increasing of temperature.展开更多
基金financially supported by the National Natural Science Foundation of China(No.52371187)the Innovation Capacity Enhancement Projects of Hebei Province(Nos.24461002D and 22567608H)+3 种基金the Natural Science Foundation of Hebei Province(Nos.E2024209044 and B2022209018)the Science and Technology Planning Project of Tangshan City(No.22130215G)Tangshan Talent Grant Program(No.A202202006)the Youth Scholars Promotion Plan of North China University of Science and Technology(No.QNTJ202206)
文摘The application of NO_(2)sensor reduces the emission of NO_(2)from the industry and automotive vehicles.However,insufficient electrocatalytic activity and adsorption to NO_(2)of sensing electrode(SE)limit the sensitivity increment of NO_(2)sensor.Thus,a novel ZnWO_(4)/Li_(6)W_(2)O_(9)heterojunction SE is constructed by molten salt method for the zirconia-based impedancemetric NO_(2)sensor.The influence of the ZnWO_(4)/Li_(6)W_(2)O_(9)ratio on the performance of the sensor is investigated.The results show that Li_(6)W_(2)O_(9)in-situ formation on the surface of the ZnWO_(4)in LiNO_(3)molten at a low temperature of 300℃.The incorporation of Li_(6)W_(2)O_(9)enhances both the adsorption property and electrocatalytic activity of the SE,simultaneously,resulting in a significant increase in the sensitivity of sensor.The sensitivity increases gradually with the increasing incorporation of Li_(6)W_(2)O_(9).The sensitivity of ZnWO_(4)/37.5%Li_(6)W_(2)O_(9)sensor is significantly increased by 124%compared to the pristine ZnWO_(4)sensor and exhibits the largest sensitivity of 25.19(°)decade-1at 400℃.Moreover,the ZnWO_(4)/Li_(6)W_(2)O_(9)sensor also displays excellent selectivity,long-term stability,and repeatability.The introduction of in-situ formation by molten salt method is an effective strategy to develop gas sensors with large sensitivity.
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Foundation item: Project (21171099) supported by the National Natural Science Foundation of ChinaProjects (09JCYBJC03600,10JCYBJC03900) supported by Technology Commission Foundation of Tianjin,China
文摘Polythiophene （PTP） was prepared by a chemical oxidative polymerization and nanosized WO3 was prepared by a colloidal chemical method. The organic-inorganic PTP/WO3 hybrids with different mass fractions of PTP were obtained by a simple mechanically mixing the prepared PTP and WO3. The as-prepared PTP/WO3 hybrids have a higher thermal stability than the pure PTP. The gas sensing measurements demonstrate that the PTP/WO3 hybrid sensors exhibit higher response for detecting NO2 at low temperature than the pure PTP and WO3 sensor. The sensing mechanism is suggested to be related to the existence of p-n heterojunctions in the PTP/WO3 hybrids. The response of the PTP/WO3 hybrids is markedly influenced by the PTP mass fraction. The 20% PTP/WO3 hybrid shows high response and good selectivity to NO2 at low temperature （〈90℃）. Therefore, the PTP/WO3 hybrids can be expected to be potentially used as gas sensor material for detecting NO2 at low temperature.
基金supported by the National Nature Science Foundation of China(Nos.62122030,61831011,61803171,61722305,61833006,and 21902057)Program for Chang Jiang Scholars and Innovative Research Team in University(No.IRT-17R47)+3 种基金Application and Basic Research of Jilin Province(20130102010 JC)Young Elite Scientists Sponsorship Program by CAST(2018QN RC001)Jilin Province Science and Technology Development Plan Program(20200301010RQ)Fundamental Research Funds for the Central Universities,Graduate Innovation Fund of Jilin University(101832020CX170).
文摘Environmentally friendly degradable sensors with both hazardous gases and pressure efficient sensing capabilities are highly desired for various promising applications,including environmental pollution monitoring/prevention,wisdom medical,wearable smart devices,and artificial intelligence.However,the transient gas and pressure sensors based on only identical sensing material that concurrently meets the above detection needs have not been reported.Here,we present transient all-MXene NO_(2) and pressure sensors employing three-dimensional porous crumpled MXene spheres prepared by ultrasonic spray pyrolysis technology as the sensing layer,accompanied with water-soluble polyvinyl alcohol substrates embedded with patterned MXene electrodes.The gas sensor achieves a ppb-level of highly selective NO_(2) sensing,with a response of up to 12.11%at 5 ppm NO_(2) and a detection range of 50 ppb-5 ppm,while the pressure sensor has an extremely wide linear pressure detection range of 0.14-22.22 kPa and fast response time of 34 ms.In parallel,all-MXene NO_(2) and pressure sensors can be rapidly degraded in medical H_(2)O_(2) within 6 h.This work provides a new avenue toward environmental monitoring,human physiological signal monitoring,and recyclable transient electronics.
基金This project was supported by National Science Foundation of the U.S. under fund cite NSF 03-512. And it is supported by National Science Foundation of China+1 种基金 under fund cite NSFC 60272002. National ‘863 Project＇ of China under fund cite A05106AA5114.
文摘The paper presents a new method for fabricating a gas-sensitive micro-sensor based on MEMS.The primary target agents are nitrogen dioxides (NO_2),and DIMP.Past-per-billion concentration levels of these two chemicals can be detected.An interdigitated gate electrode field-effect transistor (IGEFET) has been coupled with a chemically-active and electron-beam evaporated copper phthaiocyanine (CuPc) thin film to implement a gas-sensitive micro-sensor.The sensor is excited with voltage pulse.Time and frequency-domain response were measured.The magnitude of the normalized difference Fourier transform is distinct distinguished.
基金This work is supported by the National Science Foundation of China （Grants No. 60372002, 60425101）
文摘Based on conventional metal-oxide-semiconductor field-effect transistor (MOSFET),a novel kind of chemical field-effect transistor (ChemFET) gas sensor array has been designed and fabricated.The obtained sensor consists of self-assembly polyaniline (PAN) composite film containing poly(acrylic acid) (PAA) which was used as gate material of MOSFET instead of conventional metallic gate.The UV-Vis absorption spectra of PAN/PAA films were characterized.The NO_2 gas sensitive property of the ChemFET sensor array was also investigated.Results show that the drain current of devices increases with increasing of back-side voltage,and decreases with the increase of NO_2 concentration when the NO_2 concentration is below 20μg/g.The temperature dependence of ChemFET sensor array shows that the drain current of ChemFET sensor decreases with increasing of temperature.
