The influence of structural design and the parameters of the working electrode on the response time of a solid polymer electrolyte (SPE) carbon monoxide sensor has been studied. Results show that the response time is ...The influence of structural design and the parameters of the working electrode on the response time of a solid polymer electrolyte (SPE) carbon monoxide sensor has been studied. Results show that the response time is mainly determined by the RC time constant of the catalyst layer and also related with the working electrode potential.展开更多
Carbon monoxide (CO) is a gaseous mediator, which is generated via anenzymatic reaction of heme oxygenase, and it plays physiological roles to regulate cellular respiration and blood flow in the liver. The concentrati...Carbon monoxide (CO) is a gaseous mediator, which is generated via anenzymatic reaction of heme oxygenase, and it plays physiological roles to regulate cellular respiration and blood flow in the liver. The concentration and distribution of CO molecules in the living body is unknown owing to a lack of a suitable technique for measuring them in vivo. A needle-type CO sensor has been used for bioinstrumentation, but it is inappropriate for implantation in vivo and long-term monitoring. We developed a CO sensor sheet based on hemoglobin (Hb) allostery, as Hb undergoes a conformational change on CO binding. Hb was extracted from mice blood and mixed with agarose gel with a reducer to stabilize deoxy-Hb in the gel. CO-releasing molecules (CORM) were used to mimic CO-generating tissue, and the sensitivity of the Hb gel could be regulated by Hb concentration. We defined the CO–Hb index, an absorbance ratio at 539 and 557 nm, to estimate the accumulation of captured CO in the gel. It correlatively increased with CORM dose, indicating that gel-embedded Hb underwent a conformational change on CO binding, thereby acting as a CO sensor. We subsequently used the Hb-sensor sheet for two-dimensional imaging of CO distribution. CORM-containing gels with different sizes and doses were layered on this sheet. Size- and dose-dependent CO distribution was visualized by scanning the CO-Hb index in the sheet. Our Hb-based CO sensor sheet is composed of biocompatible materials and can be applied to detect low-level CO sources in the living body.展开更多
An optical fiber dual Fabry-Perot interferometric carbon monoxide gas sensor based on PANI/Co3 O4/GO(PCG)sensing membrane coated on the end face of the optical fiber is proposed and fabricated.One end face of photonic...An optical fiber dual Fabry-Perot interferometric carbon monoxide gas sensor based on PANI/Co3 O4/GO(PCG)sensing membrane coated on the end face of the optical fiber is proposed and fabricated.One end face of photonic crystal fiber(PCF)without cut-off wavelength is fused with a single-mode fiber(SMF),and the other end face of the PCF is coated with PCG sensing membrane.The collapsed layer formed during the air hole fusion of PCF is used as the first reflector,the interface between PCF and sensing membrane is used as the second reflector,and the interface between the sensing membrane and the air is used as the third reflector,thus the dual Fabry-Pe rot structure sensor is formed.The results show that the sensor has excellent sensitivity and selectivity to carbon monoxide.With the increasing concentration of carbon monoxide gas in the range of 0-60 ppm,the intensity of interference spectrum decreases.The sensitivity of the sensor is 0.3473 dB m/ppm,and its linearity is good.The response time and recovery time are 68 s and 106 s,respectively.The sensor has the advantages of the compact size,low cost,high sensitivity,strong selectivity and simple structure.It is suitable for the sensing detection of low concentration carbon monoxide gas.展开更多
A carbon monoxide gas sensor based on single-walled carbon nanotube （SWCNT） has been developed for detection of carbon monoxide （CO） at room temperature. Copper chloride （CuC1） was mixed with SWNT by mechanical ...A carbon monoxide gas sensor based on single-walled carbon nanotube （SWCNT） has been developed for detection of carbon monoxide （CO） at room temperature. Copper chloride （CuC1） was mixed with SWNT by mechanical blending. The thin film was deposited on interdigitated electrodes by using airbrush technology. This paper described the fabrication of the sensor for detecting carbon monoxide with concentrations from 20 ppm to 100 ppm. The performance of CO gas sensor was measured by using relevant apparatus to obtain the continuous sensor electric resistance change on exposure to CO and air atmosphere at room temperature, respectively. The results exhibited that the senor presented a larger sensitivity and a good recoverability. The experimental results suggested the potential use of CuC1 doped SWCNT for CO detecting.展开更多
The use of heterojunctions is a promising solution to the problem of cross-sensitivity in gas sensors.In this work,a carbon monoxide sensor based on the CuO/TiO_(2)heterojunction was designed and fabricated.Due to the...The use of heterojunctions is a promising solution to the problem of cross-sensitivity in gas sensors.In this work,a carbon monoxide sensor based on the CuO/TiO_(2)heterojunction was designed and fabricated.Due to the good adsorption properties of CuO materials to CO,and the heterojunction interface charge transfer,the CuO/TiO_(2)thin film sensor exhibits high sensitivity to CO at room temperature.The response is as high as 10.8–200 ppm CO,about 10 times its response to H_(2).Interference from H_(2)is greatly reduced by optimizing the structure of the CuO/TiO_(2)heterojunction.This reliable detection of carbon monoxide with excellent discrimination against H_(2)is of great significance for the development of CO gas sensors.展开更多
A novel low-temperature SnO_(2) gas sensor was prepared and studied on silicon nanostructures formed by femtosecond laser irradiation.By applying a bias voltage on the silicon substrate to alter the charge distributio...A novel low-temperature SnO_(2) gas sensor was prepared and studied on silicon nanostructures formed by femtosecond laser irradiation.By applying a bias voltage on the silicon substrate to alter the charge distribution on the surface of the SnO_(2),carbon monoxide(CO),and ammonia(NH_(3))gas can be distinguished by the same sensor at room temperature.The experimental results are explained with a mechanism that the sensor works at low temperature because of adsorption of gas molecules that trap electrons to the surface of the SnO_(2).展开更多
SnO_(2)thin-film gas sensors have been successfully fabricated on nanospiked polyurethane polymer surfaces,which are replicated by a low-cost soft nanolithography method from silicon nanospike structures formed with f...SnO_(2)thin-film gas sensors have been successfully fabricated on nanospiked polyurethane polymer surfaces,which are replicated by a low-cost soft nanolithography method from silicon nanospike structures formed with femtosecond laser irradiations.Measurements revealed significant response to carbon monoxide(CO)gas at room temperature,which is considerably different from the sensors of SnO_(2)thin films coated on smooth surfaces that show no response to CO gas at room temperature.The high area/volume ratio and sharp structures of the nanospikes enhance the sensitivity of SnO_(2)at room temperature.This will greatly decrease the electrical power consumption of the gas sensor and the cost for calibrations,and has great potential for application in other sensing systems.展开更多
Oscillatory changes in resistivity of palladium coil based sensors were studied in the presence of carbon monoxide under constant operating current.Oscillations in resistance were observed at operating temperature ran...Oscillatory changes in resistivity of palladium coil based sensors were studied in the presence of carbon monoxide under constant operating current.Oscillations in resistance were observed at operating temperature ranging from 100℃to 130℃.Both the period and the amplitude of the waveform increased with increasing CO concentration.It is believed that oscillations occurred between two branches of a Langmuir-Hinshelwood reaction mechanism.展开更多
The characteristics of the CO gas sensor with partly Nafion solid electrolyte havebeen studied with the method of electrolysis at a fixed potential. It is found that the sensorhas the advantages of rapid response, low...The characteristics of the CO gas sensor with partly Nafion solid electrolyte havebeen studied with the method of electrolysis at a fixed potential. It is found that the sensorhas the advantages of rapid response, low background current and noise etc. in comparisonwith that of the sensor using aqueous electrolyte. Hence, it may also be used for the measurement of low concentration CO gas.展开更多
In this work,the effect of Nafion ionomer content on the structure and catalytic performance of direct CO polymer electrolyte membrane fuel cell(CO-PEMFC)by using Rh-N-C single-atom catalyst as the anode catalyst laye...In this work,the effect of Nafion ionomer content on the structure and catalytic performance of direct CO polymer electrolyte membrane fuel cell(CO-PEMFC)by using Rh-N-C single-atom catalyst as the anode catalyst layers was studied.The ionic plaque and roughness of the anode catalyst layers increase with the increase of Nafion ionomer content.Furthermore,the contact angle measurement results show that the hydrophilicity of the anode catalyst layers also increases with the increase of Nafion ionomer content.However,when the Nafion ionomer content is too low,the binding between microporous layers,catalyst layers and membrane cannot meet the requirement for either electric conductivity or mass transfer.While Nafion ionomer content increased above 30%,the content of water in anode is difficult to control.Therefore,it was found that AN 30(30%Nafion ionomer content of anode)is the best level to effectively extend the three-phase boundary and improve CO-PEMFCs performance.展开更多
基金Supported by the National Natural Science Foundation of China(10 7880 2 33)
文摘The influence of structural design and the parameters of the working electrode on the response time of a solid polymer electrolyte (SPE) carbon monoxide sensor has been studied. Results show that the response time is mainly determined by the RC time constant of the catalyst layer and also related with the working electrode potential.
文摘Carbon monoxide (CO) is a gaseous mediator, which is generated via anenzymatic reaction of heme oxygenase, and it plays physiological roles to regulate cellular respiration and blood flow in the liver. The concentration and distribution of CO molecules in the living body is unknown owing to a lack of a suitable technique for measuring them in vivo. A needle-type CO sensor has been used for bioinstrumentation, but it is inappropriate for implantation in vivo and long-term monitoring. We developed a CO sensor sheet based on hemoglobin (Hb) allostery, as Hb undergoes a conformational change on CO binding. Hb was extracted from mice blood and mixed with agarose gel with a reducer to stabilize deoxy-Hb in the gel. CO-releasing molecules (CORM) were used to mimic CO-generating tissue, and the sensitivity of the Hb gel could be regulated by Hb concentration. We defined the CO–Hb index, an absorbance ratio at 539 and 557 nm, to estimate the accumulation of captured CO in the gel. It correlatively increased with CORM dose, indicating that gel-embedded Hb underwent a conformational change on CO binding, thereby acting as a CO sensor. We subsequently used the Hb-sensor sheet for two-dimensional imaging of CO distribution. CORM-containing gels with different sizes and doses were layered on this sheet. Size- and dose-dependent CO distribution was visualized by scanning the CO-Hb index in the sheet. Our Hb-based CO sensor sheet is composed of biocompatible materials and can be applied to detect low-level CO sources in the living body.
基金supported by the National Natural Science Foundation of China(No.51574054)the University Innovation Team Building Program of Chongqing(No.CXTDX201601030)+2 种基金Scientific and Technological Research Program of Chongqing Municipal Education Commission(No.KJZD-M201901102)Chongqing Science and Technology Bureau(Nos.cstc2017shmsA20017,cstc2018jcyjAX0294,CSTCCXLJRC 201905)the Innovation Leader Project of Chongqing Science and Technology Bureau(No.CSTCCXLJRC201905)。
文摘An optical fiber dual Fabry-Perot interferometric carbon monoxide gas sensor based on PANI/Co3 O4/GO(PCG)sensing membrane coated on the end face of the optical fiber is proposed and fabricated.One end face of photonic crystal fiber(PCF)without cut-off wavelength is fused with a single-mode fiber(SMF),and the other end face of the PCF is coated with PCG sensing membrane.The collapsed layer formed during the air hole fusion of PCF is used as the first reflector,the interface between PCF and sensing membrane is used as the second reflector,and the interface between the sensing membrane and the air is used as the third reflector,thus the dual Fabry-Pe rot structure sensor is formed.The results show that the sensor has excellent sensitivity and selectivity to carbon monoxide.With the increasing concentration of carbon monoxide gas in the range of 0-60 ppm,the intensity of interference spectrum decreases.The sensitivity of the sensor is 0.3473 dB m/ppm,and its linearity is good.The response time and recovery time are 68 s and 106 s,respectively.The sensor has the advantages of the compact size,low cost,high sensitivity,strong selectivity and simple structure.It is suitable for the sensing detection of low concentration carbon monoxide gas.
基金supported by the National Natural Science Foundation of China(Grant Nos.61176066,61101031)Specialized Research Fund for the Doctoral Program of Higher Education(Grant No.20120185110012)
文摘A carbon monoxide gas sensor based on single-walled carbon nanotube （SWCNT） has been developed for detection of carbon monoxide （CO） at room temperature. Copper chloride （CuC1） was mixed with SWNT by mechanical blending. The thin film was deposited on interdigitated electrodes by using airbrush technology. This paper described the fabrication of the sensor for detecting carbon monoxide with concentrations from 20 ppm to 100 ppm. The performance of CO gas sensor was measured by using relevant apparatus to obtain the continuous sensor electric resistance change on exposure to CO and air atmosphere at room temperature, respectively. The results exhibited that the senor presented a larger sensitivity and a good recoverability. The experimental results suggested the potential use of CuC1 doped SWCNT for CO detecting.
基金support from National Natural Science Foundation of China(11874144,12174092,U21A20500)Hubei Provincial Department of Science and Technology(2019CFA079)+1 种基金Wuhan Science and Technology Bureau(2020010601012163)Overseas Expertise Introduction Center for Discipline Innovation(D18025).
文摘The use of heterojunctions is a promising solution to the problem of cross-sensitivity in gas sensors.In this work,a carbon monoxide sensor based on the CuO/TiO_(2)heterojunction was designed and fabricated.Due to the good adsorption properties of CuO materials to CO,and the heterojunction interface charge transfer,the CuO/TiO_(2)thin film sensor exhibits high sensitivity to CO at room temperature.The response is as high as 10.8–200 ppm CO,about 10 times its response to H_(2).Interference from H_(2)is greatly reduced by optimizing the structure of the CuO/TiO_(2)heterojunction.This reliable detection of carbon monoxide with excellent discrimination against H_(2)is of great significance for the development of CO gas sensors.
基金supported by the National Science Foundation under Grant No.[CMMI-1031111].
文摘A novel low-temperature SnO_(2) gas sensor was prepared and studied on silicon nanostructures formed by femtosecond laser irradiation.By applying a bias voltage on the silicon substrate to alter the charge distribution on the surface of the SnO_(2),carbon monoxide(CO),and ammonia(NH_(3))gas can be distinguished by the same sensor at room temperature.The experimental results are explained with a mechanism that the sensor works at low temperature because of adsorption of gas molecules that trap electrons to the surface of the SnO_(2).
基金supported by National Science Foundation under Grant No.1031111.
文摘SnO_(2)thin-film gas sensors have been successfully fabricated on nanospiked polyurethane polymer surfaces,which are replicated by a low-cost soft nanolithography method from silicon nanospike structures formed with femtosecond laser irradiations.Measurements revealed significant response to carbon monoxide(CO)gas at room temperature,which is considerably different from the sensors of SnO_(2)thin films coated on smooth surfaces that show no response to CO gas at room temperature.The high area/volume ratio and sharp structures of the nanospikes enhance the sensitivity of SnO_(2)at room temperature.This will greatly decrease the electrical power consumption of the gas sensor and the cost for calibrations,and has great potential for application in other sensing systems.
文摘Oscillatory changes in resistivity of palladium coil based sensors were studied in the presence of carbon monoxide under constant operating current.Oscillations in resistance were observed at operating temperature ranging from 100℃to 130℃.Both the period and the amplitude of the waveform increased with increasing CO concentration.It is believed that oscillations occurred between two branches of a Langmuir-Hinshelwood reaction mechanism.
文摘The characteristics of the CO gas sensor with partly Nafion solid electrolyte havebeen studied with the method of electrolysis at a fixed potential. It is found that the sensorhas the advantages of rapid response, low background current and noise etc. in comparisonwith that of the sensor using aqueous electrolyte. Hence, it may also be used for the measurement of low concentration CO gas.
基金National Natural Science Foundation of China(Nos.21633008,21875243,21673221 and U1601211)Science and Technology Development Program of Jilin Province,China(Nos.20200201001JC,20190201270JC and 20180101030JC).
文摘In this work,the effect of Nafion ionomer content on the structure and catalytic performance of direct CO polymer electrolyte membrane fuel cell(CO-PEMFC)by using Rh-N-C single-atom catalyst as the anode catalyst layers was studied.The ionic plaque and roughness of the anode catalyst layers increase with the increase of Nafion ionomer content.Furthermore,the contact angle measurement results show that the hydrophilicity of the anode catalyst layers also increases with the increase of Nafion ionomer content.However,when the Nafion ionomer content is too low,the binding between microporous layers,catalyst layers and membrane cannot meet the requirement for either electric conductivity or mass transfer.While Nafion ionomer content increased above 30%,the content of water in anode is difficult to control.Therefore,it was found that AN 30(30%Nafion ionomer content of anode)is the best level to effectively extend the three-phase boundary and improve CO-PEMFCs performance.
