The sulfur-fumigation process not only induces the chemical transformation of Lycium barbarum(Lb,a widely used traditional Chinese medicine)but also severely influences human health.Given the existing challenges like ...The sulfur-fumigation process not only induces the chemical transformation of Lycium barbarum(Lb,a widely used traditional Chinese medicine)but also severely influences human health.Given the existing challenges like the complex and time-consuming operation,as well as the high technical demands of the current detection methods for sulfur-fumed Lycium barbarum(SF-Lb),this paper employs a simple chemiresistor to carry out discrimination research between Lb and SF-Lb which have significant differences in volatolomics.The sensor is constructed by a conductive metal-organic framework(cMOF)thin film,Cu_(3)(HHTP)_(2),due to its abundant active sites,excellent electron transfer performance as well as the capacity to detect specific groups of volatile organic compounds(VOCs).Consequently,the response values of Cu_(3)(HHTP)_(2)-based sensor to 0.5 g SF-Lb(151.74%)are significantly higher than those to normal Lb(80.07%),identifying SF-Lb simply and rapidly with an accuracy of~100%.Our work investigates volatolomics of SF-Lb and establishes a new rapid discrimination method for sulfur-fumed traditional Chinese herbs.展开更多
As one of the famous traditional Chinese herbal medicines,Fritillariae Cirrhosae Bulbus(FCB)is widely used in the prevention and treatment of respiratory diseases and has the best curative effect among the known friti...As one of the famous traditional Chinese herbal medicines,Fritillariae Cirrhosae Bulbus(FCB)is widely used in the prevention and treatment of respiratory diseases and has the best curative effect among the known fritillarias medicines.Due to the variety,complex sources,similar appearance and shape,it is difficult to distinguish FCB with high curative effect(h-FCB)from other common fritillarias(c-FCB)in the market.In this paper,a very simple chemiresistor is used to identify FCB from three commonly used fritillarias drugs.The sensors are fabricated by anisotropic electrically conductive metal-organic framework(cMOF)thin film Cu_(3)(HHTP)_(2)(Cu-HHTP_([001])and Cu-HHTP_([100]))as active materials owing to their ability to detect specific groups of volatile organic compounds(volatolomics)as the functional motifs of chemiresistor.As a result,the sensors show orientation-dependence identification ability to FCB.Cu-HHTP_([001])-based sensor shows the highest response(344.17%)to 0.5 g h-FCB powder volatiles among its three other c-FCB which is much higher than Cu-HHTP_([100])(135.50%).Ultimately,Cu-HHTP_([001])can realize the identification of FCB with an accuracy of 97.2% in a simple and real-time manner.展开更多
Graphene-based gas/vapor sensors have attracted much attention in recent years due to their variety of structures, unique sensing performances, room-temperature working conditions, and tremendous application prospects...Graphene-based gas/vapor sensors have attracted much attention in recent years due to their variety of structures, unique sensing performances, room-temperature working conditions, and tremendous application prospects, etc.Herein, we summarize recent advantages in graphene preparation, sensor construction, and sensing properties of various graphene-based gas/vapor sensors, such as NH_3, NO_2, H_2, CO, SO_2, H_2S, as well as vapor of volatile organic compounds.The detection mechanisms pertaining to various gases are also discussed. In conclusion part, some existing problems which may hinder the sensor applications are presented. Several possible methods to solve these problems are proposed, for example, conceived solutions, hybrid nanostructures, multiple sensor arrays, and new recognition algorithm.展开更多
Bilayer structure with functional overlayer has been commonly adopted to resolve the issue of moisture poisoning in chemiresistors.However,the conventional overlayers always suffer from blocking access of gas molecule...Bilayer structure with functional overlayer has been commonly adopted to resolve the issue of moisture poisoning in chemiresistors.However,the conventional overlayers always suffer from blocking access of gas molecules to sensing layer due to lacking porosity and deteriorated adsorption capability.Herein,taking advantages of the well-defined porous structure and hydrophobic nature of pure silica zeolite,we assembled an overlayer of Pd-PdO clusters-encapsulated mesoporous silicalite-1(MFI)zeolite(named M-S-1)on ZnO sensing layer,to prevent moisture poisoning,and enhance gas diffusion and adsorption capabilities.The inherent capability of MFI zeolite to incorporate monodispersed nanometric(ca.3 nm)Pd-PdO cluster in its void space is of great importance for the NO_(2) adsorption.The Pd-PdO@M-S-1 overlayer can attain negligible moisture interference to the ZnO layer without significantly altering the gas selectivity and baseline resistance,and enhance gas response.Consequently,the Pd-PdO@M-S-1/ZnO bilayer sensor can ultra-selectively(S_(nitrogen dioxide)/S_(interference gas)>4),and ultra-stably detect trace level of NO_(2)(9.5 ppb)at low temperature(370 K)under high levels of humidity(90%RH).This work exemplifies a next-generation solution to design bilayer sensors using zeolite overlayer for eliminating the humidity dependence of the gas-sensing properties.展开更多
We demonstrate the selective detection of hydrogen sulfide at breath concentration levels under humid airflow,using a self-validating 64-channel sensor array based on semiconducting single-walled carbon nanotubes(sc-S...We demonstrate the selective detection of hydrogen sulfide at breath concentration levels under humid airflow,using a self-validating 64-channel sensor array based on semiconducting single-walled carbon nanotubes(sc-SWCNTs).The reproducible sensor fabrication process is based on a multiplexed and controlled dielectrophoretic deposition of sc-SWCNTs.The sensing area is functionalized with gold nanoparticles to address the detection at room temperature by exploiting the affinity between gold and sulfur atoms of the gas.Sensing devices functionalized with an optimized distribution of nanoparticles show a sensitivity of 0.122%/part per billion(ppb)and a calculated limit of detection(LOD)of 3 ppb.Beyond the self-validation,our sensors show increased stability and higher response levels compared to some commercially available electrochemical sensors.The cross-sensitivity to breath gases NH3 and NO is addressed demonstrating the high selectivity to H2S.Finally,mathematical models of sensors’electrical characteristics and sensing responses are developed to enhance the differentiation capabilities of the platform to be used in breath analysis applications.展开更多
Electrospun nanofibers of a polyaniline(PANi)/(+)-camphor-10-sulfonic acid(HCSA)/poly(ethylene oxide)(PEO)composite doped with different variants of graphene oxide(GO)were fabricated and evaluated as chemiresistor gas...Electrospun nanofibers of a polyaniline(PANi)/(+)-camphor-10-sulfonic acid(HCSA)/poly(ethylene oxide)(PEO)composite doped with different variants of graphene oxide(GO)were fabricated and evaluated as chemiresistor gas sensors operating at room temperature.A new strategy for enhancing PANi/PEO gas sensor performance is demonstrated using GO dopants reduced via thermal(trGO)or chemical(crGO)routes.By varying the chemical reduction duration(6 h,crGO-6 or 24 h,crGO-24),tunable enhancement of sensor response was achieved.Upon exposure to short-chain aliphatic alcohol vapors,the partially reduced crGO-6 dopant exhibited higher response than GO and crGO-24,suggesting that the dopant enhances sensor performance via increased electrical conductivity over neat GO,and enhanced hydrogen bonding capability over the further-reduced crGO-24 variant.Sensor arrays consisting of PANi/PEO doped with trGO,crGO-6 or crGO-24 moieties successfully identified methanol,ethanol,and 1-propanol vapors using principal component analysis(PCA).展开更多
基金supported by the National Natural Science Foundation of China(Nos.22205121,22494633,22401281)CAS President's International Fellowship for Visiting Scientists(No.2024VBC0002)+2 种基金the research fund of State Key Laboratory of Mesoscience and Engineering(Nos.MESO-23-A07,MESO-23-T02,MESO-24-A01)First-class Discipline Construction Project(Chemistry)in Higher Education Institutions of Ningxia(Ningxia Normal University)Engineering Research Center of Liupanshan(No.HGZD22-27).
文摘The sulfur-fumigation process not only induces the chemical transformation of Lycium barbarum(Lb,a widely used traditional Chinese medicine)but also severely influences human health.Given the existing challenges like the complex and time-consuming operation,as well as the high technical demands of the current detection methods for sulfur-fumed Lycium barbarum(SF-Lb),this paper employs a simple chemiresistor to carry out discrimination research between Lb and SF-Lb which have significant differences in volatolomics.The sensor is constructed by a conductive metal-organic framework(cMOF)thin film,Cu_(3)(HHTP)_(2),due to its abundant active sites,excellent electron transfer performance as well as the capacity to detect specific groups of volatile organic compounds(VOCs).Consequently,the response values of Cu_(3)(HHTP)_(2)-based sensor to 0.5 g SF-Lb(151.74%)are significantly higher than those to normal Lb(80.07%),identifying SF-Lb simply and rapidly with an accuracy of~100%.Our work investigates volatolomics of SF-Lb and establishes a new rapid discrimination method for sulfur-fumed traditional Chinese herbs.
基金supported by the National Natural Science Foundation of China(No.22205121)Ningxia Autonomous Region Key R&D Program(Special for Talent Introduction)(No.2021BEB04026)+4 种基金Ningxia Natural Science Foundation Project(No.2023AAC03354)the research fund of State Key Laboratory of Mesoscience and Engineering(Nos.MESO-23-A07,MESO-23-T02,MESO-23-T05,MESO-24-A01)Construction of First-Class Disciplines(Pedagogy Discipline)in Ningxia Higher Education Institutions(No.NXYLXK2021B10)First-class Discipline Construction Project(Chemistry)in Higher Education Institutions of Ningxia(Ningxia Normal University)Engineering Research Center of Liupanshan(Nos.HGZD23-15,ZDSYS12).
文摘As one of the famous traditional Chinese herbal medicines,Fritillariae Cirrhosae Bulbus(FCB)is widely used in the prevention and treatment of respiratory diseases and has the best curative effect among the known fritillarias medicines.Due to the variety,complex sources,similar appearance and shape,it is difficult to distinguish FCB with high curative effect(h-FCB)from other common fritillarias(c-FCB)in the market.In this paper,a very simple chemiresistor is used to identify FCB from three commonly used fritillarias drugs.The sensors are fabricated by anisotropic electrically conductive metal-organic framework(cMOF)thin film Cu_(3)(HHTP)_(2)(Cu-HHTP_([001])and Cu-HHTP_([100]))as active materials owing to their ability to detect specific groups of volatile organic compounds(volatolomics)as the functional motifs of chemiresistor.As a result,the sensors show orientation-dependence identification ability to FCB.Cu-HHTP_([001])-based sensor shows the highest response(344.17%)to 0.5 g h-FCB powder volatiles among its three other c-FCB which is much higher than Cu-HHTP_([100])(135.50%).Ultimately,Cu-HHTP_([001])can realize the identification of FCB with an accuracy of 97.2% in a simple and real-time manner.
基金financial supports provided by the National Basic Research Program of China(2013CB932500)the National Natural Science Foundation of China(21171117 and 61574091)+3 种基金the Program for New Century Excellent Talents in University(NCET-12-0356)the Program of Shanghai Academic/Technology Research Leader(15XD1525200)Shanghai Jiao Tong University Agri-X Funding(Agri-X2015007)the Program for Professor of Special Appointment(Eastern Scholar)at Shanghai Institutions of Higher Learning
文摘Graphene-based gas/vapor sensors have attracted much attention in recent years due to their variety of structures, unique sensing performances, room-temperature working conditions, and tremendous application prospects, etc.Herein, we summarize recent advantages in graphene preparation, sensor construction, and sensing properties of various graphene-based gas/vapor sensors, such as NH_3, NO_2, H_2, CO, SO_2, H_2S, as well as vapor of volatile organic compounds.The detection mechanisms pertaining to various gases are also discussed. In conclusion part, some existing problems which may hinder the sensor applications are presented. Several possible methods to solve these problems are proposed, for example, conceived solutions, hybrid nanostructures, multiple sensor arrays, and new recognition algorithm.
基金the financial support by the National Natural Science Foundation of China(Nos.22288101,22375070,and 62303192)the 111 Project of China(No.B17020)Jilin Province Science and Technology Development Plan Project(No.20230508178RC).
文摘Bilayer structure with functional overlayer has been commonly adopted to resolve the issue of moisture poisoning in chemiresistors.However,the conventional overlayers always suffer from blocking access of gas molecules to sensing layer due to lacking porosity and deteriorated adsorption capability.Herein,taking advantages of the well-defined porous structure and hydrophobic nature of pure silica zeolite,we assembled an overlayer of Pd-PdO clusters-encapsulated mesoporous silicalite-1(MFI)zeolite(named M-S-1)on ZnO sensing layer,to prevent moisture poisoning,and enhance gas diffusion and adsorption capabilities.The inherent capability of MFI zeolite to incorporate monodispersed nanometric(ca.3 nm)Pd-PdO cluster in its void space is of great importance for the NO_(2) adsorption.The Pd-PdO@M-S-1 overlayer can attain negligible moisture interference to the ZnO layer without significantly altering the gas selectivity and baseline resistance,and enhance gas response.Consequently,the Pd-PdO@M-S-1/ZnO bilayer sensor can ultra-selectively(S_(nitrogen dioxide)/S_(interference gas)>4),and ultra-stably detect trace level of NO_(2)(9.5 ppb)at low temperature(370 K)under high levels of humidity(90%RH).This work exemplifies a next-generation solution to design bilayer sensors using zeolite overlayer for eliminating the humidity dependence of the gas-sensing properties.
基金the German Federal State of Saxony as part of the“SNIFFBOT:Sniffing Dangerous Gases with Immersive Robots”project under grant agreement number 100369691the German Federal Ministry of Education and Research(No.031B0298)。
文摘We demonstrate the selective detection of hydrogen sulfide at breath concentration levels under humid airflow,using a self-validating 64-channel sensor array based on semiconducting single-walled carbon nanotubes(sc-SWCNTs).The reproducible sensor fabrication process is based on a multiplexed and controlled dielectrophoretic deposition of sc-SWCNTs.The sensing area is functionalized with gold nanoparticles to address the detection at room temperature by exploiting the affinity between gold and sulfur atoms of the gas.Sensing devices functionalized with an optimized distribution of nanoparticles show a sensitivity of 0.122%/part per billion(ppb)and a calculated limit of detection(LOD)of 3 ppb.Beyond the self-validation,our sensors show increased stability and higher response levels compared to some commercially available electrochemical sensors.The cross-sensitivity to breath gases NH3 and NO is addressed demonstrating the high selectivity to H2S.Finally,mathematical models of sensors’electrical characteristics and sensing responses are developed to enhance the differentiation capabilities of the platform to be used in breath analysis applications.
基金The authors would like to acknowledge financial support from United States NSF(CHE-1413449).
文摘Electrospun nanofibers of a polyaniline(PANi)/(+)-camphor-10-sulfonic acid(HCSA)/poly(ethylene oxide)(PEO)composite doped with different variants of graphene oxide(GO)were fabricated and evaluated as chemiresistor gas sensors operating at room temperature.A new strategy for enhancing PANi/PEO gas sensor performance is demonstrated using GO dopants reduced via thermal(trGO)or chemical(crGO)routes.By varying the chemical reduction duration(6 h,crGO-6 or 24 h,crGO-24),tunable enhancement of sensor response was achieved.Upon exposure to short-chain aliphatic alcohol vapors,the partially reduced crGO-6 dopant exhibited higher response than GO and crGO-24,suggesting that the dopant enhances sensor performance via increased electrical conductivity over neat GO,and enhanced hydrogen bonding capability over the further-reduced crGO-24 variant.Sensor arrays consisting of PANi/PEO doped with trGO,crGO-6 or crGO-24 moieties successfully identified methanol,ethanol,and 1-propanol vapors using principal component analysis(PCA).
