A new convenient sulfide electrochemical sensor for marine environmental in situ monitoring and real time survey was developed. The new sensor based on a solid Ag 2S membrane electrode has outstanding chemical sensiti...A new convenient sulfide electrochemical sensor for marine environmental in situ monitoring and real time survey was developed. The new sensor based on a solid Ag 2S membrane electrode has outstanding chemical sensitivity and stability. It responds to the activity of sulfide ions according to a Nernstian slope of -31mV/decade. The sensor can be used to determine the total concentration of sulfides ( C T) by calibrating the pH value of the solution to a standard pH. The practical measurement range for total sulfide concentration is 0.1-10 mg/L in seawater. The sensor has a very low potential drift (<4mV) during two months in 0.1 mg/L sulfide seawater. This paper describes the preparation of the sensitive membrane and some main properties of the sensor.展开更多
Carbon nanotubes CNTs)have been receiving enormous attention in the last decade due to their extraordinary mechanical properties and unique elec- tronic properties.This combination has produced an unprecedented range ...Carbon nanotubes CNTs)have been receiving enormous attention in the last decade due to their extraordinary mechanical properties and unique elec- tronic properties.This combination has produced an unprecedented range of applications for CNTs:elec- tronic,logic and memory chips,chemical and biosen- sots,composites,lithium batteries,gas storage,filters and membranes,etc.This presentation will focus on carbon nanotube based sensors and discuss fabrication, testing and performance.展开更多
Wireless sensor networks have been identified as one of the most important technologies for the 21 st century.Recent advances in micro sensor fabrication technology and wireless communication technology enable the pra...Wireless sensor networks have been identified as one of the most important technologies for the 21 st century.Recent advances in micro sensor fabrication technology and wireless communication technology enable the practical deployment of large-scale,low-power,inexpensive sensor networks.Such an approach offers an advantage over traditional sensing methods in many ways:large-scale,dense deployment not only extends spatial coverage and achieves higher resolution,but also increases the system's fault-tolerance and robustness.Moreover,the ad-hoc nature of wireless sensor networks makes them even more attractive for military and other risk-associated applications,such as environmental observation and habitat monitoring.展开更多
An optical chemical sensor has been developed for the determination of iodine based on the reversible fluorescence quenching of 2, 2, 7, 7, 12, 12, 17, 17-octamethyl-21, 22, 23, 24-tetraoxaquaterene-Li （LiTOE） imm...An optical chemical sensor has been developed for the determination of iodine based on the reversible fluorescence quenching of 2, 2, 7, 7, 12, 12, 17, 17-octamethyl-21, 22, 23, 24-tetraoxaquaterene-Li （LiTOE） immobilized in a plasticized poly（vinyl chloride） （PVC） membrane. The optimum membrane of the sensor consists of 100 mg of PVC, 200 mg of bis （2-ethytbexyl） sebacate （BOS） and 3.0 mg of LiTOE. The maximum response of the optode membrane for iodine is obtained in Tris-HCl buffer solutlon （pH 8.0）. With the optimum conditions described, the proposed sensor responds linearly in the measuring range of 3.90×10^-2 to 3.90×10^-4 mol/L, and has a detection limit of 6.0×10^-8 mol/L. The response time of the sensor is less than I rain. In addition to high reproducibility and reversibility of the fluorescence signal, the sensor also exhibits good selectivity. It is not interfered by some common anions and cations. It is applied for the determination of iodine in table salt samples. The results agree with those obtained by another method.展开更多
As the hydrazine is toxic, the methods to detect hydrazine at low concentrations are essential in scientific research. This preliminary study reported on how to increase the efficiency of ZnO/reduced graphene oxide (r...As the hydrazine is toxic, the methods to detect hydrazine at low concentrations are essential in scientific research. This preliminary study reported on how to increase the efficiency of ZnO/reduced graphene oxide (rGO) by adding durian peel ash (DPA) and using three-electrode method. The ZnO/rGO composites were prepared using chemical reaction of graphene oxide (GO) with zinc chloride. The rGO was prepared by the chemical reduction of GO using hydrazine. The properties of the samples were investigated using scanning electron microscopy, atomic force microscopy, X-ray diffraction, and Potentiostat/Galvanostat. The results showed that the optimal condition for the composite material was 70%DPA:30%ZnO/rGO with the sensitivity of 222.92 mA/mM<span style="white-space:nowrap;">·</span>cm<sup>2</sup> and the current density up to 116.50 ± 0.95 A/g. The relationship between the current and the hydrazine concentration was I (μA) = 48.69 + 21.91C (mM) with R<sup>2</sup> of 0.9870. The minimum concentration of hydrazine solution that the modified electrode can measure was 0.125 mM. The DPA powder can then be used to enhance the hydrazine detection efficiency at low concentrations.展开更多
Real-time health monitoring and ongoing evaluation of physiological conditions are becoming increasingly vital for the advancement of future medical diagnostics and personalized healthcare solutions.Given that certain...Real-time health monitoring and ongoing evaluation of physiological conditions are becoming increasingly vital for the advancement of future medical diagnostics and personalized healthcare solutions.Given that certain illnesses necessitate prompt and accessible detection methods,wearable chemical sensors have garnered considerable interest for their capability to monitor health through physiological signals and chemical indicators.This review delivers a thorough examination of recent developments in four primary categories of wearable chemical sensors:biosensors,humidity sensors,gas sensors,and ion sensors.We explore the representative materials,device structures,operating mechanisms,and various application scenarios for each type of sensor.By investigating the latest innovations in these technologies,we aim to provide a detailed overview of the current research landscape,highlight existing challenges,and present potential future directions of wearable chemical sensors in healthcare monitoring.展开更多
The ever-increasing need to determine and monitor the chemical constituents of the constantly evolving environment has led the global scientific community to invest considerable research effort in the development of e...The ever-increasing need to determine and monitor the chemical constituents of the constantly evolving environment has led the global scientific community to invest considerable research effort in the development of efficient and user-friendly chemical sensors.The development of improved chemical sensors largely depends on the synthesis of novel materials with the ability to transform a molecular recognition event into a readable signal.Among the various types of sensory materials,those where analyte detection is based on the change of a luminescence signal are gaining increasing attention due to the extremely high sensitivities which can be achieved in combination with new technological advances enabling the integration of optical detection systems in small,portable and easy to use devices.In this critical review we approach the emerging field of sensory materials based on luminescent metal–organic frameworks(LMOFs)by beginning with a survey of the general principles of luminescence-based sensing.In particular,after a brief overview,we first focus on the working principles and successes of well established sensory materials based on small molecules and conjugated polymers.Subsequently,we concentrate on the special features of LMOFs which make them promising sensory materials and we discuss best practices which researchers in the field should follow in order to prove the sensing ability of LMOFs and avoid common misconceptions and errors.We continue with presenting selected examples of LMOF-based sensors for nitroaromatics,humidity and heavy metal ions from the recent literature and we conclude with a summary of the state-of-the-art of LMOF sensors.Finally,we propose some directions for future research on LMOF sensors.展开更多
Optical fiber sensors have gained significant attention in recent years owing to their remarkable advantages of remote operation and rapid response.The integration of optical fiber sensing with the microfluidics techn...Optical fiber sensors have gained significant attention in recent years owing to their remarkable advantages of remote operation and rapid response.The integration of optical fiber sensing with the microfluidics technology has paved the way for the establishment of optical fiber optofluidic sensing.Optical fiber optofluidic systems possess the advantages of the low invasiveness,compact structure,excellent biocompatibility,and the ability to handle small analyte volumes,rendering them particularly suitable for serving as chemical sensors and biosensors.In this paper,we present an in-depth overview of optical fiber optofluidic chemical sensors and biosensors.Firstly,we provide a comprehensive summary of the types of optical fibers commonly employed in optofluidic chemical and biosensing,elucidating their distinct attributes and performance characteristics.Subsequently,we introduce and thoroughly analyze several representative sensing mechanisms employed in optical fiber optofluidic systems and main performance parameters.Furthermore,this review delves into the modification and functionalization of optical fibers.Additionally,we showcase typical biosensing and chemical sensing applications to demonstrate the practicality and versatility of optical fiber optofluidic sensing.Finally,the conclusion and outlook are given.展开更多
The next generation of electronics technology is purely going to be based on wearable sensing systems. Wearable electronic sensors that can operate in a continuous and sustainable manner without the need of an externa...The next generation of electronics technology is purely going to be based on wearable sensing systems. Wearable electronic sensors that can operate in a continuous and sustainable manner without the need of an external power sources, are essential for portable and mobile electronic applications. In this review article, the recent progress and advantages of wearable self-powered smart chemical sensors systems for wearable electronics are presented. An overview of various modes of energy conversion and storage technologies for self-powered devices is provided. Self-powered chemical sensors (SPCS) systems with integrated energy units are then discussed, separated as solar cell-based SPCS, triboelectric nano-generators based SPCS, piezoelectric nano-generators based SPCS, energy storage device based SPCS, and thermal energy-based SPCS. Finally, the outlook on future prospects of wearable chemical sensors in self-powered sensing systems is addressed.展开更多
Organic field-effect transistors（OFETs） offer great potential applications in chemical and biological sensing for homeland security,environmental monitoring,industry manufacturing,and medical/biological detection. M...Organic field-effect transistors（OFETs） offer great potential applications in chemical and biological sensing for homeland security,environmental monitoring,industry manufacturing,and medical/biological detection. Many studies concentrate on sensitivity and selectivity improvement of OFET-based sensors. We report four organic semiconductors with different alkyl side chain lengths but the same π-conjugated core structure for OFETs. Our work focuses on the molecular structure of organic semiconductors（OSCs）. Alkyl side chains can hinder the diffusion of ammonia into the OSCs layer,which blocks the interaction between ammonia and conducting channel. The result also reveals the relationship between the alky chain and the film thickness in sensitivity control. These results are expected to be a guide to the molecular design of organic semiconductors and the choice of OSCs.展开更多
Chemical sensor arrays can obtain more comprehensive analyte information through high-dimensional data.It is of great significance in the analysis of multi-component complex samples.This review summarizes the developm...Chemical sensor arrays can obtain more comprehensive analyte information through high-dimensional data.It is of great significance in the analysis of multi-component complex samples.This review summarizes the development and status of chemical sensor arrays.We focused on the design of chemical sensor arrays based on various sensing materials.In addition,several pattern recognition methods in chemometrics are introduced.And applications of chemical sensor arrays in food monitoring,medical diagnosis,and environmental monitoring are illustrated.Based on the analysis of the limitations of current sensor array technology,the direction of the array is also predicted.This review aims to help the broad readership understand the research state of chemical sensor arrays and their development prospects.展开更多
A novel electrochemical oxygen sensor has been developed by using La beta -Al2O3 as solid electrolyte and Cr+Cr2O3 as reference electrode. The sensor not only can be used as normal oxygen sensor but also as an ultra-l...A novel electrochemical oxygen sensor has been developed by using La beta -Al2O3 as solid electrolyte and Cr+Cr2O3 as reference electrode. The sensor not only can be used as normal oxygen sensor but also as an ultra-low oxygen sensor. Especially, it is very sensitive to measure ultra-low oxygen in molten metal. For estimating the accuracy of La beta -Al2O3 oxygen sensor, two series of oxygen activities in molten iron at different oxygen contents and different temperature were measured by both La beta -Al2O3 oxygen sensor and ZrO2 oxygen sensor. The theoretical values of oxygen activities in molten iron (3.30%C, in mass fraction) at 1723K and 1745K were also evaluated for comparing the measuring results of two sensors. At last, the error of measurement for La beta -Al2O3 oxygen sensor was discussed too.展开更多
1 Introduction Gas sensors have been used in a range of applications where they play a crucial role in ensuring that we live safely and comfortablely.Gas safety products,such as gas detectors/alarms,especially those e...1 Introduction Gas sensors have been used in a range of applications where they play a crucial role in ensuring that we live safely and comfortablely.Gas safety products,such as gas detectors/alarms,especially those equipped with combustible gas,toxic gas,or oxygen sensors,are one of the most important applications for gas sensors.The purpose of gas detector/alarm units is展开更多
A novel chemiluminescence(CL) sensor, which can be used for hydroxylamine determination in combination with flow injection analysis, was developed by electrostatically immobilizing luminol and periodate on anion exch...A novel chemiluminescence(CL) sensor, which can be used for hydroxylamine determination in combination with flow injection analysis, was developed by electrostatically immobilizing luminol and periodate on anion exchange resin respectively. Hydroxylamine was sensed by its enhancing effect on the weak CL reaction between luminol and periodate, which were eluted from the ion exchange column. The response of the sensor to hydroxylamine was linear in the concentration range of 8.0×10^(-8)-2.0×10^(-6)mol/L with a detection limit of 4.0×10^(-8)mol/L hydroxylamine(3σ).The relative standard deviation(RSD) was 2.0% for 9 repetitive determinations at a hydroxylamine concentration of 5.0×10^(-7) mol/L. The sensor could be reused for over 400 times with a good reproducibility and was used to determine hydroxylamine in wastewater.展开更多
This work reports an FTIR study of the NO_x adsorption/desorption cycles on tin oxide nanosized particles under the operating conditions of real sensors (150℃,in presence of O_2).The chemical reactions are monitored...This work reports an FTIR study of the NO_x adsorption/desorption cycles on tin oxide nanosized particles under the operating conditions of real sensors (150℃,in presence of O_2).The chemical reactions are monitored in situ and correlated with the variations of the SnO_2 electrical conductivity.On the basis of the FTIR spectra,two contributing mechanisms for the NO_x detection are suggested.The first one presents the formation of bridged nitrate groups bound to the SnO_2 surface via oxygen vacancies acting as electron donor sites.The second mechanism also involves surface oxygen vacancies in the coordination of NO_x,but this time the formation of NO_x anionic species is considered.Both mechanisms lead to the decrease of the electrical conductivity under NO_x adsorption.However,the bridged nitrate groups are not reversible under gas desorption and thus irreversibly contaminate the surface after the first NO_x adsorption.On the contrary,the nitrosyl anionic species are reversible and,from the second NO_x adsorption/desorption cycle,ensure the reproducibility of the sensor response.展开更多
Intelligent chemical sensors have been extensively used in food safety and environmental assessment,while limited sensitivity and homogeneity bring about huge obstacles to their practical application.Herein,novel ioni...Intelligent chemical sensors have been extensively used in food safety and environmental assessment,while limited sensitivity and homogeneity bring about huge obstacles to their practical application.Herein,novel ionically conductive sensitive materials were elaborately designed based on metal ion decorated graphene oxide(GO)via a facile and general in-situ spin-coating strategy,where the abundant functional groups(-OH and-COOH)of GO layer could provide natural binding sites for various bivalent metal cations(such as Cu^(2+),Ni^(2+),Zn^(2+),Co^(2+),and Mg^(2+))through coordination and electrostatic inter-action.The intercalated metal cations on the layered GO nanosheets can be regarded as charge carriers and complexation with targeted gas(cadaverine,Cad),which is a typical metabolites production and food degradants.By contrast,the designed GO@Cu(Ⅱ)sensor exhibited the optimal sensing performance toward Cad molecules at room temperature,including ultra-low detection limit(ca.3 nL),excellent sensitivity,and rapid low concentration detection rate(only 16 s).Interestingly,the sensor exhibited an irreversible and specific response toward Cad,while it showed a transient and reversible response to other interfering gases,implying its outstanding selectivity.In addition,the GO@Cu(Ⅱ)sensor enabled real-time monitoring of the decay progression of cheese,and it exhibited great potential for large-scale production via its excellent homogeneity.It provides an efficient approach to tailoring intelligent chemical sensors for real-time food safety monitoring and human health warning.展开更多
A novel electrogenerated chemiluminescence(ECL)sensor for the determination of metoclopramide was developed by employing ruthenium complex as an ECL signal producer and an ordered mesoporous carbon(OMC)material as mod...A novel electrogenerated chemiluminescence(ECL)sensor for the determination of metoclopramide was developed by employing ruthenium complex as an ECL signal producer and an ordered mesoporous carbon(OMC)material as modified material.The ECL sensor was fabricated by adsorption ruthenium complex into a mixture of OMC and Nafion,which showed good electrochemical and ECL behaviors.It was found that the ECL intensity of the sensor fabricated was greatly enhanced in the presence of metoclopramide.Based on this finding,a highly sensitive and reproducible ECL method was developed for the determination of metoclopramide.The result showed that the ECL intensity was linear with the concentration of metoclopramide in the range from 1.0×10-10 to 5.0×10-7M and the detection limit was 3×10-11M.The ECL sensor exhibited a long-term stability and a fine reproducibility with relative standard deviation of 1.0%for 1.0×10-10M metoclopramide in 18 continuous determinations.The developed method has been applied to the determination of metoclopramide in tablet samples with satisfactory results.展开更多
In the last decade, microelectromechanical systems(MEMS) SU-8 polymeric cantilevers with piezoresistive readout combined with the advances in molecular recognition techniques have found versatile applications,especial...In the last decade, microelectromechanical systems(MEMS) SU-8 polymeric cantilevers with piezoresistive readout combined with the advances in molecular recognition techniques have found versatile applications,especially in the field of chemical and biological sensing.Compared to conventional solid-state semiconductor-based piezoresistive cantilever sensors, SU-8 polymeric cantilevers have advantages in terms of better sensitivity along with reduced material and fabrication cost. In recent times,numerous researchers have investigated their potential as a sensing platform due to high performance-to-cost ratio of SU-8 polymer-based cantilever sensors. In this article, we critically review the design, fabrication, and performance aspects of surface stress-based piezoresistive SU-8 polymeric cantilever sensors. The evolution of surface stress-based piezoresistive cantilever sensors from solid-state semiconductor materials to polymers, especially SU-8 polymer, is discussed in detail. Theoretical principles of surface stress generation and their application in cantilever sensing technology are also devised. Variants of SU-8 polymeric cantilevers with different composition of materials in cantilever stacks are explained. Furthermore, the interdependence of the material selection, geometrical design parameters, and fabrication process of piezoresistive SU-8 polymeric cantilever sensors and their cumulative impact on the sensor response are also explained in detail.In addition to the design-, fabrication-, and performancerelated factors, this article also describes various challenges in engineering SU-8 polymeric cantilevers as a universal sensing platform such as temperature and moisture vulnerability. This review article would serve as a guideline for researchers to understand specifics and functionality of surface stress-based piezoresistive SU-8 cantilever sensors.展开更多
Here,we demonstrate the assembly of a new stable lanthanide-based metal-organic framework(MOF),Eu(HDPB)(phen)(1)(HDPB=(1,1’:3’,1’’-terphenyl)-3,3’’,5,5’’-tetracarboxylic acid,phen=1,10-phenanthroline),with a t...Here,we demonstrate the assembly of a new stable lanthanide-based metal-organic framework(MOF),Eu(HDPB)(phen)(1)(HDPB=(1,1’:3’,1’’-terphenyl)-3,3’’,5,5’’-tetracarboxylic acid,phen=1,10-phenanthroline),with a three-dimensional framework under solvothermal conditions.1 showed strong red fluorescence emission at room temperature and could be used as a selective and sensitive chemical sensor for pH and folic acid(FA)detection.Moreover,1 could also be applied as a fluorescent material for the visible identification of fingerprints.Then,using 1 as a filler,two mixed-matrix membranes(MMMs),1@poly(ε-caprolactone)(PCL)and 1@poly(vinylidene difluoride)(PVDF),have been fabricated.Notably,owing to the hydrophobic protection provided by the polymer matrix of the MOF particles,these two MMMs also exhibited fluorescence emission comparable to that of 1 and could be used for FA sensing with good selectivity and remarkable recyclability.More importantly,this is the first time that Eu-MOF-based MMMs have been employed in FA detection.The fabrication of MOF-based MMMs not only provides a facile method for sensing biomarkers,but it also enhances the recyclability of sensors.展开更多
文摘A new convenient sulfide electrochemical sensor for marine environmental in situ monitoring and real time survey was developed. The new sensor based on a solid Ag 2S membrane electrode has outstanding chemical sensitivity and stability. It responds to the activity of sulfide ions according to a Nernstian slope of -31mV/decade. The sensor can be used to determine the total concentration of sulfides ( C T) by calibrating the pH value of the solution to a standard pH. The practical measurement range for total sulfide concentration is 0.1-10 mg/L in seawater. The sensor has a very low potential drift (<4mV) during two months in 0.1 mg/L sulfide seawater. This paper describes the preparation of the sensitive membrane and some main properties of the sensor.
文摘Carbon nanotubes CNTs)have been receiving enormous attention in the last decade due to their extraordinary mechanical properties and unique elec- tronic properties.This combination has produced an unprecedented range of applications for CNTs:elec- tronic,logic and memory chips,chemical and biosen- sots,composites,lithium batteries,gas storage,filters and membranes,etc.This presentation will focus on carbon nanotube based sensors and discuss fabrication, testing and performance.
文摘Wireless sensor networks have been identified as one of the most important technologies for the 21 st century.Recent advances in micro sensor fabrication technology and wireless communication technology enable the practical deployment of large-scale,low-power,inexpensive sensor networks.Such an approach offers an advantage over traditional sensing methods in many ways:large-scale,dense deployment not only extends spatial coverage and achieves higher resolution,but also increases the system's fault-tolerance and robustness.Moreover,the ad-hoc nature of wireless sensor networks makes them even more attractive for military and other risk-associated applications,such as environmental observation and habitat monitoring.
文摘An optical chemical sensor has been developed for the determination of iodine based on the reversible fluorescence quenching of 2, 2, 7, 7, 12, 12, 17, 17-octamethyl-21, 22, 23, 24-tetraoxaquaterene-Li （LiTOE） immobilized in a plasticized poly（vinyl chloride） （PVC） membrane. The optimum membrane of the sensor consists of 100 mg of PVC, 200 mg of bis （2-ethytbexyl） sebacate （BOS） and 3.0 mg of LiTOE. The maximum response of the optode membrane for iodine is obtained in Tris-HCl buffer solutlon （pH 8.0）. With the optimum conditions described, the proposed sensor responds linearly in the measuring range of 3.90×10^-2 to 3.90×10^-4 mol/L, and has a detection limit of 6.0×10^-8 mol/L. The response time of the sensor is less than I rain. In addition to high reproducibility and reversibility of the fluorescence signal, the sensor also exhibits good selectivity. It is not interfered by some common anions and cations. It is applied for the determination of iodine in table salt samples. The results agree with those obtained by another method.
文摘As the hydrazine is toxic, the methods to detect hydrazine at low concentrations are essential in scientific research. This preliminary study reported on how to increase the efficiency of ZnO/reduced graphene oxide (rGO) by adding durian peel ash (DPA) and using three-electrode method. The ZnO/rGO composites were prepared using chemical reaction of graphene oxide (GO) with zinc chloride. The rGO was prepared by the chemical reduction of GO using hydrazine. The properties of the samples were investigated using scanning electron microscopy, atomic force microscopy, X-ray diffraction, and Potentiostat/Galvanostat. The results showed that the optimal condition for the composite material was 70%DPA:30%ZnO/rGO with the sensitivity of 222.92 mA/mM<span style="white-space:nowrap;">·</span>cm<sup>2</sup> and the current density up to 116.50 ± 0.95 A/g. The relationship between the current and the hydrazine concentration was I (μA) = 48.69 + 21.91C (mM) with R<sup>2</sup> of 0.9870. The minimum concentration of hydrazine solution that the modified electrode can measure was 0.125 mM. The DPA powder can then be used to enhance the hydrazine detection efficiency at low concentrations.
基金supported by the Shandong Excellent Young Scientists Fund Program(Overseas)(2023HWYQ-035)the Taishan Scholar Program of Shandong Province(tsqn202306078)+2 种基金the Guangdong Basic and Applied Basic Research Foundation(2024A1515011635)the Natural Science Foundation of Shandong Province(ZR2023MF108)the Jinan Central Hospital(1190022050)。
文摘Real-time health monitoring and ongoing evaluation of physiological conditions are becoming increasingly vital for the advancement of future medical diagnostics and personalized healthcare solutions.Given that certain illnesses necessitate prompt and accessible detection methods,wearable chemical sensors have garnered considerable interest for their capability to monitor health through physiological signals and chemical indicators.This review delivers a thorough examination of recent developments in four primary categories of wearable chemical sensors:biosensors,humidity sensors,gas sensors,and ion sensors.We explore the representative materials,device structures,operating mechanisms,and various application scenarios for each type of sensor.By investigating the latest innovations in these technologies,we aim to provide a detailed overview of the current research landscape,highlight existing challenges,and present potential future directions of wearable chemical sensors in healthcare monitoring.
文摘The ever-increasing need to determine and monitor the chemical constituents of the constantly evolving environment has led the global scientific community to invest considerable research effort in the development of efficient and user-friendly chemical sensors.The development of improved chemical sensors largely depends on the synthesis of novel materials with the ability to transform a molecular recognition event into a readable signal.Among the various types of sensory materials,those where analyte detection is based on the change of a luminescence signal are gaining increasing attention due to the extremely high sensitivities which can be achieved in combination with new technological advances enabling the integration of optical detection systems in small,portable and easy to use devices.In this critical review we approach the emerging field of sensory materials based on luminescent metal–organic frameworks(LMOFs)by beginning with a survey of the general principles of luminescence-based sensing.In particular,after a brief overview,we first focus on the working principles and successes of well established sensory materials based on small molecules and conjugated polymers.Subsequently,we concentrate on the special features of LMOFs which make them promising sensory materials and we discuss best practices which researchers in the field should follow in order to prove the sensing ability of LMOFs and avoid common misconceptions and errors.We continue with presenting selected examples of LMOF-based sensors for nitroaromatics,humidity and heavy metal ions from the recent literature and we conclude with a summary of the state-of-the-art of LMOF sensors.Finally,we propose some directions for future research on LMOF sensors.
基金supported by the Heilongjiang Provincial Natural Science Foundation of China(Grant No.LH2021F019)Fundamental Research Funds for the Central Universities,China(Grant No.3072022CF2506)National Natural Science Foundation of China(Grant Nos.62305082,11574061,and 62065001).
文摘Optical fiber sensors have gained significant attention in recent years owing to their remarkable advantages of remote operation and rapid response.The integration of optical fiber sensing with the microfluidics technology has paved the way for the establishment of optical fiber optofluidic sensing.Optical fiber optofluidic systems possess the advantages of the low invasiveness,compact structure,excellent biocompatibility,and the ability to handle small analyte volumes,rendering them particularly suitable for serving as chemical sensors and biosensors.In this paper,we present an in-depth overview of optical fiber optofluidic chemical sensors and biosensors.Firstly,we provide a comprehensive summary of the types of optical fibers commonly employed in optofluidic chemical and biosensing,elucidating their distinct attributes and performance characteristics.Subsequently,we introduce and thoroughly analyze several representative sensing mechanisms employed in optical fiber optofluidic systems and main performance parameters.Furthermore,this review delves into the modification and functionalization of optical fibers.Additionally,we showcase typical biosensing and chemical sensing applications to demonstrate the practicality and versatility of optical fiber optofluidic sensing.Finally,the conclusion and outlook are given.
基金This work has been supported by the Ministry of Human Resource Development(MHRD),India,through a Centre of Excellence grant(CENEMA,RP-074)also by the Department of Science and Technology(DST),India via grant no.DST-MES(RP-155)+2 种基金Part of this work has been carried out with financial support from the National Aluminum Company Limited(NALCO)via grant no.RP-199.C.S.R.acknowledges Department of Science and Technology(DST)-SERB Early Career Research project(No.ECR/2017/001850)DST-Nanomission(DST/NM/NT/2019/205(G))‘Karnataka Science and Technology Promotion Society(KSTePS/VGST-RGS-F/2018-19/GRD No.829/315)S.S.acknowledges the DST-SERB for a National Post-Doctoral Fellowship(No.PDF/2020/000620).
文摘The next generation of electronics technology is purely going to be based on wearable sensing systems. Wearable electronic sensors that can operate in a continuous and sustainable manner without the need of an external power sources, are essential for portable and mobile electronic applications. In this review article, the recent progress and advantages of wearable self-powered smart chemical sensors systems for wearable electronics are presented. An overview of various modes of energy conversion and storage technologies for self-powered devices is provided. Self-powered chemical sensors (SPCS) systems with integrated energy units are then discussed, separated as solar cell-based SPCS, triboelectric nano-generators based SPCS, piezoelectric nano-generators based SPCS, energy storage device based SPCS, and thermal energy-based SPCS. Finally, the outlook on future prospects of wearable chemical sensors in self-powered sensing systems is addressed.
基金financially supported by the National Natural Science Foundation of China(21302142 and 51603151)the National Key Research and Development Program of China(2017YFA0103900 and 2017YFA0103904)+1 种基金the 1000 Youth Talent Planthe Fundamental Research Funds for the Central Universities of China
文摘Organic field-effect transistors（OFETs） offer great potential applications in chemical and biological sensing for homeland security,environmental monitoring,industry manufacturing,and medical/biological detection. Many studies concentrate on sensitivity and selectivity improvement of OFET-based sensors. We report four organic semiconductors with different alkyl side chain lengths but the same π-conjugated core structure for OFETs. Our work focuses on the molecular structure of organic semiconductors（OSCs）. Alkyl side chains can hinder the diffusion of ammonia into the OSCs layer,which blocks the interaction between ammonia and conducting channel. The result also reveals the relationship between the alky chain and the film thickness in sensitivity control. These results are expected to be a guide to the molecular design of organic semiconductors and the choice of OSCs.
基金funded by Natural Science Foundation of Heilongjiang Province(No.LH2022B004)Fundamental Research Funds for the Central Universities(No.2572022DJ01)+1 种基金111 Project(No.B20088)Heilongjiang Touyan Innovation Team Program(Tree Genetics and Breeding Innovation Team)。
文摘Chemical sensor arrays can obtain more comprehensive analyte information through high-dimensional data.It is of great significance in the analysis of multi-component complex samples.This review summarizes the development and status of chemical sensor arrays.We focused on the design of chemical sensor arrays based on various sensing materials.In addition,several pattern recognition methods in chemometrics are introduced.And applications of chemical sensor arrays in food monitoring,medical diagnosis,and environmental monitoring are illustrated.Based on the analysis of the limitations of current sensor array technology,the direction of the array is also predicted.This review aims to help the broad readership understand the research state of chemical sensor arrays and their development prospects.
基金supported by National Natural Science Foundation of China under grant No.59374160.
文摘A novel electrochemical oxygen sensor has been developed by using La beta -Al2O3 as solid electrolyte and Cr+Cr2O3 as reference electrode. The sensor not only can be used as normal oxygen sensor but also as an ultra-low oxygen sensor. Especially, it is very sensitive to measure ultra-low oxygen in molten metal. For estimating the accuracy of La beta -Al2O3 oxygen sensor, two series of oxygen activities in molten iron at different oxygen contents and different temperature were measured by both La beta -Al2O3 oxygen sensor and ZrO2 oxygen sensor. The theoretical values of oxygen activities in molten iron (3.30%C, in mass fraction) at 1723K and 1745K were also evaluated for comparing the measuring results of two sensors. At last, the error of measurement for La beta -Al2O3 oxygen sensor was discussed too.
文摘1 Introduction Gas sensors have been used in a range of applications where they play a crucial role in ensuring that we live safely and comfortablely.Gas safety products,such as gas detectors/alarms,especially those equipped with combustible gas,toxic gas,or oxygen sensors,are one of the most important applications for gas sensors.The purpose of gas detector/alarm units is
基金Supported by the National Natural Science Foundation of China(No.2 9975 0 13,9835 110 )
文摘A novel chemiluminescence(CL) sensor, which can be used for hydroxylamine determination in combination with flow injection analysis, was developed by electrostatically immobilizing luminol and periodate on anion exchange resin respectively. Hydroxylamine was sensed by its enhancing effect on the weak CL reaction between luminol and periodate, which were eluted from the ion exchange column. The response of the sensor to hydroxylamine was linear in the concentration range of 8.0×10^(-8)-2.0×10^(-6)mol/L with a detection limit of 4.0×10^(-8)mol/L hydroxylamine(3σ).The relative standard deviation(RSD) was 2.0% for 9 repetitive determinations at a hydroxylamine concentration of 5.0×10^(-7) mol/L. The sensor could be reused for over 400 times with a good reproducibility and was used to determine hydroxylamine in wastewater.
文摘This work reports an FTIR study of the NO_x adsorption/desorption cycles on tin oxide nanosized particles under the operating conditions of real sensors (150℃,in presence of O_2).The chemical reactions are monitored in situ and correlated with the variations of the SnO_2 electrical conductivity.On the basis of the FTIR spectra,two contributing mechanisms for the NO_x detection are suggested.The first one presents the formation of bridged nitrate groups bound to the SnO_2 surface via oxygen vacancies acting as electron donor sites.The second mechanism also involves surface oxygen vacancies in the coordination of NO_x,but this time the formation of NO_x anionic species is considered.Both mechanisms lead to the decrease of the electrical conductivity under NO_x adsorption.However,the bridged nitrate groups are not reversible under gas desorption and thus irreversibly contaminate the surface after the first NO_x adsorption.On the contrary,the nitrosyl anionic species are reversible and,from the second NO_x adsorption/desorption cycle,ensure the reproducibility of the sensor response.
基金supported by the National Natural Science Foundation of China(Nos.62074111,22105043)the Science&Technology Foundation of Shanghai(Nos.19JC1412402,20JC1415600)+2 种基金Shanghai Municipal Science and Technology Major Project(No.2021SHZDZX0100)Shanghai Municipal Commission of Science and Technology Project(No.19511132101)the support of the Fundamental Research Funds for the Central Universities
文摘Intelligent chemical sensors have been extensively used in food safety and environmental assessment,while limited sensitivity and homogeneity bring about huge obstacles to their practical application.Herein,novel ionically conductive sensitive materials were elaborately designed based on metal ion decorated graphene oxide(GO)via a facile and general in-situ spin-coating strategy,where the abundant functional groups(-OH and-COOH)of GO layer could provide natural binding sites for various bivalent metal cations(such as Cu^(2+),Ni^(2+),Zn^(2+),Co^(2+),and Mg^(2+))through coordination and electrostatic inter-action.The intercalated metal cations on the layered GO nanosheets can be regarded as charge carriers and complexation with targeted gas(cadaverine,Cad),which is a typical metabolites production and food degradants.By contrast,the designed GO@Cu(Ⅱ)sensor exhibited the optimal sensing performance toward Cad molecules at room temperature,including ultra-low detection limit(ca.3 nL),excellent sensitivity,and rapid low concentration detection rate(only 16 s).Interestingly,the sensor exhibited an irreversible and specific response toward Cad,while it showed a transient and reversible response to other interfering gases,implying its outstanding selectivity.In addition,the GO@Cu(Ⅱ)sensor enabled real-time monitoring of the decay progression of cheese,and it exhibited great potential for large-scale production via its excellent homogeneity.It provides an efficient approach to tailoring intelligent chemical sensors for real-time food safety monitoring and human health warning.
基金supported by the National Natural Science Foundation of China(No.20805028)
文摘A novel electrogenerated chemiluminescence(ECL)sensor for the determination of metoclopramide was developed by employing ruthenium complex as an ECL signal producer and an ordered mesoporous carbon(OMC)material as modified material.The ECL sensor was fabricated by adsorption ruthenium complex into a mixture of OMC and Nafion,which showed good electrochemical and ECL behaviors.It was found that the ECL intensity of the sensor fabricated was greatly enhanced in the presence of metoclopramide.Based on this finding,a highly sensitive and reproducible ECL method was developed for the determination of metoclopramide.The result showed that the ECL intensity was linear with the concentration of metoclopramide in the range from 1.0×10-10 to 5.0×10-7M and the detection limit was 3×10-11M.The ECL sensor exhibited a long-term stability and a fine reproducibility with relative standard deviation of 1.0%for 1.0×10-10M metoclopramide in 18 continuous determinations.The developed method has been applied to the determination of metoclopramide in tablet samples with satisfactory results.
文摘In the last decade, microelectromechanical systems(MEMS) SU-8 polymeric cantilevers with piezoresistive readout combined with the advances in molecular recognition techniques have found versatile applications,especially in the field of chemical and biological sensing.Compared to conventional solid-state semiconductor-based piezoresistive cantilever sensors, SU-8 polymeric cantilevers have advantages in terms of better sensitivity along with reduced material and fabrication cost. In recent times,numerous researchers have investigated their potential as a sensing platform due to high performance-to-cost ratio of SU-8 polymer-based cantilever sensors. In this article, we critically review the design, fabrication, and performance aspects of surface stress-based piezoresistive SU-8 polymeric cantilever sensors. The evolution of surface stress-based piezoresistive cantilever sensors from solid-state semiconductor materials to polymers, especially SU-8 polymer, is discussed in detail. Theoretical principles of surface stress generation and their application in cantilever sensing technology are also devised. Variants of SU-8 polymeric cantilevers with different composition of materials in cantilever stacks are explained. Furthermore, the interdependence of the material selection, geometrical design parameters, and fabrication process of piezoresistive SU-8 polymeric cantilever sensors and their cumulative impact on the sensor response are also explained in detail.In addition to the design-, fabrication-, and performancerelated factors, this article also describes various challenges in engineering SU-8 polymeric cantilevers as a universal sensing platform such as temperature and moisture vulnerability. This review article would serve as a guideline for researchers to understand specifics and functionality of surface stress-based piezoresistive SU-8 cantilever sensors.
基金the National Science Foundation of China(No.52075218,51775232).
文摘Here,we demonstrate the assembly of a new stable lanthanide-based metal-organic framework(MOF),Eu(HDPB)(phen)(1)(HDPB=(1,1’:3’,1’’-terphenyl)-3,3’’,5,5’’-tetracarboxylic acid,phen=1,10-phenanthroline),with a three-dimensional framework under solvothermal conditions.1 showed strong red fluorescence emission at room temperature and could be used as a selective and sensitive chemical sensor for pH and folic acid(FA)detection.Moreover,1 could also be applied as a fluorescent material for the visible identification of fingerprints.Then,using 1 as a filler,two mixed-matrix membranes(MMMs),1@poly(ε-caprolactone)(PCL)and 1@poly(vinylidene difluoride)(PVDF),have been fabricated.Notably,owing to the hydrophobic protection provided by the polymer matrix of the MOF particles,these two MMMs also exhibited fluorescence emission comparable to that of 1 and could be used for FA sensing with good selectivity and remarkable recyclability.More importantly,this is the first time that Eu-MOF-based MMMs have been employed in FA detection.The fabrication of MOF-based MMMs not only provides a facile method for sensing biomarkers,but it also enhances the recyclability of sensors.
