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Investigations on the sensing mechanism of Humidity Sensors Based on Poly(4-vinylpyridine)/carbon Black Composite by AC Impedance Spectra

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复旦学报（自然科学版） 2007年第5期46卷 796-页

作者： Hong Li-jie, Li Yang, Yang Mu-jie(Department of Polymer Science and Engineering, Zhejiang University,Hangzhou 310027, China) Department of Polymer Science and Engineering Zhejiang University Hangzhou 310027

1 Results Investigations on the sensing mechanism is important for understanding the electrical responses of humidity sensors to humidity change,and could provide guidelines for the design and synthesis of humidity sensitive materials with desirable *** this work,the sensing mechanism of humidity sensors based on quaternized poly(4-vinylpyridine) (PVP)/carbon black (CB) composite[1] was studied by measuring their AC impedance spectra at various humidities at room *** low humidity...

关键词： sensing mechanism poly(4-vinylpyridine) carbon black AC impedance spectra

TDDFT Study on Different sensing mechanisms of Similar Cyanide Sensors Based on Michael Addition Reaction

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Chinese Journal of Chemical Physics 2011年第3期24卷 305-310,I0003页

作者：李光跃宋平何国钟中国科学院大连化学物理研究所大连116023 中国科学院研究生院北京100041

The solvents and substituents of two similar fluorescent sensors for cyanide, 7-diethylamino- 3-formylcoumarin （sensor a） and 7-diethylamino-3-（2-nitrovinyl）coumarin （sensor b）, are proposed to account for their distinct sensing mechanisms and experimental phenomena. The time-dependent density functional theory has been applied to investigate the ground states and the first singlet excited electronic states of the sensor as well as their possible Michael reaction products with cyanide, with a view to monitoring their geometries and photophysieal properties. The theoretical study indicates that the protic water solvent could lead to final Michael addition product of sensor a in the ground state, while the aprotic acetonitrile solvent could lead to carbanion as the final product of sensor b. Furthermore, the Michael reaction product of sensor a has been proved to have a torsion structure in its first singlet excited state. Correspondingly, sensor b also has a torsion structure around the nitrovinyl moiety in its first singlet excited state, while not in its carbanion structure. This could explain the observed strong fluorescence for sensor a and the quenching fluorescence for the sensor b upon the addition of the cyanide anions in the relevant sensing mechanisms.

关键词： Sensor Fluorescence Cyanide sensing mechanism Time-dependent density functional theory Michael addition reaction

Fabrication Techniques and sensing mechanisms of Textile‑Based Strain Sensors:From Spatial 1D and 2D Perspectives

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Advanced Fiber Materials 2024年第1期6卷 36-67页

作者： Shilin Liu Wenting Zhang Jingzong He Yonggen Lu Qilin Wu Malcolm Xing State Key Laboratory for Modification of Chemical Fibers and Polymer Materials College of Materials Science and EngineeringDonghua UniversityShanghai 201620China Department of Mechanical Engineering University of ManitobaWinnipegMB R3T 2N2Canada

The intelligent textile sensors based on fiber(1D)and fabric(2D)are the ideal candidates for wearable *** flexible weaving and unique structure endow them with flexibility,lightweight,good air permeability,and feasible integration with *** view of the spring-up of novel textile-based strain sensors,the novel materials and fabrication approaches were elaborated from spatial perspectives,i.e.,1D fibers/yarn and 2D *** intrinsic sensing mechanism is the primary fac-tor affecting sensor sensitivity,and the variation trend of the sensing signal is closely related to *** existing studies have involved various sensing mechanisms,there is still lacking systematic classification and ***,the sensing mechanisms of textile-based sensors were elaborated from spatial *** that strain sensors were mostly based on resistance variation,the sensing mechanisms of resistive textile-based strain sensors were mainly focused,mainly including fiber deformation,tunneling effect,crack propagation,fabric deformation,electrical contact and bridge ***,the corresponding resistance prediction models,usually used as important data fitting methodology,were also comprehensively discussed,which can reproduce the resistance trend and provide guidance for the sensor ***,the multifunctionality of textile-based strain sensors was summarized,namely multi-mode signal detection,visual interaction,energy collection,thermal management and medical treatment were *** was expected to provide research insights into the multifunctional integration of textile sensors.

关键词： Textile sensors Fabrication approaches sensing mechanism Prediction model Multifunctionality

Preparation of single atom catalysts for high sensitive gas sensing

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International Journal of Extreme Manufacturing 2024年第3期6卷 216-248页

作者： Xinxin He Ping Guo Xuyang An Yuyang Li Jiatai Chen Xingyu Zhang Lifeng Wang Mingjin Dai Chaoliang Tan Jia Zhang Key Laboratory of Microsystems and Microstructure Manufacturing Ministry of EducationHarbin Institute of TechnologyHarbin 150080People’s Republic of China Institute for Frontier Materials Deakin UniversityWaurn Ponds CampusLocked Bag 20000Victoria 3220Australia School of Electrical and Electronic Engineering Nanyang Technological UniversitySingapore 639798Singapore Department of Electrical and Electronic Engineering The University of Hong KongPokfulam RoadHong Kong Special Administrative Region of China 999077People’s Republic of China Chongqing Research Institute Harbin Institute of TechnologyChongqing 401120People’s Republic of China

Single atom catalysts(SACs)have garnered significant attention in the field of catalysis over the past decade due to their exceptional atom utilization efficiency and distinct physical and chemical *** the semiconductor-based electrical gas sensor,the core is the catalysis process of target gas molecules on the sensitive *** this context,the SACs offer great potential for highly sensitive and selective gas sensing,however,only some of the bubbles come to the *** facilitate practical applications,we present a comprehensive review of the preparation strategies for SACs,with a focus on overcoming the challenges of aggregation and low *** research efforts have been devoted to investigating the gas sensing mechanism,exploring sensitive materials,optimizing device structures,and refining signal post-processing ***,the challenges and future perspectives on the SACs based gas sensing are presented.

关键词： single atom catalysts preparation sensing mechanism gas sensing

Synthesis and in-situ noble metal modification of WO3·0.33H2O nanorods from a tungsten-containing mineral for enhancing NH3 sensing performance

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Chinese Chemical Letters 2020年第8期31卷 2037-2040页

作者： Tingting Li Yanbai Shen Sikai Zhao Pengfei Zhou Xiangxi Zhong Shuling Gao Dezhou Wei Fanli Meng School of Resources and Civil Engineering Northeastern UniversityShenyang 110819China School of Information Science and Engineering Northeastern UniversityShenyang 110819China State Environmental Protection Key Laboratory of Mineral Metallurgical Resources Utilization and Pollution Control Wuhan University of Science and TechnologyWuhan 430081China

Ag-and Pt-doped WO3-0.33 H2O nanorods with high response and selectivity to NH3 were synthesized from a tungsten-containing mine ral of scheelite concentrate by a simple combined process,namely by a high pressure leaching method to obtain tungstate ions-containing leaching solution and followed by a hydrothermal method to prepare corresponding *** microstructure and NH3 sensing perfo rmance of the final products were investigated *** microstructure characte rization showed that the as-prepared WO3-0.33 H2 O nanorods had a hexagonal crystal structure,and Ag and Pt nanoparticles were uniformly distributed in the WO3-0.33 H2O nano *** sensing measurements indicated that Ag and Pt nanopa rticles not only could obviously enhance NH3 sensing properties in terms of response,selectivity as well as response/recovery time,but also could reduce the optimal operating temperature at which the highest response was *** highest responses of 22.4 and 47.6 for Agand Pt-doped WO3-0.33 H2O nanorods to 1000 ppm NH3 were obtained at 225 and 175℃,respectively,which were about four and eight folds higher than that of pure one at 250℃.The superior NH3 sensing properties are mainly ascribed to the catalytic activities of noble metals and the different work functions between noble metals and WO3-0.33 H2 O.

关键词： Scheelite concentrate Noble metal doping WO3·0.33H2O nanorods NH3 sensing mechanism

A novel fluorescent sensor for Al^(3+)and Zn^(2+)based on a new europium complex with a 1,10-phenanthroline ligand

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Journal of Rare Earths 2021年第4期39卷 460-468页

作者： Huimin Song Gang Liu Congbin Fan Shouzhi Pu Jiangxi Key Laboratory of Organic Chemistry.Jiangxi Science and Technology Normal University Nanchang 330013China

A new europium complex Eu(tta)_(3)Li(la)based on 1,10-phenanthroline derivative(Li=(2-(3,5-dimethoxyphenyl)-1 H-imidazo[4,5-f][1,10]phenanthroline),tta=2-thenoyItrifluoroacetone)was designed and *** structure was characterized by^(1)H and^(13)C NMR,elemental analysis,UV-vis,fluorescence spectra and single crystal X-ray *** crystal of the complex la belongs to monoclinic system with the space group P2_(1/n).The europium complex la in the solid and in the solution displays the typical emission of Eu(III)ion centered at 612 nm as a result of the electric dipole transition(^(5)D_(0)-►^(7)F_(2)).It exhibits high quantum yield(20.42%),long lifetime(0.29 ms)and good CIE color coordinate(0.67,0.33)in *** addition,the complex shows high sensitivity and selectivity towards Al^(3+)and Zn^(2+)in methanol solution which can be attributed to the Al^(3+)/Zn^(2+)cation instead of Eu^(3+)in the complex *** LODs for Al^(3+)and Zn^(2+)were calculated to be 5.880×10^(-7)and 7.678×10^(-8)mol/L,***,the additions of Al^(3+)and Zn^(2+)express remarkable color changes from red to bright blue and ivory that can be clearly observed by the naked eye respectively.

关键词： Europium complex Fluorescence Al^(3+),Zn^(2+)detection CIE chromaticity coordinates sensing mechanism Rare earths

Recent developments of nanomaterials-based conductive type methane sensors

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Rare Metals 2021年第6期40卷 1515-1527页

作者： Ming-Zhi Jiao Xiao-Yu Chen Ke-Xiang Hu De-Yu Qian Xiao-Hu Zhao En-Jie Ding Research Center for Internet of Things State and Local Joint Engineering Laboratory of Perception MineChina University of Mining and TechnologyXuzhou 221008China Jiangsu Key Laboratory of Fire Safety in Urban Underground Space China University of Mining and TechnologyXuzhou 221008China School of Mines China University of Mining and TechnologyXuzhou 221116China

Methane is an explosive gas in coalmines and needs to be monitored by methane *** methane sensors are small,simple and stable,and they are very promising for mining safety or home safety *** can even be employed in mining Internet of things if the power consumption can be lowered down to few *** researches of nanomaterialsbased conductive-type methane sensors have been reported *** review intends to present a comprehensive and critical summary on the recent progresses in the nanomaterials-based conductive-type methane sensors *** excellent methane-sensitive nanomaterials will be present,such as SnO2,ZnO,TiO2,WO3,carbon nanotubes,graphene,rare earth metal-based perovskite oxides and their *** attention is given to the synthetic methods of the nanomaterials,sensing mechanisms of the nanomaterials and the relationship between the sensing performance and the structures and components of the ***,the future trends and perspectives of nanomaterials-based conductive-type methane sensors are proposed.

关键词： Nanomaterials Methane sensors Conductive gas sensors sensing mechanism

Recent Progresses in Lanthanide Metal-Organic Frameworks(Ln-MOFs) as Chemical Sensors for Ions, Antibiotics and Amino Acids

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Chinese Journal of Structural Chemistry 2022年第11期41卷 45-70页

作者： Yan Yang Shuting Xu Yanli Gai Bo Zhang Lian Chen College of Chemistry and Chemical Engineering Liaocheng UniversityLiaocheng 252059China State Key Laboratory of Structure Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China School of Chemistry and Materials Science Jiangsu Normal UniversityXuzhouJiangsu 221116China

Various ions and antibiotics,widely used in industry and clinical medicine,respectively,are massively discharged to atmosphere and water,resulting in severe pollutions on environment and potential threats to human ***,amino acids,the primary substances for the establishment of proteins,cells and tissues,are crucial to human ***,seeking effective and practicable materials to detect aforesaid analytes is vitally ***-organic frameworks centered with lanthanide ions(Ln-MOFs),also known as lanthanide coordination polymers,are considered as a charming category of multi-functional hybrid crystalline materials with fascinating structures and incomparable luminescent *** from their unique merits,Ln-MOFs have been largely developed as excellent luminescent sensors for fast and efficient sensing various *** this review,we aim to introduce some of the recent researches between 2018 to 2022 on Ln-MOFs applied as chemical sensors for ions,antibiotics and amino acids based on luminescent quenching and enhancing effects,and provide an update and summary for the latest progresses in this field.

关键词： lanthanide metal-organic frameworks luminescence luminescent sensors sensing mechanism

Recent Progress on Smart Fiber and Textile Based Wearable Strain Sensors:Materials,Fabrications and Applications

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Advanced Fiber Materials 2022年第3期4卷 361-389页

作者： Xuhua Liu Jinlei Miao Qiang Fan Wenxiao Zhang Xingwei Zuo Mingwei Tian Shifeng Zhu Xueji Zhang Lijun Qu Research Center for Intelligent and Wearable Technology College of Textiles and ClothingState Key Laboratory of Bio-Fibers and Eco-TextilesCollaborative Innovation Center for Eco-Textiles of Shandong ProvinceQingdao UniversityQingdao 266071ShandongPeople’s Republic of China School of Biomedical Engineering Shenzhen University Health Science CenterShenzhen 518060GuangdongPeople’s Republic of China

With the rapid development of smart products,fexible and stretchable smart wearable electronic devices gradually play an important role,and they are considered as the pioneers of the new generation of fexible electronic *** these intelligent devices,fexible and stretchable strain sensors have been widely studied for their good fexibility,high sensitivity,high repeatability and huge potential for application in personal healthcare and motion ***,unlike traditional rigid bulky sensors,the high-performance fexible strain sensors are lightweight portable devices with excellent mechanical and electrical performance,which can meet personalized needs and become more ***,the research progress of fexible strain sensors in recent years are reviewed,which mainly introducing the sensing principles and key parameters of strain sensors,commonly used conductive materials and fexible substrates and common preparation methods,and fnally proposes the future application and prospects of strain sensors.

关键词： Flexible strain sensor sensing mechanism Wearable electronics Personal healthcare Motion detection