30results about How to "Improve gas sensing performance" patented technology

The invention discloses a SnO2 modified WO3 nanosheet composite gas-sensitive material as well as a preparation method and application thereof, and belongs to the technical field of inorganic composite materials. The preparation method comprises the following steps: dissolving WCl6 in ethanol, adding into a reaction kettle provided with a ceramic tube, carrying out hydrothermal reaction at 170-190 DEG C for 5-8 hours, taking out the ceramic tube, drying, and annealing to obtain a ceramic tube loaded with WO3 nanosheets; the preparation method comprises the following steps: dissolving SnO2, tin chloride and urea in water to obtain a mixed solution, adding the mixed solution into a reaction kettle filled with a ceramic tube loaded with a WO3 nanosheet, carrying out a hydrothermal reaction at 90-100 DEG C for 1-4 hours, taking out the ceramic tube after the reaction is finished, and drying to obtain the SnO2 modified WO3 nanosheet composite gas sensitive material, and enabling the SnO2 modified WO3 nanosheet to grow on the ceramic tube in situ. The preparation method is simple, the product is high in crystallinity and good in stability and is suitable for preparing a gas sensitive sensor material with high economical efficiency, and a sensor prepared from the SnO2 modified WO3 nanosheet composite gas sensitive material can effectively improve the gas sensitive performance of WO3 and shows an extremely high response value to nitrogen dioxide at a low temperature.

The invention relates to the technical field of gas sensing, and discloses a preparation method of nano tin oxide, nano tin oxide, tin oxide ink, a gas sensor and a preparation method of the gas sensor. The preparation method of the nano tin oxide comprises the following steps: mixing tin chloride dehydrate and ethanolamine to obtain a precursor mixed solution; treating the precursor mixed solution to obtain a complex solution; adding propionic acid into the complex solution to obtain tin oxide precipitate; and carrying out sintering treatment on the tin oxide precipitate to obtain the nano tin oxide. Ethanolamine and propionic acid are added in the process of preparing the nano tin oxide by using a sol-gel method, so that the health and safety risks are avoided, the pH value stability is favorably controlled, the uniformity and consistency of the nano tin oxide are ensured, and the gas sensing performance can be improved when the nano tin oxide is applied to a gas sensor. According to the invention, a sol-gel method and an ink-jet printing technology are combined, so that the preparation process of the gas sensor is simplified.

The invention discloses a method for in-situ construction of a Fe2O3 nanosheet array material on the surface of a ceramic tube, which comprises the following steps: by taking K3 [Fe (CN) 6] as a reaction raw material, 1-hexadecyl-3-methylimidazolium hexafluorophosphate as a surfactant and water as a reaction solvent, putting a mixed solution composed of the substances into a stainless steel reaction kettle, immersing the ceramic tube in the stainless steel reaction kettle, and carrying out in-situ construction of the Fe2O3 nanosheet array material on the surface of the ceramic tube; the preparation method comprises the following steps: putting a ceramic tube into a reaction kettle, reacting at 150-180 DEG C for 6-10 hours, after the reaction is finished, naturally cooling the ceramic tube to room temperature, respectively washing the ceramic tube with absolute ethyl alcohol and ultrapure water for multiple times, and then putting the ceramic tube into a vacuum drying oven for vacuum drying at 60-80 DEG C for 6-10 hours. The dried ceramic tube is subjected to roasting treatment in the air atmosphere at the temperature of 300-600 DEG C, the gas sensitive element covered with the Fe2O3 nanosheet array film sensitive layer is obtained, and the gas sensitive element has the good response characteristic to H2S gas at the operation temperature of 130 DEG C. The method has the effective benefit of solving the problem that almost all Fe2O3 materials constructed on the surface of a ceramic tube in situ by the existing method have one-dimensional nanorods and nanotube arrays, and the method is the first application of the Fe2O3 nanosheet array material in a gas sensor.

This invention discloses a chemiluminescence gas sensor based on polyoxometalates (POMs), and relates to its fabrication method and application. The sensor is suitable for detecting ammonia at room temperature. The gas sensor includes an adapter base and a sensing element, wherein the sensing element consists of interdigitated electrodes and a sensitive material loaded on the electrode surface. This sensitive material is a composite material of POMs and SnO2. POMs, as excellent electron acceptors, possess good redox properties, thermal stability, and photosensitivity. When combined with SnO2, they can effectively suppress electron-hole recombination, thereby significantly improving the gas-sensing performance of the semiconductor material. Compared with existing technologies, the sensor provided by this invention exhibits high response characteristics to ammonia at room temperature, while also demonstrating excellent selectivity and repeatability.

The invention relates to a laser modified ZnO-based gas sensor and a preparation method thereof. The ZnO-based gas sensor comprises an electrode substrate and a ZnO film arranged on the electrode substrate; the ZnO thin film is prepared through a magnetron sputtering method, annealing and laser etching treatment are sequentially carried out, and a regular net structure is formed on the surface of the ZnO thin film after laser etching. The preparation method comprises the following steps: preparing a ZnO film on the surface of an electrode substrate through magnetron sputtering; carrying out annealing treatment on the electrode substrate attached with the ZnO thin film; carrying out laser etching treatment on the surface of the annealed ZnO thin film to form a regular net-shaped structure; and assembling the electrode substrate attached with the laser modified ZnO film to finally obtain the ZnO-based gas sensor. Compared with the prior art, the surface of the ZnO film is modified through laser etching, and the assembled ZnO-based gas sensor has excellent sensitivity, selectivity, cycling stability and moisture resistance.

The invention provides a Sn-MOF (at) SnO2 / Fe2O3 multilevel structure nano composite material, a preparation method thereof and an n-butyl alcohol gas sensor, belongs to the technical field of material synthesis, and aims to solve the technical problem of poor gas sensitivity of a Sn-MOF induced metal oxide nano composite material. The preparation method of the Sn-MOF (at) SnO2 / Fe2O3 multilevel structure nano composite material comprises the following steps: adding a tin source, a ligand and alkali into a solvent I to prepare a mixed solution I, and then reacting to prepare Sn-MOF; adding the Sn-MOF, an iron source and an alkali precipitator into a solvent II to prepare a mixed solution II, and reacting under the microwave-assisted condition to prepare an Sn-MOF (at) SnO2 / Fe2O3 precursor; and calcining the Sn-MOF (at) SnO2 / Fe2O3 precursor to prepare the Sn-MOF (at) SnO2 / Fe2O3 nano composite material with the multilevel structure. According to the invention, the n-butanol gas sensor prepared by using the Sn-MOF-coated SnO2 / Fe2O3 multilevel structure composite material as the sensitive layer has good gas sensing performance. The optimal detection working temperature of the sensor on n-butyl alcohol gas is 200 DEG C, and meanwhile, the sensor has the advantages of high response speed, large response value, good long-term stability and the like.

The invention discloses an Ag monatomic modified In2O3 single crystal film prepared based on pulse voltage discharge, a method thereof and a gas sensitive sensor, and the method comprises the following steps: 1) placing a substrate in a vacuum cavity of magnetron sputtering equipment, taking an indium oxide target as an In source, and growing on the substrate through a magnetron sputtering technology to obtain an indium oxide single crystal film; the substrate is yttrium oxide stabilized zirconia (YSZ); (2) placing the indium oxide single crystal thin film obtained in the step (1) on a vacuum chamber sample table which is internally provided with a pulse voltage discharge electrode and an Ag target material, evaporating Ag particles based on a pulse voltage discharge process, and depositing the Ag particles on the surface of the indium oxide single crystal thin film material to form dispersed clusters; and annealing to obtain the Ag single atom modified In2O3 single crystal thin film. The synthesis of a sensitive material with a high atom utilization rate and a stable structure is realized, and an advanced NO2 gas sensing device with high sensitivity and high selectivity is obtained.

The invention discloses an NO2 gas sensing material, an NO2 gas sensor and a preparation method and application of the NO2 gas sensing material and the NO2 gas sensor. The NO2 gas sensing material is a semiconductor substrate material doped with variable-valence metal elements; the material of the semiconductor substrate is BiOX, and the element X is at least one of Cl, Br and I; the variable-valence metal element is a variable-valence transition metal element. The invention provides a design and preparation method of a gas sensor capable of rapidly detecting NO2 at room temperature. The method can realize reversible detection of NO2 at room temperature.

The invention relates to the technical field of gas sensors, and discloses a gas sensitive material, a preparation method thereof, a gas sensor and application, the preparation method of the gas sensitive material comprises the following steps: (1) mixing polyvinylpyrrolidone, polyacrylonitrile, MoS2 and N, N-dimethylformamide to obtain a spinning solution; (2) performing electrostatic spinning on the spinning solution to obtain a nanofiber membrane; (3) carrying out in-situ synthesis on SnO2 nanoparticles on the nanofiber membrane by adopting a solvothermal method; and (4) carrying out pre-oxidation treatment on the SnO2-loaded nanofiber membrane, and then calcining. The gas-sensitive material prepared by the method not only combines SnO2 and MoS2 which have high recognition ability to gas, but also combines CNFs (carbon nanofibers) which have high conductivity, high aspect ratio, large specific surface area and high stability, and the gas-sensitive material well maintains the structure of the carbon nanofibers, so that the gas-sensitive material has good application prospects. The gas-sensitive material has relatively high gas-sensitive performance and good selectivity and repeatability stability on hydrogen.

The application discloses a nano-needle self-assembled flower-shaped microsphere metastable indium oxide gas-sensitive material, a gas-sensitive element and a preparation method and application. The nano-needle self-assembled flower-shaped microsphere metastable indium oxide gas-sensitive material has a three-dimensional flower-shaped microsphere formed by nano-needle self-assembly, the diameter of the nano-needle is about 8 nm, the diameter of the flower-shaped microsphere is about 2-3 microns, the main exposed crystal face of the material is (104), and the crystal structure is a metastable rhombohedral corundum phase. The prepared nano-needle self-assembled flower-shaped microsphere metastable indium oxide successfully realizes preparation of pure metastable indium oxide material under mild conditions and realizes application in the field of gas-sensitive detection, especially in the detection of H2S, and has the advantages of low working temperature, high sensitivity, high selectivity and low detection limit. Meanwhile, the synthesis preparation method is simple in synthesis, low in cost and has good industrial production prospects.

The invention provides a palladium sulfide composite molybdenum disulfide hierarchical nanostructure based nitrogen dioxide sensor and a preparation method thereof, and belongs to the technical field of sensors and composite nanomaterials. The sensor comprises a substrate and a gas sensitive layer loaded on the substrate, the gas sensitive layer is a palladium sulfide-molybdenum disulfide composite nanomaterial, PdS nanoparticle clusters in the palladium sulfide-molybdenum disulfide composite nanomaterial are embedded in the surface of MoS2 nanoflowers, and PdS and MoS2 form a heterojunction, so that the separation and transmission rate of current carriers is increased, and the performance of the gas sensor is improved. Therefore, the gas-sensitive performance of the nitrogen dioxide sensor is improved, and the nitrogen dioxide sensor has a high response value and fast response recovery time for NO2 with ppm-level concentration.

The invention discloses a CuBTC / PAN composite nanofiber adsorption film and a preparation method and application thereof. The preparation method comprises the steps that copper salt and dimethyl sulfoxide are mixed, heated and stirred to obtain a metal salt solution; heating, stirring, separating, washing, heating and drying the organic ligand and a metal salt solution to obtain CuBTC precipitate; mixing polyacrylonitrile with dimethylformamide to obtain a faint yellow transparent viscous liquid, and carrying out electrostatic spinning to obtain a polyacrylonitrile nanofiber membrane; mixing the CuBTC precipitate with isopropanol, and performing ice-bath ultrasonic dispersion to obtain dark blue dispersion liquid; and spraying the dark blue dispersion liquid on the surface of the polyacrylonitrile nanofiber membrane, and drying to obtain the CuBTC / PAN composite nanofiber adsorption membrane. According to the present invention, the requirement of the good adsorption effect on the SF6 / N2 mixed gas decomposition components SO2F2 and NF3 is met.

The invention discloses an In 2 O 3 / 2D‑MoS 2 Heterojunction thin film material and preparation method and application thereof, the preparation method comprising the following steps: using magnetron sputtering method to deposit 2D-MoS 2 Surface preparation 2 O 3 The film forms a heterojunction thin film material; wherein, during magnetron sputtering, the gas flow is 15-25sccm, the gas pressure is 1-2Pa, the power is 10-20W, and the sputtering time is 25-35s. The present invention uses a method combining physical vapor deposition and chemical vapor deposition to design and construct In 2 O 3 / 2D‑MoS 2 Heterojunction. By optimizing the thickness, interface structure, interface quality, surface morphology, uniformity and crystallinity of heterojunction films, a new method was obtained that can significantly improve the gas (NO x ) Sensitivity of heterostructures In 2 O 3 / 2D‑MoS 2 Gas sensing materials.

The application discloses alkali metal doped MOF-74, a gas sensitive material, a gas sensitive sensor and a preparation method and application thereof, and belongs to the technical field of gas sensitive sensors. The application takes magnesium nitrate hexahydrate and 2,5-dihydroxyterephthalic acid as raw materials, in-situ adds alkali metal salt doping, takes triethylamine (TEA) as a deprotonating agent, optimizes a reaction process, rapidly performs synthesis of the alkali metal doped MOF-74 at room temperature, realizes miniaturization of the MOF-74 without losing crystallinity and high porosity, and is favorable for improving the gas sensitive performance of the material. The alkali metal doped MOF-74 is used for the gas sensitive sensor, has excellent selectivity and high sensing response to CO2 gas, and can meet the demand of CO2 gas detection. Moreover, the preparation period is short, heating is not needed, and the method is favorable for large-scale production.

The invention discloses SnS2 / ZnO nanoflowers as well as a preparation method and application thereof, and belongs to the technical field of gas sensing materials. According to the technical scheme, the preparation method comprises the following steps: 1) respectively dissolving tin chloride and thiourea into polyethylene glycol and deionized water, stirring, transferring the solution into a reaction kettle, carrying out hydrothermal reaction, cooling, washing and drying to obtain SnS2 nanoflowers; and 2) placing the SnS2 nanoflower in an ALD reaction chamber, and depositing ZnO on the SnS2 nanoflower by multiple ALD cycles to obtain the ZnO-loaded SnS2 nanoflower. According to the preparation method, the SnS2 / ZnO nanoflower is prepared by using an atomic layer deposition (ALD) technology, and the SnS2 / ZnO heterojunction is constructed, the method is based on an ALD surface self-limiting reaction, uniform nano materials are allowed to be deposited on a large area, and high-response sensors are allowed to be produced on a large scale.

The invention provides a Pd-WO3 gas-sensitive sensing material as well as a preparation method and application thereof, WO3 in the gas-sensitive sensing material is a two-dimensional ultrathin nanosheet, the crystal structure is a monoclinic phase crystal structure, and Pd nanoparticles are uniformly dispersed on the surface of the WO3 material. The Pd-WO3 gas-sensitive sensing material prepared by the method can be used for preparing a gas sensor of mustard gas and a simulating agent thereof, and can realize rapid and high-performance detection of the mustard gas and the simulating agent gas thereof; the gas sensor has good response / recovery, stability, high response, selectivity and the like to mustard gas and simulation agent gas thereof under the condition of lower than 300 DEG C.

The invention discloses a preparation method of a phosphorane room-temperature gas-sensitive material, which comprises the following steps: respectively adding Bi (NO3) 3.5 H2O and Na2MoO4. 2H2O into ethylene glycol, stirring until the Bi (NO3) 3.5 H2O and the Na2MoO4. 2H2O are completely dissolved, mixing the two solutions, and adding isopropanol to prepare a mixed solution; and transferring the obtained mixed solution into a high-pressure reaction kettle, carrying out solvothermal reaction at 160 DEG C for 15 hours, naturally cooling to room temperature after the reaction is finished, centrifuging, washing and freeze-drying to obtain the gas-sensitive material. The gas-sensitive material prepared by the method has good morphology and structure, and the successful preparation of the special litchi-shaped structure improves the electronic characteristics of the material and effectively enhances the gas-sensitive performance of the material.

The application discloses a kind of PdO-SnO2-SiO2 / SiO2 Self-supporting flexible gas-permeable nanofiber membrane gas sensor and preparation method thereof.Si electrospinning fiber is prepared by single needle head electrospinning method first, then Si electrospinning fiber and Pd-Sn electrospinning fiber interwoven fiber membrane is prepared on it by double needle head electrospinning method, then PdO-SnO2-SiO2 / SiO2 Flexible gas-permeable nanofiber membrane is obtained by heat treatment, finally electrode is prepared on its surface to obtain gas sensor.SiO2 Nanofiber in the sensor of the application has good flexibility, as a framework material to ensure the flexibility of the fiber membrane;Interwoven fiber membrane can effectively prevent SiO2 Nanofiber and PdO-SnO2 Nanofiber from separating, and has good gas permeability;At the same time, the fiber membrane is all inorganic material, which can maintain the original shape at high temperature, has good high temperature resistance and gas sensitivity.The sensor of the application has simple preparation process, stable performance, wide range of use, low cost, and has broad application prospect.

The present application relates to the field of gas measurement technology, and specifically to a MEMS gas sensor, a gas sensitivity testing method, device and system, the method comprising: determining the first influencing factor of the humidity response signal according to the discrete degree, change trend and average distribution of all humidity data in the humidity response signal; determining the second influencing factor of each IMF according to the difference between the energies of all adjacent sub-IMFs in each IMF, and the correlation between each IMF and the humidity response signal, and determining the correction factor of each IMF in combination with the first influencing factor to improve the gas-sensitive characteristics of the gas sensor. The present application compensates for the error caused by humidity by analyzing the differences within different components and the correlation between different components and ambient humidity, thereby improving the accuracy of the target gas concentration measurement.

This invention discloses a method and application for in-situ growth of Ti3C2Tx-titanium dioxide heterostructure material, belonging to the field of two-dimensional composite materials and gas sensor technology. The invention uses a hydrochloric acid solution containing fluorine compounds as the etching solvent and employs a hydrothermal method to etch Ti3AlC2 to prepare Ti3C2Tx material (Tx = -F, -OH, and -O). The Ti3C2Tx material is then subjected to oxygen microwave plasma treatment at low power, while controlling the oxygen volume fraction to 10-30%. This partially oxidizes the Ti3C2Tx material into two-dimensional sheet-like TiO2 oxides. These two-dimensional sheet-like TiO2 oxides tightly coat the surface of Ti3C2Tx, forming a Ti3C2Tx-TiO2 heterostructure material. Gas sensors prepared using this Ti3C2Tx-TiO2 heterostructure material exhibit excellent responsiveness and selectivity to hydrogen.

The invention discloses a gas sensor based on a zinc vanadate nano material, and relates to the technical field of preparation of gas sensors. The gas sensor comprises a substrate, an interdigital electrode and a sensitive layer material coated on the interdigital electrode, and the sensitive layer material is a ZnVO4 nano material. The zinc vanadate nano material is used as a sensitive layer material of the gas sensitive sensor, so that the gas sensitive sensor shows good gas sensing performance on a decomposition product SOF2 gas of SF6, and has the advantages of high sensitivity, high response and recovery speed and high environmental adaptability. In practical application, the gas-sensitive sensor can realize sensitive detection at a low SOF2 concentration, the response time is shortened to 5 min, the gas-sensitive sensor has good linear response characteristics, the sensor shows stable gas-sensitive performance after multiple cycle tests, and meanwhile, the sensor is made of a high-temperature-resistant and moisture-resistant material, can adapt to a high-temperature and high-humidity environment, and has wide application prospects. Good application prospects are realized.

The invention discloses a preparation method and application of an ultrathin two-dimensional In2O3-In2S3 heterojunction. The preparation method comprises the following steps: S1, preparing flower-shaped In2S3 by adopting a hydrothermal method; s2, dispersing the flower-shaped In2S3 by using water as a solvent, and preparing an In2S3 nanosheet by using an ultrasonic stripping method; s3, taking the flower-shaped In2S3 prepared in the step S1, and carrying out annealing treatment at the temperature of 450-550 DEG C to obtain In2O3; the preparation method comprises the following steps: dispersing In2O3 by using water as a solvent, and preparing In2O3 nanosheets by using an ultrasonic stripping method; s4, ethylene glycol and ethyl alcohol are added into the In2S3 nanosheet solution, and an In2S3 solution is obtained; formamide and ethyl alcohol are added into the In2O3 nanosheet solution, and an In2O3 solution is obtained; the In2S3 solution is dropwise added to a silicon wafer preheated to 45 DEG C, after the solution is volatilized, the temperature of the silicon wafer is increased to 200 DEG C, the temperature is kept constant for 1 h, then the temperature is decreased to 45 DEG C, the In2O3 solution is dropwise added, and after the solution is volatilized, the two-dimensional In2O3-In2S3 heterojunction is formed on the silicon wafer. According to the invention, the problem that the two-dimensional ultrathin In2O3-In2S3 heterojunction material is difficult to prepare is solved, and a novel heterojunction preparation method is created.

The present invention proposes a CuO / MoS2 / CuMoO4 multi-level structure nanocomposite material and its preparation method and application, which belongs to the technical field of material synthesis and is used to solve the technical problem of poor gas sensing performance of MoS2-based composite materials. The preparation method of the CuO / MoS2 / CuMoO4 multi-level structure nanocomposite material in the present invention comprises the following steps: dissolving and mixing a molybdenum source and a sulfur source in a solvent I, adjusting the pH, and obtaining a flower-shaped molybdenum disulfide composed of two-dimensional sheets through a hydrothermal reaction; dispersing and dissolving molybdenum disulfide and a copper source in a solvent II, reacting under microwave-assisted conditions, washing and drying the product; calcining the dried product in air to obtain a CuO / MoS2 / CuMoO4 multi-level structure nanocomposite material. The H2S gas sensor made of the CuO / MoS2 / CuMoO4 multi-level structure composite material of the present invention has good gas sensing performance. The optimal operating temperature of the sensor for H2S gas is 240°C, and the sensor also has the advantages of fast reaction and recovery speed, large response value, and good long-term stability.

The application relates to a ZnO / Bi2S3 photosensitization synergistic photothermal sensitization NO2 gas sensing material and a preparation method thereof, and belongs to the technical fields of nanomaterial preparation, atmospheric environment detection and gas sensors, and has a good application prospect. The characteristic is that porous ZnO precursors are prepared first, and then are combined with Bi2S3 to prepare ZnO / Bi2S3, porous ZnO particles are distributed on the outer wall of the flower-like Bi2S3, the recombination rate of electrons and holes is reduced by means of a type II heterojunction, and the gas sensing performance is improved. Under 365 nm light activation, the response value of the ZnO / Bi2S3 sensor to 100 ppm NO2 at room temperature is 1.73 times that under thermal activation (dark, 60 DEG C); 810 nm near-infrared light provides light activation and photothermal synergistic effect, the surface temperature of the gas sensor is increased to 47 DEG C, and the response value to 100 ppm NO2 is increased to 21.77.

The present invention provides a gas-sensitive material, a gas-sensitive sensor, and a preparation method and application thereof, which relate to the field of gas sensors. The preparation method of the gas-sensitive material comprises: soaking orange peel in a nickel nitrate solution to obtain a composite material having a metal nickel complex nanoarray on the surface; heat-treating the composite material to oxidize it to obtain a gas-sensitive material having a nickel oxide nanoarray on the surface. The present invention uses orange peel as a raw material, and the grown nickel oxide nanowires have a smaller size than the microspheres formed by agglomeration after general calcination, realizes the combination of nanomaterials and micron materials, has rich micro-nano structures and reactive sites, and is conducive to improving the gas-sensitive performance of the material; the raw materials for preparation have the advantages of being non-toxic and green, abundant and easy to obtain, and low in cost; the preparation process is simple and easy to operate; the gas-sensitive sensor prepared using the gas-sensitive material has excellent selectivity and high sensing response to ethylene glycol gas, which can meet the needs of ethylene glycol gas detection.

The invention relates to the field of sensor materials, and discloses a cobalt-nickel oxide doped graphene aerogel composite material as well as a preparation method and application thereof. The cobalt-nickel oxide doped graphene aerogel composite material is in a porous nanoflower shape, has a large specific surface area and more surface active sites, combines the advantages of a metal oxide semiconductor and graphene, and is beneficial to improving the gas-sensitive property. The preparation method of the cobalt-nickel oxide doped graphene aerogel composite material comprises the following steps: mixing cobalt salt, nickel salt, graphene and other raw materials, and then sequentially carrying out solvent heat treatment, freeze drying and calcination, so that a nano flower-shaped structure can be well maintained, and a large specific surface area can be maintained. When the aerogel composite material is used as a gas-sensitive material, the aerogel composite material shows high sensitivity and high selectivity to H2, and is beneficial to early warning of thermal runaway of the lithium battery.

The invention belongs to the technical field of gas sensors, and specifically relates to a high-performance hydrogen sensor for early detection of thermal runaway of lithium-ion batteries, a preparation method and a state monitoring system. The sensor comprises a sensing layer and a substrate, and the sensing layer is a sandwich structure consisting of a catalytic sensitization layer, a gas sensitive layer and an electron supply layer, which are Ag@SnO2 catalytic sensitization layer, SnO2 gas sensitive layer and g-C3N4 electron supply layer from top to bottom. The catalytic effect and overflow effect of Ag nanoparticles enable the sensor to have a shorter response / recovery time, a low detection limit, good stability and repeatability. At the same time, since the electron supply layer transports a large number of active electrons to the gas sensitive layer, coupled with the electron sensitization effect of the catalytic sensitization layer, the reaction activity of the gas sensitive layer is greatly improved, and the gas-sensitive performance of the sensor is further improved. The sensor has a high response value and good selectivity, and can well warn the occurrence of thermal runaway of the battery.

The application discloses an indium trioxide nanotube loaded cobalt oxyhydroxide composite material and application of the composite material in detection of nitrogen oxide, and the composite material is obtained by uniformly mixing indium trioxide nanotubes and Co / MOF in an aqueous solution, adding an etchant to fully react, washing the reaction product to neutral, and then drying to obtain the composite material; the organic skeleton raw material in the Co / MOF is dimethyl imidazole; and the etchant is sodium hydroxide or potassium hydroxide. The method has the advantages of simple process, low cost and no pollution to the environment; the indium trioxide nanotube has the advantages of excellent conductivity, large surface area and chemical stability, and the synthesized low-cost sensing material has high response value at room temperature, rapid detection and good stability, and has excellent selectivity to nitrogen oxide; the composite material has excellent gas sensing performance, and has excellent long-term stability and cycle stability, and has wide application prospect in the field of detection of nitrogen oxide.

This invention belongs to the field of gas sensor technology, specifically relating to an antimonate composite material based on heterogeneous isomorphism, its preparation, and its application. It utilizes bimetallic antimonate Ni... x Mg 1‑x Sb₂O₆ or antimonate / titanium dioxide composite Ni x Mg 1‑x A n-propanol gas sensor was fabricated using Sb₂O₆ / TiO₂ as the sensitive material. At the optimal operating temperature, it achieved a response value of over 35 for 20 ppm n-propanol, with a detection limit as low as 20 ppb and excellent selectivity. It shows great potential in environmental monitoring, industrial production, and early disease screening through breath analysis.

The present invention relates to a nanofiber cluster-shaped bismuth vanadate gas-sensitive material and a preparation method thereof, which is composed of a nanofiber stacked fiber cluster and independently dispersed nanofibers, wherein the diameter of the independently dispersed nanofibers is 5 to 50 nm, the diameter of the nanofiber stacked fiber cluster is 10 to 500 nm, and the nanofibers contain fiber gap micropores less than 2 nm, and the nanofiber stacked fiber clusters and the independently dispersed nanofibers overlap each other to form macropores of 50 to 150 nm. Preparation method: prepare a dilute nitric acid solution; dissolve bismuth nitrate pentahydrate and ammonium metavanadate in the dilute nitric acid solution respectively; add the ammonium metavanadate mixed solution dropwise to the bismuth nitrate mixed solution; add ammonia water; solvent thermal reaction; centrifuge; pour in anhydrous ethanol and rotate and shake; centrifuge and wash. This patented method does not require roasting, has low energy consumption, and is simple in process. The material of the present invention has high sensitivity to ethylene glycol gas, short response recovery time, and low operating temperature.