33results about How to "Good gas response" patented technology

The invention belongs to the technical field of gas sensors, and relates to a gas sensor based on a metal molybdate nanocomposite and a preparation method thereof. An annular gold electrode of the sensor is coated with a metal molybdate nanocomposite film; the specific preparation process of the metal molybdate nano composite material comprises the following steps: firstly, preparing MoS2 powder from ammonium molybdate, thiourea, ammonium fluoride and the like according to a hydrothermal synthesis method, and meanwhile, preparing a semiconductor metal oxide suspension from semiconductor metalsalt through the hydrothermal synthesis method; carrying out hydrothermal synthesis on the molybdenum sulfide powder and the semiconductor metal oxide suspension liquid to obtain a molybdenum sulfidenano composite material precursor, and calcining the prepared molybdenum sulfide nano composite material precursor in an atmosphere to obtain a metal molybdate nano composite material. The ethanol gassensor has the advantages of high selectivity, high sensitivity, good stability, long service life, short response time and recovery time to ethanol gas, excellent performance, and rapid and timely ethanol gas alarm.

The invention discloses an electrodeless semiconductor gas sensor and a preparation method thereof. By adopting the electrodeless-type design, a gas sensitive layer is produced from a colloidal-state nano crystal composite material which is high in sensitivity and good in conductivity, the gas sensitive layer is smeared on an insulation substrate to form a device, no additional signal electrode is needed, the device structure and the process procedure are simple, the cost is reduced, and the mass production can be realized; moreover, the method is suitable for producing a flexible gas sensor. The gas sensor has characteristics of light weight, thinness, shortness, small size and good portability; moreover, the working temperature is low, and the application prospect is good.

The invention provides a novel ammonia gas sensor based on a reduced graphene oxide-tungsten disulfide composite and a preparation technology thereof and belongs to the technical field of sensors. The novel ammonia gas sensor comprises a gas-sensitive composite and a sensor substrate, wherein the gas-sensitive composite is a nano material obtained through one-step hydrothermal synthesis, the gas-sensitive composite is uniformly coated on a gold interdigitated electrode on the sensor substrate, transient heating temperature of a heating plate on the back of the sensor substrate is 140 DEG C, and heating recovery time is linearly varied along with concentration of detected gas. The reduced graphene oxide-tungsten disulfide composite disclosed by the invention shows good response performance on ammonia gas in a room temperature environment and has good selectivity, stability and repeatability. In a recovery stage of the gas sensor provided by the invention, transient heating is used, time required for reduction is effectively shortened without influencing performance of a gas-sensitive material, and concrete transient heating time can be set according to the gas concentration obtained through detection.

The invention discloses a tungsten trioxide gas-sensitive film material, a tungsten trioxide-based composite gas-sensitive film material, and preparation methods and applications of the tungsten trioxide gas-sensitive film material and the tungsten trioxide-based composite gas-sensitive film material, wherein a tungsten trioxide thin gas-sensitive material with a nanometer structure is directly prepared on an electrode substrate through in-situ solution deposition, and second phase oxide compounding is performed at the prepared tungsten trioxide thin film through a sol-gel method to obtain a tungsten trioxide-based composite gas-sensitive film material. According to the present invention, the tungsten trioxide film with the nanometer structure can be subjected to direct deposition growth on the electrode substrate; the prepared nanometer structure tungsten trioxide thin film and the composite thin film based on the nanometer structure tungsten trioxide have the network-like structure formed by the nano-sheets growing perpendicular to the substrate; the method has advantages of high efficiency, low cost and simple process, and is suitable for industrial production; and the obtainednanometer structure tungsten trioxide film has a large specific surface area, can effectively overcome the agglomeration problem among nanoparticles, has good gas-sensitive response to gases such as NO2, H2S and the like, and has excellent gas-sensitive application prospect.

The invention belongs to the field of comprehensive recycling of industrial waste tin, environmental protection and semiconductor oxide formaldehyde gas sensors, and relates to a preparation method offormaldehyde gas sensitive materials based on tin mud modification in a tin plating process and an application. The formaldehyde gas-sensitive materials are prepared from waste tin mud existing at the bottom of a plating bath on a tin plating production line by acidification activation, washing, drying, noble metal doping and subsequent heat treatment. The prepared gas sensor has excellent gas-sensitive performance such as high sensitivity, fast response, high recovery speed and the like for formaldehyde. Effective and reasonable utilization of tin resources is realized, the economic cost isreduced, environmental pollution caused by waste is reduced, and the preparation method is environmentally friendly.

The invention discloses a wireless passive H2 gas sensor based on WO3 and a preparation method thereof. The gas sensor comprises a ceramic substrate, and an inductance coil and a composite gas sensitive resistor, which are printed on the ceramic substrate, wherein an outer end of the inductance coil is connected with one end of the composite gas sensitive resistor through silver paste filled in athrough hole in the ceramic substrate, and an inner end of the inductance coil is connected with the other end of the composite gas sensitive resistor to form an LR sensitive circuit; the ceramic substrate is made of an aluminium oxide raw ceramic tape and is prepared by an HTC process, the inductance coil is prepared by silk-screen printing process with Ag as paste, and the composite gas sensitive resistor is prepared from a Pt-WO3 composite material by a magnetron sputtering process. The gas sensor disclosed by the invention uses a wireless non-contact measurement method, can accurately realize the detection of a gas H2 to be measured under low temperature conditions by analyzing the threshold that changes with resistance, adopts the mature silk-screen printing process and the magnetronsputtering preparation process, and has the advantages of simple and convenient processing, low cost, etc.

The invention discloses a zinc oxide gas-sensitive film material, a preparation method therefor and an application of the zinc oxide gas-sensitive film material. A nanostructure zinc oxide film is directly prepared on an electrode substrate by using solution low-temperature in-situ deposition. The prepared nanostructure zinc oxide film has a network-shaped structure formed by nanosheets growing vertical to the substrate. The zinc oxide gas-sensitive film material has the advantages of high efficiency, low cost and simple process and is suitable for being industrially produced. The obtained nanostructure zinc oxide film has a relatively large specific surface area, the problem of agglomeration among nanoparticles can be effectively overcome, and the zinc oxide gas-sensitive film material has good gas-sensitive response to gases such as NO2 and H2S and has an excellent gas-sensitive application prospect.

The invention discloses a Ni-modified Nb2O5 gas sensitive element and a preparation method and application thereof. The preparation method includes the steps that after a washed FTO interdigital electrode slice is subjected to a hydrothermal reaction in a mixed solution containing Ni(NO3)2.6H2O and ammonium niobate oxalate hydrate, the FTO interdigital electrode slice with powdery NiO/Nb2O5 growing on the surface is taken out, washed with deionized water, dried, calcined at high temperature and reduced; and the NixO/Nb2O5 gas sensitive element generated by the in-situ hydrothermal method is prepared. The NixO/Nb2O5 gas sensitive element obtained by the invention shows better response performance to CO2 and H2 under the conditions of room temperature and ultraviolet light, and has good stability and repeatability, the preparation process of the gas sensitive element is simplified, and the NixO/Nb2O5 gas sensitive element has a better application prospect in the aspect of preparation of semiconductor photo-assisted gas sensitive sensors.

The invention provides a gas reaction continuous cavity and a gas reaction method using the gas reaction continuous cavity. The gas reaction continuous cavity comprises a preheating chamber, a reaction chamber and a cooling chamber which are sequentially arranged, each of the chambers is positioned between two isolating devices, the plurality of isolating devices can ensure that the plurality of chambers are in an air-tight state, a conveying device is positioned in the plurality of chambers and the isolating devices and used for driving a reacted object to move so as to pass through the plurality of chambers, each of the plurality of chambers is provided with an upper heater which acts towards the top surface of the reacted object to adjust the temperature of the reacted object, and each of the reaction chamber and the cooling chamber is provided with a reaction gas input opening. Therefore, the gas reaction method provided by the invention can ensure the gas reaction of the reacted object and has good efficiency.

The invention discloses a room-temperature NO2 sensor based on a ZnO microsphere and CsPbBr3 quantum dot heterostructure composite material and a preparation method thereof, and belongs to the technical field of semiconductor oxide gas sensors. The sensor is composed of a ceramic chip substrate with a metal interdigital electrode and a ZnO microsphere and CsPbBr3 quantum dot heterostructure composite material sensitive layer coating the metal interdigital electrode. The morphology of zinc oxide is of a sphere structure, has a large specific surface area, and can provide more attachment sites, so that zinc oxide is in full contact with perovskite CsPbBr3 quantum dots with small sizes, and a gas sensitive element with good gas sensitive response and high response recovery speed is obtained. In addition, the CsPbBr3 quantum dots are used as an excellent photoelectric material and can absorb visible light, so that more photon-generated carriers are provided. The sensor provided by the invention adopts a planar structure, and is simple in process, short in manufacturing period and suitable for mass production.