30results about How to "Short response/recovery times" patented technology

The invention discloses a H2S gas sensitive sensor and a preparation method of Co-doped TiO2 nano-tube array films, and belongs to the technical field of electronic gas sensitive devices. According to the preparation method, TiO2 nano-tube arrays are prepared by the aid of an anodic oxidation method, transition metal is doped into the TiO2 nano-tube arrays, secondary treating of the TiO2 nano-tube arrays is omitted, complete transparent TiO2 nano-tube array films can be obtained, and the nano gas sensitive sensor is prepared by the aid of the array films and has good sensitivity and selectivity for hydrogen sulfide gas. The method is simple in preparation process, the prepared sensor has high selectivity and short response / recovery time for the hydrogen sulfide gas, and device of the gas sensitive sensor is achieved and has market development prospect.

The invention discloses a composite nano-film material based on the functionalization of graphene quantum dots. The composite nano-film material is in the shape of a film, the main body is ZnO nanosheets, and the surface is covered with graphene quantum dots and tin dioxide quantum grains; as The main ZnO nanosheets are hexagonal, with an average side length of 1.5-2.4 μm and an average thickness of 50-100 nm; the average size of graphene quantum dots is 3.2-4.3 nm, and the average size of tin dioxide quantum grains is 3.5- 5.2nm. The invention comprehensively uses the hydrothermal method and the post-heat steaming method to prepare the multi-level structure sensing material, and the synthesis method is simple and the cost is low.

The polyaniline / graphene capsule three-dimensional hollow hybrid structure, preparation method and application belong to the technical field of resistive gas sensor. In the polyaniline / graphene capsule three-dimensional hollow hybrid structure, the graphene capsule has a hollow opening structure, and the polyaniline nanoparticles are in-situ polymerized on the inner and outer surfaces of the graphene capsule, and form a π-π with the graphene capsule bond conjugation, wherein the polyaniline nanoparticles have a particle size of 18-40nm. The graphene capsule of the present invention is a hollow open capsule structure, and its curved part has more heterocyclic structures such as five-membered rings and seven-membered rings, which can form π-π bond conjugation with polyaniline, which makes polyaniline not a simple Attached to the inner and outer surfaces of graphene capsules, it forms a strong chemical bond and realizes the selective surface growth of polyaniline, so that the three-dimensional hollow hybrid structure is more stable and the carrier transport is more convenient, which is beneficial to the Fast response and increased sensitivity to gases.

A method for preparing a hydrogen-sensitive sensing material based on platinum nanoclusters / silicon carbide nanosheets, comprising the following steps: (1) surface treatment of silicon carbide nanosheets; (2) dripping an ethanol solution of chloroplatinic acid for infiltration; (3) High temperature reduction reaction. The surface of the platinum nanocluster / silicon carbide nanosheet hydrogen-sensitive sensing material prepared by the present invention is uniformly loaded with platinum nanoclusters, and has high selectivity and responsiveness to hydrogen, especially in a high temperature environment, which can detect hydrogen in the air. The in-situ detection is fast and highly sensitive, and has stable response value and short response / recovery time. The preparation method is simple and has wide application prospects.

The invention discloses an NH3 gas-sensitive element prepared from a WO3 micrometer spindle formed through self-assembly of nanometer rods and a preparing method of the gas-sensitive element, and belongs to the technical field of gas-sensitive elements of semiconductor oxide. The gas-sensitive element is mainly composed of an electrode element body and the WO3 micrometer spindle uniformly coatingthe electrode element body. The WO3 micrometer spindle is formed through self-assembly of the WO3 nanometer rods, the diameter of the WO3 micrometer spindle is 0.4-1.5 micrometers, the length of the WO3 micrometer spindle is 0.6-1.4 micrometers, the diameter of each WO3 nanometer rod is 15-33 nm, the length of each WO3 nanometer rod is 80-1,050 nm, and the WO3 micrometer spindle is of a hexagonal-phase crystal structure. The WO3 micrometer spindle formed through self-assembly of the nanometer rods has the advantages that the crystal phase is single, the crystallinity degree is high, the morphology is uniform and consistent, the porosity is high, and the specific surface area is large. The gas-sensitive element has the advantages of high selectivity on NH3 gas, quick responses to low working temperature and the like.

The invention provides a high-sensitivity surface acoustic wave nitrogen dioxide sensor, which sequentially includes a piezoelectric substrate, an electrode layer, and a NO sensor by ultraviolet light irradiation. 2 Sensing composite sensitive layer with three-dimensional porous structure of silver nanoparticles doped reduced graphene oxide-polypyrrole. This application uses the 3D porous sensitive material rGO‑PPy / Ag as the sensitive film, uses Ag nanoparticles doping to improve the repeatability of the sensor, and uses ultraviolet light to irradiate the sensitive film to assist NO 2 sensing. This rGO‑PPy / Ag surface acoustic wave NO2 sensor based on UV-assisted irradiation can realize NO at room temperature 2 Sensing with high sensitivity (127.68 Hz / ppm) and fast response / recovery speed (39.7 s / 58.5 s), exhibiting good repeatability and selectivity.

This application discloses a CdS / Co 3 o 4 Composite material and its preparation method and application, the CdS / Co 3 o 4 Composite materials include Co 3 o 4 Nanofibers are well attached to the Co 3 o 4 CdS nanoparticles between nanofibers, where the Co 3 o 4 The diameter of the nanofiber is 200-300nm, the diameter of the CdS nano-particle is 300-400nm, and the CdS / Co 3 o 4 The composite material can be made into a gas sensor, an acetone gas sensor, and a light-excited gas-sensing test platform. The CdS / Co 3 o 4 Composite materials and their products can detect acetone gas at room temperature (25°C), and have the advantages of high sensitivity, short response recovery time, good selectivity, etc., and a wide detection range, effectively solving the problem of traditional acetone gas sensors at low temperature and low temperature. The problem of poor gas sensitivity characteristics in the gas concentration area.