163 results about "Nanowire array" patented technology

The invention relates to an optical fiber hydrogen sensor based on a silver film-nanowire hole array structure and a preparation method thereof in the field of photochemical sensors. The optical fiber hydrogen sensor comprises a multimode optical fiber, and a sensing area is formed on the multimode optical fiber; the sensing area is formed by stripping a coating layer with a preset length from the multimode optical fiber, thinning the optical fiber in the area, plating a silver film on the surface of the thinned optical fiber, and adsorbing a nanowire hole array structure which is sequentially and vertically arranged on the surface of the silver film in a liquid level self-assembly manner; the nanowire hole array is of a metal-medium-metal (MIM) structure, a gold-palladium nanowire array is arranged at the bottom, an intermediate medium layer is made of aluminum oxide, and a silver film with a hole array in any shape is arranged at the top. When light is transmitted to a sensing area from a fiber core of the multimode optical fiber, the light and a metal silver film can excite a surface plasmon resonance (SPR) effect, meanwhile, an MIM structure formed by a gold-palladium nanowire, an aluminum oxide dielectric layer and a porous silver film serves as an optical coupling antenna through a local surface plasmon resonance (LSPR) effect at the edge of a top hole, and the optical coupling antenna is used for transmitting the light to the sensing area. Light energy is efficiently converged and excited in an extremely bound gap plasmon (Gap Plasmon) in an aluminum oxide dielectric layer, so that far-unconventional electromagnetic field enhancement is generated in a sensing core area, and the sensitivity of the sensor is greatly improved.

The invention discloses a deep ultraviolet LED epitaxial structure, a deep ultraviolet LED device comprising the same and a preparation method, and the epitaxial structure sequentially comprises a sapphire substrate, an AlN nanowire array layer, an AlN intrinsic layer and an AlGaN light-emitting structure layer from bottom to top. The AlGaN light-emitting structure layer further comprises an n-type AlGaN electron injection layer, a quantum well active layer, a p-type AlGaN electron blocking layer and other device structures. According to the invention, the vertically arranged AlN nanowire array is introduced to replace a traditional AlN buffer layer, so that lattice mismatching stress caused by a substrate is significantly released, and the dislocation density of an epitaxial layer is effectively reduced; meanwhile, the introduction of the AlN intrinsic layer further flattens the epitaxial interface and optimizes the lattice quality, thereby providing a high-quality template for the growth of a high-performance AlGaN material. The epitaxial structure is suitable for an LED device in a deep ultraviolet band, and the crystal quality, the electrical property and the luminous efficiency of the device can be improved.

The invention belongs to the technical field of photoelectric detection, and relates to a gallium oxide nanowire array type solar blind photoelectric detector and a preparation method thereof. Spreading liquid metal gallium on the surface of the substrate to form a liquid metal gallium layer on the surface of the substrate; performing vacuum evaporation on the surface of the liquid metal gallium layer to form a gold film layer to obtain a device precursor; and heating the device precursor to 400-1000 DEG C at a heating rate of 10-15 DEG C / min, and carrying out heat treatment for 1-2h to obtain the sandwich structure device. According to the method, the preparation mode of the array type gallium oxide nanowire is simplified, gallium metal left in the growth process is used as the electrode, the tedious and complex technological process needed in the previous device preparation process is improved, the ordered and regular gallium oxide nanowire array structure is prepared, and the photoelectric detection effect is improved.

The invention relates to an electrochemical induced metal oriented growth method based on a gallium-based liquid metal substrate, and belongs to the technical field of electrochemical materials. According to the present invention, the dynamic smooth interface and the low lattice mismatch characteristic of the liquid metal are utilized, the reduction kinetics of the metal ions is regulated and controlled through the constant current mode, the high orientation degree growth of the crystal along the specific crystal face (such as Zn (002) and In (111)) is achieved, and the prepared deposited metal dominant crystal face has the high orientation degree. The problems of stress accumulation and dendritic crystals of a traditional solid substrate can be solved, and the method is suitable for green preparation of nanowire arrays and functional coatings; and the process is simple and convenient to operate, easy in control of process parameters and suitable for batch production.

A MEMS gas sensor and a preparation method therefor, comprising an insulating substrate (1), a heating electrode (403), an insulating layer (105) and a testing unit, which are overlappingly disposed. The testing unit comprises a testing electrode, a sensing unit (2), and a selective separation membrane (3); the sensing unit (2) has a nanowire array structure formed by multiple nanowires disposed at intervals, and the selective separation membrane (3) covers the surface of the sensing unit and a recessed portion; the nanowires comprise a first metal and a second metal, the first metal being Pd, and the second metal being at least one selected from Ni, Cu, Ag, Au and Ir; the selective separation membrane (3) comprises an inner separation membrane (301) and an outer separation membrane (302) which are stacked in sequence; the inner separation membrane (301) comprises polytetrafluoroethylene, and the outer separation membrane (302) is a mixed matrix membrane having a covalent organic framework material as a filler and a polymer of intrinsic microporosity as a matrix. The MEMS gas sensor possesses excellent sensitivity for low-concentration gas monitoring, and tolerance stability for high-concentration gas, as well as excellent anti-interference performance and response speed.

This invention discloses an ocular implant and its delivery system, comprising: a flexible substrate; multiple nanowire arrays disposed on the flexible substrate; an elastic ring disposed along the circumferential edge of the flexible substrate, the elastic ring having elastic memory and capable of returning to its original shape before deformation after deformation; and two opposing openings disposed near the edge of the flexible substrate. The nanowire array of the ocular implant of this invention can be composed of multiple materials spliced ​​together, and materials with different efficacies and photosensitive wavelengths can be selected for splicing. Therefore, personalized ocular implants can be customized according to different patient conditions to achieve a better match with the patient's fundus condition. Furthermore, the folding and opening design of the ocular implant of this invention, as well as the self-expanding property of the elastic ring, enable it to be adapted to a delivery system for positioning and minimally invasive implantation.

This invention discloses a frustum-shaped flexible photoelectric energy conversion module, comprising an optical fiber connector, a housing, and a photovoltaic cell. The optical fiber connector is fixedly disposed on the top of the housing. A frustum-shaped cavity is formed within the housing, and the photovoltaic cell is fixed within the cavity. The photovoltaic cell is a three-dimensional flexible energy transfer chip comprising multiple sub-cells connected in series. Each sub-cell comprises multiple arrayed nanowires with a radial PIN structure. A wire interface is provided on the housing. The input end of the photovoltaic cell is connected to an external input device via the optical fiber connector, and the output end of the photovoltaic cell passes through the wire interface and is connected to a power-consuming device. In this invention, the use of a nanowire array structure for the sub-cells increases the specific surface area, expands the longitudinal absorption area, saves projected area, reduces volume, and improves heat dissipation. Simultaneously, the nanoarray structure can significantly improve the light-harvesting capability and charge separation efficiency of the cell.

The invention relates to a copper-cobalt bimetallic phosphide heterojunction and a preparation method and application thereof.The preparation method comprises the following steps that 1, pretreated foamy copper is soaked in an ammonium persulfate and sodium hydroxide solution, and the substance serves as a strong oxidant and is used for reacting to form copper hydroxide; (2) mixing cobalt nitrate hexahydrate with methanol, and putting copper hydroxide to react for two days; 3) adding dimethylimidazole for continuous reaction, and then washing, drying and phosphorizing at room temperature; compared with the prior art, the preparation method is simple in process and low in cost; the prepared catalyst has a heterojunction nanowire array structure, more active sites are provided, charge redistribution at a phosphide heterojunction interface is promoted by electron directional movement, the electron structure of the catalyst can be adjusted, and adsorption energy of reactants and intermediates on the active sites can be changed, so that reaction kinetics is promoted. The catalyst product is mainly ammonia gas, is good in stability and can be repeatedly used for multiple times.

The present invention relates to a method for preparing magnetic nickel tapered nanowires, comprising the following steps: (1) irradiating and sensitizing a polymer template with a latent track by a fast heavy ion beam; (2) sputtering a gold conductive layer on one side of the polymer template with the latent track, and then depositing a copper conductive layer on the surface of the gold conductive layer by electrochemical deposition; (3) etching the side of the polymer template with the latent track without the gold-copper conductive layer using an etching solution to obtain a polymer template with tapered linear channels; (4) electrochemically depositing magnetic nickel tapered nanowires on the side of the polymer template with the tapered linear channels without the gold-copper conductive layer; and (5) stripping the gold-copper conductive layer to obtain the magnetic nickel tapered nanowires. The present invention is simple and efficient, and for the first time achieves the controllable preparation of magnetic nickel tapered nanowire arrays, successfully preparing small-sized magnetic nickel tapered nanowire arrays with excellent microwave absorption performance.

The invention discloses a wafer room temperature bonding method and application thereof, and belongs to the technical field of semiconductor advanced packaging and three-dimensional integration. The method comprises the following steps: providing a first wafer, and sequentially preparing a metal plane layer and an oxide layer on the surface of one side of the first wafer to form a metal / oxide composite layer; selectively etching the metal / oxide composite layer to remove the oxide layer and form a metal nanowire array layer on the metal plane layer; providing a second wafer, and preparing a metal material layer on the surface of one side of the second wafer; and aligning the surface, with the metal nanowire array layer, of the first wafer with the surface, with the metal material layer, of the second wafer, and then bonding. According to the invention, the metal nanowire array is introduced into the bonding interface, so that the nanowires are subjected to plastic deformation and local surface diffusion under the action of external pressure, that is, compact and reliable metal-metal bonding can be realized in a room temperature environment, and the requirements of a low-temperature process window and high strength are both considered.

This invention discloses a method for preparing Co-P3 / S-TiO2 nanowire array materials, along with their products and applications. Through a hydrothermal-etching-phosphating method, Co single atoms coordinated with P were successfully anchored on the surface of a TiO2 nanowire array rich in step defects, resulting in the Co-P3 / S-TiO2 nanowire array material. Under the dual regulation of the special step structure and the suitable electronegativity of P, the Co metal atom becomes an electron-rich center, exhibiting superior adsorption capacity and a unique coordination environment, thus possessing excellent electrocatalytic hydrogen evolution performance. The preparation process is simple, and the raw materials are inexpensive. This invention provides inspiration for the design and synthesis of single-atom catalysts and their application in the field of electrocatalytic water electrolysis.

The invention provides a nano array for exposing a SnO2 high-activity crystal face, a preparation method of the nano array and application of the nano array in hydrogen sensing. The preparation method of the Pd-SnO2 nanowire array comprises the following steps: (1) synthesizing a SnO2 nano array on the surface of a substrate; and (2) loading the Pd nano particles on the SnO2 nano array, so as to obtain the Pd-SnO2 nanowire array. The palladium nanoparticle-loaded SnO2 nanowire array can rapidly and sensitively detect hydrogen under a low-temperature condition, has excellent sensitivity, shows excellent selectivity and reliable stability, has a detection lower limit reaching a ppm level, and is high in response speed and good in reproducibility. When the palladium nanoparticle loaded SnO2 nanowire array is used for preparing a hydrogen sensing device, the energy consumption is reduced, and the hydrogen sensing device is safer and more environment-friendly.

The invention relates to the technical field of detectors, in particular to a graded silicon nanowire metasurface, a manufacturing method thereof and a silicon-based photoelectric detector, and the silicon-based photoelectric detector comprises the graded silicon nanowire metasurface. The graded silicon nanowire metasurface comprises a silicon substrate, one side of the silicon substrate comprises a side top surface and at least one stage of groove surface generated by etching along the side top surface, and the etching depths of any stage of groove surface are different; and the graded silicon nanowire is integrally formed on one side of the silicon substrate and comprises a silicon nanowire array which is formed at least depending on the groove surface. The narrow-band selective absorption / emission device has the advantages of realizing narrow-band selective absorption / emission, keeping high hotspot density, low cost, easiness in batch processing and the like, and has the potential effect of realizing high-dimensional detection requirements.

The invention discloses a TiO2 composite photo-anode material based on ZIF-8 and MXene synergistic modification and a preparation method of the TiO2 composite photo-anode material. The material comprises an FTO conductive substrate, a vertically arranged TiO2 nanowire array, an in-situ grown ZIF-8 pore structure layer and an MXene two-dimensional conductive sheet layer spin-coated and loaded on the surface of the ZIF-8 pore structure layer, and a TiO2 / ZIF-8 / MXene multi-layer composite heterostructure is constructed and formed. The preparation method sequentially comprises the steps of FTO substrate cleaning, hydrothermal synthesis and annealing of the TiO2 nano array, in-situ growth of ZIF-8, spin-coating loading of MXene and annealing treatment. According to the material, space separation channel design of electrons and holes is achieved, the service life of photon-generated carriers is remarkably prolonged, the migration efficiency of the photon-generated carriers is remarkably improved, and compared with original TiO2, the light current density, the interface charge transfer impedance, the carrier concentration and the stability of the composite photo-anode material are remarkably improved.

This invention discloses a ligand-free electrodeposition method for growing platinum nanowire arrays on a substrate, with lengths reaching up to approximately 10 μm. The method exhibits a wide deposition potential range of -0.5 V to -7 V. By adjusting the deposition time, the length of the platinum nanowires can be controlled on the substrate without a template or small molecule ligands. Furthermore, the density of the platinum nanowires can be controlled by varying the concentration of the silane coupling agent. Moreover, this synthesis can be extended to conductive substrates, allowing the platinum nanowire arrays to be directly used as working electrodes, providing significant application potential in fields such as electrocatalysis. This invention offers advantages such as simple process, mild reaction conditions, low cost, and the precise controllability, ease of operation, and environmental friendliness of electrodeposition for synthesizing nanomaterials.

The application belongs to the field of electrochemical detection, and particularly relates to a water-vapor self-powered sensor for lincomycin detection and a preparation method thereof. A glass substrate is used as a substrate, a copper foil tape is used as a positive electrode and a negative electrode, a ZnO nanowire array and Ce-MOF are used as power generation materials to prepare a water-vapor generator, and a lincomycin aptamer is assembled to construct a light-assisted water-vapor self-powered sensor. The power generation material is a composite material of the ZnO nanowire array and the Ce-MOF. The light assistance is combined into the water-vapor self-powered sensor, and the water-vapor self-powered sensor significantly improves the generated electric output under the light assistance. The application widens the application of the ZnO nanowire array and the Ce-MOF in water-vapor induced power generation, and provides a new strategy for electrochemical detection. The constructed light-assisted water-vapor self-powered sensor has a wide detection range, high sensitivity, low detection limit and low detection cost.

The invention discloses a preparation method of an addressable disc ultramicro electrode array for electrochemical imaging, which comprises the following steps of: 1, preparing a nanowire array by using an ultrathin slicing machine as processing equipment and a silicon wafer with a micron groove array structure as a template; 2, transferring the nanowire array to a silicon wafer, performing three-dimensional alignment on a molybdenum mask plate with a lead pattern and the nanowire array, and realizing lap joint of a lead and the nanowire array and preparation of the lead by combining a physical vapor deposition method; 3, resin is poured on the silicon wafer for normal-temperature curing, and the pattern is transferred to the resin; 4, macroscopic wire lap joint and packaging are carried out, a resin block with an embedded array structure is obtained, the end face is trimmed through an ultra-thin slicing machine, the dot array is exposed, and preparation of the addressable disc ultramicro electrode array is completed. According to the method, the addressable disc ultramicro electrode array which is high in consistency, high in spatial resolution and capable of being expanded at will can be prepared simply and efficiently at low cost.

The invention relates to the technical field of contact lenses, in particular to a self-driven sensing contact lens with an intraocular pressure monitoring function and a preparation method of the self-driven sensing contact lens. Comprising a lens, a sensing assembly, an electrode structure and a monitoring characterization module, the sensing assembly comprises a silicon substrate and a nanowire array arranged on the upper surface of the silicon substrate, the nanowire array comprises a plurality of nanowires arranged at intervals, each nanowire is perpendicular to the upper surface of the silicon substrate, and the electrode structure is arranged on the upper surface of the silicon substrate. The sensing assembly is used for generating a water volt electric signal related to deformation when the silicon substrate is deformed; the electrode structure comprises a first electrode plate arranged between the sensing assembly and the inner side of the lens and a second electrode plate adhered to the side, away from the lens, of the sensing assembly. The self-driven sensing contact lens has high sensitivity and good biocompatibility, can comprehensively and continuously capture tiny shape changes of eyeballs in different states, and provides richer and more accurate data support for intraocular pressure monitoring.

The invention relates to a P-doped MoS2 / Co4S3 and CoP heterojunction hollow nanotube array electrode as well as a preparation method and application thereof, and belongs to the field of new energy materials such as water electrolysis and metal-air batteries. The preparation method comprises the following steps: firstly, placing a pretreated substrate material in a mixed solution of cobalt salt, urea and ammonium fluoride, and preparing a Co (OH) 2 nanowire array electrode through a high-temperature hydrothermal method; secondly, the electrode is placed in an ammonium tetrathiomolybdate solution, and a precursor is obtained through secondary high-temperature hydrothermal treatment; and finally, pyrolyzing the electrode and sodium hypophosphite in a high-temperature tubular furnace together to obtain the P-doped MoS2 / Co4S3 and CoP heterojunction hollow nanotube array electrode. The prepared electrode material has the advantages of low cost, high activity, good stability and the like, and has wide application prospects in the fields of water electrolysis, metal-air batteries, domestic sewage treatment and the like.

The present invention discloses a self-driven double-heterojunction photodetector based on a silicon nanowire array and its preparation method. From top to bottom, the structure consists of a PEDOT:PSS top electrode (treated with ethylene glycol), a PbSe quantum dot film layer, a ZnO bulk material film layer, a silicon nanowire array layer, and a silicon bottom electrode. The ethylene glycol-treated PEDOT:PSS significantly enhances its conductivity, making it a transparent electrode for the device and reducing incident light loss. The PbSe / ZnO and ZnO / Si-NWA double heterojunctions broaden the device's spectral response range and accelerate the separation of photogenerated excitons. The silicon nanowire array structure reduces incident light reflection. Furthermore, the introduction of the ZnO film significantly reduces dark current compared to the previous simple Si-NW / PbSe structure. This structure can effectively improve the detection performance of silicon-based photodetectors.

The invention discloses a terahertz detector based on a Dirac semimetal nanowire structure, and particularly relates to the terahertz field, the terahertz detector comprises a gold reflecting layer, a dielectric layer and a Dirac semimetal material layer, the dielectric layer is arranged on the top of the gold reflecting layer, and the Dirac semimetal material layer is arranged on the top of the dielectric layer; and the Dirac semi-metal material layer is a Dirac semi-metal nanowire array layer. A Dirac semimetal-silicon dioxide-gold three-layer structure is adopted, Fano resonance and F-P resonance are excited to be coupled through a nanowire array, high absorption (99.02% at most) of seven frequency bands within the range of 0-14.5 THz is achieved, dynamic tuning is achieved by adjusting the Fermi level of Dirac semimetal, the sensitivity reaches 5421.43 GHz / RIU, the quality factor is 35.204 (1 / RIU), and the device is stable in structure, easy to process and suitable for large-scale production. The device is suitable for the fields of terahertz detection, imaging, biosensing and the like.

This invention discloses a method for preparing cobalt-manganese sulfide nanosheets@cobalt-copper sulfide nanowire arrays / nickel foam as a supercapacitor electrode material. The purpose of this invention is to design a core-shell structure composed of different components to improve the specific capacity and cycle performance of the electrode material. This invention mainly includes: 1. Hydrothermal preparation of cobalt-copper precursor / nickel foam (CoCu-pre / NF); 2. Hydrothermal sulfidation preparation of cobalt-copper sulfide nanosheet arrays / nickel foam (CuCo2S4 / NF); 3. Hydrothermal preparation of cobalt-manganese sulfide nanosheets@cobalt-copper sulfide nanowire arrays / nickel foam (MnCoS@CuCo2S4 / NF). This invention features a simple synthesis process, low cost, high yield, and no need for subsequent processing. The MnCoS@CuCo2S4 heterostructure exhibits stronger OH... ‑ The MnCoS@CuCo2S4 / NF electrode exhibits high capture capacity and excellent conductivity, thereby enhancing the efficiency of rapid redox processes. At 1 A g... ‑1 At that time, it obtained 1141.2 C g. ‑1 The specific capacitance at 10 A g ‑1 It exhibits excellent cycling performance of 90.7% over 10,000 cycles. (740.47 W kg) ‑1 At a power density of 64.38 Wh / kg, the hybrid supercapacitor (HSC) can provide 64.38 Wh / kg. ‑1 The electrode exhibits high energy density and can successfully light up LED bulbs. It has enormous application potential as a high-performance electrode material for supercapacitors.

The application discloses a spectrum shift type hydrogen sensor and a preparation method thereof, and comprises a silicon substrate, a suspended micro-bridge formed by local etching and releasing of the silicon substrate, and a nanowire array arranged on the suspended micro-bridge, wherein the nanowire sensitive structure in the nanowire array comprises, from inside to outside, a gold core, a palladium shell layer coated on the periphery of the gold core, an air gap located outside the palladium shell layer, an annular gold shell layer arranged around the air gap, and a porous alumina filling layer reserved in the final device and filled outside the annular gold shell layer; a temperature control circuit is connected with the suspended micro-bridge and used for controlling the working temperature of the suspended micro-bridge; wherein the nanowire sensitive structure is subjected to plasmonic resonance spectrum peak displacement under the action of hydrogen, and the air gap and the annular gold shell layer form a radial coupling cavity for amplifying the readout amplitude of the spectrum peak displacement. The application can realize high-sensitivity, fast-recovery and high-stability hydrogen spectrum detection.

The invention belongs to the technical field of ultraviolet photoelectric detection, and relates to a self-supporting SiC / GaN heterojunction nano array applied to underwater optical communication and a preparation method and application thereof. The GaN thin layer is successfully loaded on the surface layer of the self-supporting SiC nanowire array, and the original nanowire array structure is not influenced, so that the photo-anode has a relatively large specific surface area, the photo-anode is facilitated to absorb more photons and generate more electron-hole pairs, and the photoelectric conversion efficiency of the photo-anode is improved. And the highly-ordered nanowire array structure also provides a larger solid-liquid reaction interface, so that the electrode reaction is promoted.

A vertical cavity surface emitting laser, and a preparation method therefor. The preparation method comprises: S1: providing a substrate (10); S2: sequentially growing on the substrate (10) a buffer layer (20), an N-type DBR (30), an N-spacer layer (40), a multi-quantum well layer (50), a P-spacer layer (60), a thin layer (70) and a first P‑GaAs layer (81); S3: growing a plurality of parallel AlAs nanowires (82); S4: growing a second P‑GaAs layer (83) on the AlAs nanowires (82); S5: repeating S3-S4 so as to form a P-type DBR, wherein the P-type DBR comprises the first P‑GaAs layer (81), the AlAs nanowires (82) and the second P‑GaAs layer (83); S6: etching the P-type DBR to form a plurality of columnar structures; S7: using an HF solution to corrode the AlAs nanowires (82), so as to obtain a plurality of linear cavities (84); and S8: depositing a first electrode (91) and a second electrode (92), so as to obtain a vertical cavity surface emitting laser. In the preparation method, a nanowire array structure is prepared by means of laser-induced thin film deposition, and in combination with a selective corrosion process, the dependence on growth processes and devices can be reduced, thereby lowering the process barrier, improving the preparation efficiency and achieving low production costs.

The application discloses a method for synthesizing Au-Pt nanowire arrays by an electrochemical deposition method on carbon paper with aniline as a ligand and application thereof, and can be applied to methanol electro-oxidation reaction. After growing gold nanowire arrays on a conductive substrate by using an electrochemical deposition method with aniline as a ligand, Au-Pt nanowires are synthesized by a secondary electro-deposition mode. The electrochemical deposition has controllable reduction capacity, convenient operation and environmental friendliness. The combination of gold nanowires and platinum (Pt) can significantly improve the activity of a catalyst. The diameter of gold-platinum nanowires prepared by the electrochemical deposition method assisted by an aniline ligand can reach 30 nanometers. The increase in the size is helpful to expand the electrochemical active surface area, thereby enhancing the electron transmission efficiency and further improving the electro-catalytic performance. The gold nanowires are integrated into platinum-based nanomaterials, and for an anode catalyst of a direct methanol fuel cell, the gold nanowires can significantly improve the catalytic efficiency of a methanol oxidation reaction.

The invention discloses a gold nanoparticle modified ordered crossed tungsten oxide nanowire array material, which is characterized in that gold nanoparticles are uniformly distributed on the surfaces of tungsten oxide nanowires, and the plasmon effect of the gold nanoparticles is utilized to enhance the gas-sensitive property, so that the gas-sensitive property is improved. The gold nanoparticle modified ordered crossed tungsten oxide nanowire array material can be applied to a gas sensor, active sites can be increased, the gas sensitivity of the material can be improved, the working temperature can be reduced, the energy consumption can be reduced, the sensitivity of recognizing 50ppm NO2 gas at the optimal working temperature under three sunlight intensities can reach 606.8, and the recovery time and the response time are 20s and 81s respectively.

This invention relates to a silicon nanowire array accelerometer with an adjustable optimal operating point and its fabrication method. The silicon nanowire array accelerometer includes silicon nanowire sensing elements, a mass block, a silicon nitride thin film, a gold electrode, a gate, and a silicon substrate. When the accelerometer is subjected to external acceleration, the up-and-down movement of the mass block causes deformation of the silicon nanowires, resulting in changes in the conductivity of the silicon nanowires and thus outputting a changing signal. Simultaneously, the gate of this invention can modulate the silicon nanowire channel, thereby finding the optimal operating point of the device. Furthermore, the gate structure effectively protects the silicon nanowires from breakage due to various reasons, greatly improving the long-term stability of the silicon nanowire device. The fabrication method of this invention is simple, low-cost, and can be mass-produced.

The invention provides an MEMS gas sensor and a preparation method thereof. The MEMS gas sensor comprises an insulating substrate, a heating electrode, an insulating layer and a test unit which are stacked, the test unit comprises a test electrode, a sensitive unit and a selective separation membrane; the sensitive unit is provided with a nanowire array structure formed by a plurality of nanowires arranged at intervals, and the selective separation film covers the surfaces of the sensitive unit and the concave part; wherein the nanowire comprises a first metal and a second metal, the first metal is Pd, and the second metal is selected from at least one of Ni, Cu, Ag, Au and Ir; the selective separation membrane comprises an inner-layer separation membrane and an outer-layer separation membrane which are sequentially stacked; the inner-layer separation membrane comprises polytetrafluoroethylene; the outer-layer separation membrane is a mixed matrix membrane which takes a covalent organic framework material as a filler and takes an intrinsic microporous polymer as a matrix. The MEMS gas sensor has excellent low-concentration gas monitoring sensitivity, high-concentration gas tolerance stability and excellent anti-interference performance and response speed.

This invention relates to the field of diamond heat sinks, specifically a diamond heat sink and its preparation method, comprising: in-situ growth of a silicon carbide nanowire array on a diamond surface; sputtering a titanium carbide layer on the diamond surface using magnetron sputtering to obtain a titanium carbide / silicon carbide nanowire array composite structure; placing solder paste between the diamond and a metal sheet to form a brazed component, wherein the titanium carbide / silicon carbide nanowire array composite structure in the brazed component faces the side of the solder paste; and finally vacuum brazing. This invention has good process compatibility, is easy to realize industrial application, and effectively solves the problems of weak interface bonding, high thermal stress, and high interface thermal resistance when connecting diamond films and metals. It has important application value for heat dissipation of high-power electronic devices.