43 results about "Silicon quantum dots" patented technology

The invention discloses a silicon-carbon composite negative electrode material and a preparation method thereof, the silicon-carbon composite negative electrode material comprises a core-shell active unit, a conductive network layer and a composite coating layer, the core-shell active unit is a structure formed by loading boron-doped silicon quantum dots in hollow carbon spheres; the composite material is prepared from the following components in percentage by mass: 11 to 18 weight percent of boron-doped silicon quantum dots, 24 to 36 weight percent of hollow carbon spheres, 31 to 42 weight percent of polyimide-derived nitrogen-doped carbon nanofibers, 3 to 8 weight percent of fluorophosphate-aluminum oxide composite coating layer and 2 to 5 weight percent of lithium titanate modified montmorillonite, the mass ratio of fluorophosphate to aluminum oxide in the fluorophosphate-aluminum oxide composite coating layer is 3: 1, the particle size of the boron-doped silicon quantum dots is 2-5nm, the doping amount of the boron element is 1-3at%, and the purity is not lower than 99.95%. The core-shell structure is used for buffering silicon expansion, the nitrogen-doped carbon fiber is used for constructing a high-efficiency conductive network, the composite coating layer is used for stabilizing an interface, and the inorganic dispersed phase is used for inhibiting agglomeration, so that the specific capacity, the cycling stability and the first charge-discharge efficiency of the lithium ion battery are remarkably improved.

A nanophotonic scale inhibitor includes a silicon quantum dot core having a functionalized surface including a plurality of carboxyl groups, sulfonate groups, or phosphonate groups. A method for synthesizing a nanophotonic scale inhibitor material includes preparing silicon quantum dots for surface functionalization and functionalizing surfaces of the silicon quantum dots with one of a carboxyl group, sulfonate group, and phosphonate group. A method of inhibiting and monitoring scale formation in water systems includes providing the nanophotonic scale inhibitor to the water in the water system and visualizing scale formation by detecting fluorescence of the nanotphotonic scale inhibitor.

This invention provides a silicon quantum dot modified composition, modified silicon quantum dots, a thickener, a thickener system, drilling fluid, and completion fluid. The silicon quantum dot modified composition comprises an organic solvent and two modifying agents. When the silicon quantum dots obtained by further modification of this silicon quantum dot modified composition are used as thickeners in high-salinity drilling and completion fluids, the thickener exhibits excellent high-temperature resistance and continues to provide good rheological and thixotropic properties even after aging.

PPAB derived near-infrared super-small fluorescent silica nanoparticles and synthesis method and application thereof, the fluorescent silica nanoparticles prepared by the present application exhibit strong near-infrared fluorescence and good water solubility, have a strong fluorescence emission peak near 650 nm-700 nm wavelength, exhibit good fluorescence spectrum performance, and therefore the silicon quantum dots have relatively good cell tissue penetration. Due to the unique optical properties and relatively good cell tissue penetration, the in vivo fluorescence imaging can be effectively carried out. The fluorescent silica nanoparticles prepared by the present application have excellent singlet oxygen generation performance and peroxidase performance in addition to excellent near-infrared optical performance and good biocompatibility, can be used as a photodynamic / chemodynamic synergistic treatment reagent, and are used for antibacterial and antitumor applications, and have no toxic side effects on the organism itself.

The application discloses a kind of ratio fluorescent sensor based on smart phone and its preparation method and application, the preparation method includes: after mixing chloroauric acid, bovine serum albumin, sodium hydroxide, gold cluster reaction liquid is obtained;Sodium citrate, 3-aminopropyl triethoxysilane, glycerol are mixed to obtain silicon quantum dot solution;Silicon quantum dot solution, lipopolysaccharide aptamer, EDC, NHS are reacted in ultrapure water to obtain aptamer modified silicon quantum dots;Lipopolysaccharide aptamer modified silicon quantum dots and gold cluster are mixed to obtain ratio fluorescent sensor.The ratio fluorescent sensor based on smart phone prepared by the application has good stability, strong specificity, can exclude fluorescent interference in environmental matrix, and is used for lipopolysaccharide analysis and detection by combining the colorimetric analysis of color picker of smart phone, so that in-vitro naked-eye visible rapid quantitative detection of lipopolysaccharide can be realized, to meet the demand of on-site monitoring.

The present invention belongs to the field of optical communications technology, specifically a high-brightness, communication-band silicon-based luminescent film doped with a high concentration of erbium and a method for preparing the same. The present invention uses HSQ as a solvent and erbium nitrate pentahydrate as a source of erbium. Ytterbium ions and independent silicon quantum dots are co-doped, stirred, spin-coated, and subjected to high-temperature annealing to obtain a high-brightness erbium-doped silicon-based luminescent film. HSQ photoresist is used as a precursor material for the preparation of silicon nanocrystal films. After being doped with erbium and subjected to high-temperature annealing, the resulting film contains a large amount of silicon nanocrystals. The silicon nanocrystals act as sensitizers in the energy transfer process, absorbing incident photon energy and then transferring and activating erbium ions to achieve photoluminescence with a central emission wavelength of 1.54 μm. The present invention avoids the numerous defects associated with ion implantation and eliminates the need for maintaining a high vacuum. The resulting erbium-doped film has a high concentration of silicon nanocrystals, which act as erbium luminescence sensitizers, and is simple to prepare and safe to operate.

According to the graphene-enhanced silicon-carbon negative electrode material and the preparation method thereof, the graphene-enhanced silicon-carbon negative electrode material comprises the following components in percentage by mass: 80-90% of a graphene substrate and 10-20% of silicon quantum dots, the surface of the graphene substrate is provided with a defect aperture and three-dimensional gradient pore channel structure, and the surface of the silicon quantum dots is provided with the defect aperture and the three-dimensional gradient pore channel structure. And the silicon quantum dots grow in the defect apertures in situ. The preparation method of the graphene enhanced silicon-carbon negative electrode material comprises the following steps: S1, pretreatment of a graphene substrate; S2, deposition of silicon quantum dots; S3, interface covalent bonding reinforcement; and S4, construction of a three-dimensional gradient pore channel. Through organic coupling of graphene substrate pretreatment, silicon quantum dot in-situ growth, interface covalent bonding reinforcement and a three-dimensional gradient pore channel construction technology, a synergistic system of structural design-interface regulation and control-performance optimization is formed, and the problems of size mismatch of graphene and silicon particles, weak interface acting force and poor dispersity are solved.

The invention discloses a preparation method of a silicon quantum dot-Fe < 3 + > fluorescent probe and application of the silicon quantum dot-Fe < 3 + > fluorescent probe in detection of glyphosate pesticide residues, belongs to the field of analytical chemistry, and solves the problems that an existing detection method is long in detection time consumption, complex in sample pretreatment and difficult in high-throughput analysis. The preparation method comprises the following steps: introducing a newly prepared sodium ascorbate solution and a 3-aminopropyltrimethoxysilane solution into ultrapure water for reaction; dialyzing the solution in distilled water to remove unreacted solvent, and storing the obtained solution in a dark place at room temperature; carrying out rotary evaporation on the solution until the solution is viscous, pumping by a vacuum pump until the solution is dry, and dissolving by distilled water to obtain a silicon quantum dot solution; and incubating the silicon quantum dot solution and Fe < 3 + > at room temperature to form the silicon quantum dot-Fe < 3 + > fluorescent probe. The preparation method is simple, and reaction products are easy to separate and purify; the method is simple and convenient in glyphosate detection operation, good in selectivity, rapid in response and high in sensitivity, and can be used for rapid and quantitative detection of glyphosate pesticide residues in vegetables.

The invention relates to the technical field of intelligent cables, and discloses an intelligent temperature monitoring wire, which comprises a conductor core, an insulating layer, a shielding layer and a protective sleeve, the insulating layer is made of a temperature-sensitive composite material, a temperature sensor array is uniformly distributed in the insulating layer, and each temperature sensor is connected to a data processing device through a conductor wire; the data processing device is integrated at the end part of the electric wire and comprises a signal acquisition module, a temperature resolving module and a communication module; the temperature-sensitive composite material comprises the following components in percentage by mass: 68-72% of polyvinylidene fluoride; the silicon carbide quantum dots are 24-26%, the particle size is 2-4 nm, and the surface amino silane grafting density is 3.8-4.5 molecules / nm < 2 >; the length-diameter ratio of the graphene nanobelt is greater than or equal to 1000; 3.5-4.5% of hexagonal boron nitride, and the thickness of the hexagonal boron nitride is 1t; 5 nm. Through the technical scheme of the spiral arrangement of the graphene nanobelts and the synergistic effect of the quantum dots, the rapid and accurate capture of the temperature change is realized, so that the temperature monitoring result is closer to the real working condition.

The invention relates to the technical field of battery electrode materials, in particular to a high-cyclicity battery negative electrode material and a preparation method thereof, and the high-cyclicity battery negative electrode material comprises a core body and a shell layer; the core body is a metal organic framework derived porous carbon matrix, silicon quantum dots are loaded in three-dimensional channels of the matrix, and the silicon quantum dots are combined with the porous carbon matrix through Si-O-C covalent bonds; the shell layer is a dynamic cross-linked polymer coating coated on the surface of the core body, and the coating is formed by dynamically cross-linking oxidized polyvinyl alcohol and dopamine through a Schiff base bond. A core-shell structure is constructed, silicon quantum dots are loaded by porous carbon three-dimensional channels, Si-O-C bonds are formed, and the surface is coated with a dynamic cross-linked polymer coating. According to the structure, through dynamic reversible characteristics of covalent bonding and Schiff base bonds, multi-stage buffering of uniform dispersion and volume expansion of the silicon quantum dots is realized, so that the capacity retention rate of the battery is greater than or equal to 90% and the pole piece expansion rate is less than or equal to 12% after 1000 times of circulation at 1C multiplying power, and the problem of structural collapse of the silicon-based negative electrode is effectively solved.

The application discloses a graphene-reinforced silicon-carbon negative electrode material and a preparation method thereof, wherein the graphene-reinforced silicon-carbon negative electrode material comprises the following components in percentage by mass: 80-90% of a graphene base and 10-20% of silicon quantum dots; the graphene base has a defect pore size and a three-dimensional gradient pore structure on the surface; and the silicon quantum dots are in-situ grown in the defect pore size. The preparation method of the graphene-reinforced silicon-carbon negative electrode material comprises the following steps: S1, pretreatment of the graphene base; S2, deposition of the silicon quantum dots; S3, interface covalent bond strengthening; and S4, construction of the three-dimensional gradient pore. Through organic coupling of the graphene base pretreatment, the in-situ growth of the silicon quantum dots, the interface covalent bond strengthening and the three-dimensional gradient pore construction technology, a synergistic system of "structure design-interface regulation-performance optimization" is formed, and the problems of size mismatch between the graphene and the silicon particles, weak interface force and poor dispersibility are solved.

The invention belongs to the field of preparation of semiconductor nanomaterials, and provides a method for in-situ synthesis of hydrophilic-hydrophobic adjustable p-n type silicon quantum dots, which comprises the following steps: S1, slowly dropwise adding a mixed solution of tetraethoxysilane and a p type doped-hydrophilic regulating agent into a basic reaction solution in an alkaline hydrolysis environment, and stirring to obtain a mixed solution; stirring and reacting in an oil bath at a first temperature for more than 1 hour to form a boron-doped p-type silicon quantum dot core layer; s2, heating to a second temperature, adding a mixed regulating agent of an n-type doped-hydrophobic regulating agent and dodecyltrimethoxysilane, and continuing to react for 2-4 hours; and S3, after the reaction in the step 2 is finished, adding isopropanol accounting for 1 / 3 of the volume of the residual reaction liquid, centrifugally collecting the precipitate, and purifying the precipitate by adopting a biphase purification method to obtain the p-n type silicon quantum dots. By adjusting the molar ratio of B-TEOS / P-TEOS and the addition amount of DTMS, gradient regulation and control of p-n type doping concentration and contact angle can be realized.

The invention relates to the technical field of crystalline silicon solar cells, and discloses a method for improving the double-sided rate of a photovoltaic cell and the photovoltaic cell. The method comprises the following steps: preparing a doped silicon quantum dot composite layer on the back surface of a pretreated silicon wafer; wherein the back surface of the silicon wafer is divided into a back surface metallization region and a back surface non-metallization region, and a plurality of mutually separated spacer regions are arranged in the back surface non-metallization region; carrying out local film opening treatment on the back surface of the silicon wafer to remove the doped silicon quantum dot composite layer in a back surface grid line contact region; and carrying out dot matrix film opening treatment on the back surface of the silicon wafer, and removing the doped silicon quantum dot composite layer in the spacer region by using a dot matrix to obtain a plurality of locally doped silicon quantum dot structures which are distributed at intervals. The method can effectively avoid the risks that series resistance is increased, contact is poor, and carriers are difficult to penetrate through an insulating material to form effective carriers and the like caused by a multi-layer silicon quantum dot structure prepared in the prior art, and the back light absorption capacity and the double-sided rate of the cell are further improved.

The invention relates to an anti-dazzle coating liquid and an optical film applying the anti-dazzle coating liquid, the anti-dazzle coating liquid contains modified high-refractive-index anti-dazzle particles, the modified high-refractive-index anti-dazzle particles comprise organic particles attached with silane coupling agent grafted silicon carbide quantum dots, after the anti-dazzle coating liquid is prepared into a coating, the modified high-refractive-index anti-dazzle particles can form a micro-coarse structure in the coating, the proper thickness is combined, and the anti-dazzle effect is good. Light rays can be efficiently scattered, so that the anti-dazzle grade of the coating reaches up to LV6, and good anti-dazzle performance is guaranteed. Meanwhile, the coating prepared from the anti-dazzle coating liquid is combined with the low-refractive-index coating for use, so that the refractive index of the low-refractive-index coating does not need to be further reduced, the destructive interference of light can be realized, the reflectivity of the optical film is reduced to be less than 1%, the total haze of the coating can be controlled to be less than 2%, and the overall hardness and wear resistance of the optical film are improved.

This application relates to a food freshness indicator label and its preparation method, comprising waterborne polyurethane, carbon quantum dots, silicon quantum dots, a film-forming agent, and water. The indicator label of this application uses carbon quantum dots and silicon quantum dots as composite freshness indicators, which are characterized by low toxicity and good stability. The carbon quantum dots and silicon quantum dots specifically bind and react with volatile substances produced by food spoilage, causing changes in fluorescent color, thereby reflecting the freshness of the food in real time. It has the advantages of sensitive response, low production cost, and mass production. Compared with single-component indicators, the composite indicator of this application has the characteristics of a wide detection range and adaptability to a wide range of conditions, making it an economical and practical smart food freshness indicator label.

This invention discloses a dual-emission silicon quantum dot, its preparation method, and its applications, belonging to the fields of chemistry and nanomaterials science. The present invention uses 3-aminopropyltrimethoxysilane and oreganoic acid as reaction precursors to prepare dual-emission fluorescent silicon quantum dots via a one-step hydrothermal method. Using the technical solution of this invention, dual-emission silicon quantum dots can be prepared in a single hydrothermal reaction, making the synthesis method simple, using readily available raw materials, and inexpensive. The dual-emission silicon quantum dots prepared by this invention exhibit good photostability, low cytotoxicity, and two fluorescence emission peaks, displaying distinct blue and green dual-channel fluorescence in MCF-7 cells, showing potential applications in cell imaging.

The invention discloses a method for detecting pyrethroid by using silicon fluoride quantum dots, belongs to the technical field of fluorescence sensing, and designs fluorinated fluorescent silicon quantum dots (FSiQDs) for rapid and visual detection of pyrethroid. The preparation method comprises the following steps: taking fluorophenylhydrazine and N-(beta-aminoethyl)-gamma-aminopropyltrimethoxysilane (DAMO) as raw materials, and reacting at 175-225 DEG C for 4-9 hours to obtain the fluorophenylhydrazine-gamma-aminopropyltrimethoxysilane. Under excitation of 300-400 nm, the fluoro-functionalized silicon quantum dot fluorescent probe emits blue fluorescence (450 nm), fluorescence quenching occurs after the blue fluorescence reacts with pyrethroid hydrolysate 3-phenoxybenzaldehyde (3-PBD), and the quenching rate reaches 75%. The probe has high selectivity and has no interference on common pesticides, metal ions and biomolecules.

The invention discloses high-brightness liquid and solid orange-red light silicon quantum dots as well as a preparation method and application thereof, and belongs to the technical field of chemistry and fluorescent material science. The raw materials are subjected to a one-pot hydrothermal reaction in a water phase to directly prepare the high-brightness liquid-state and solid-state orange-red light silicon quantum dots. Through the mode, the high-brightness liquid-state and solid-state orange-red light silicon quantum dots with excellent luminescence performance and high fluorescence quantum yield can be prepared.

The invention provides a preparation method of a phenylboronic acid functionalized silicon quantum dot fluorescent probe and application of the phenylboronic acid functionalized silicon quantum dot fluorescent probe in detection of mercury ions and methyl mercury ions, and relates to the technical field of detection of heavy metal mercury ions and methyl mercury ions. In the presence of mercury ions (Hg < 2 + >) and methyl mercury ions (CH3Hg < + >), silicon point fluorescence is quenched. By combining ultraviolet portable equipment and combining a silicon puncture-Hg < 2 + > and silicon puncture-CH3Hg < + > system with RGB value acquisition and conversion of a smart phone platform, rapid and high-sensitivity detection of mercury ions and methyl mercury ions in an environmental water body is realized. The detection method disclosed by the invention has the advantages of simplicity and convenience in operation, rapid feedback, high sensitivity, good repeatability, high stability, strong accuracy and the like, can intuitively realize rapid determination of mercury ions and methyl mercury ions in a water sample in real time, and widens the application direction of silicon dots in the aspect of environmental detection.

The invention discloses a design and detection method of a functional modified silicon quantum dot (SiQDs) fluorescent sensor, belongs to the technical field of environmental pollutant detection, and is characterized in that fluorescent silicon quantum dots containing hydrazino functional groups are prepared by doping phenylhydrazine derivatives when traditional silicon quantum dots are prepared. Meanwhile, fluorescent silicon quantum dots with the emission wavelength of 400-700 nm can be prepared by adding different types of fluorescent dyes. The silicon quantum dot has good luminescence property and stability, and especially has good response capability when being used for detecting a pyrethroid hydrolysate 3-phenoxybenzaldehyde.

The present invention relates to a silicon quantum dot crosslinking agent for a jelly-type plugging agent and a preparation method thereof, belonging to the technical field of oilfield chemistry. Silicon quantum dots are modified by a modifier containing epoxy and siloxane structures to prepare epoxy silicon quantum dots. On this basis, epoxy silicon quantum dots are modified by a modifier containing amino, polyoxyethylene and dicarboxymethylimino structures to prepare silicon quantum dots with multiple functional groups on the surface. Test results show that at low concentrations, the modified silicon quantum dots can well crosslink acrylamide polymers, and the prepared jelly has high strength and good anti-aging ability under high temperature and high salinity conditions. The jelly crosslinking agent prepared by the present invention has broad application prospects in high-temperature oil reservoir profile control and water plugging.

The invention relates to the technical field of preparation of silicon-based quantum dot tracers, and particularly discloses a silicon-based quantum dot tracer for oil and gas exploitation and a preparation method thereof.The silicon-based quantum dot tracer comprises an inner core, a shell and a reinforcing agent, the inner core is silicon quantum dots, the shell is a modified layer, the modified layer is formed by a copolymer of sulfur-containing organosilane and fluorine-containing organosilane, and the reinforcing agent is a silicon quantum dot / fluorine-containing organosilane copolymer. The molecular structure of the sulfur-containing organosilane contains sulfydryl or thioether bonds, the molecular structure of the fluorine-containing organosilane contains at least three fluorine atoms, the reinforcing agent is rare earth ion doped titanium dioxide nanoparticles, the rare earth ions are europium ions, terbium ions or neodymium ions, and the doping amount is 2% of the mass of the titanium dioxide nanoparticles. According to the silicon-based quantum dot tracer agent for oil and gas exploitation and the preparation method thereof, the toxicity problem of heavy metal quantum dots is avoided, environment-friendly raw materials and processes are adopted in the preparation process, the green development concept of oil and gas fields is met, and the pollution risk to stratums and the environment is reduced.

The application provides a preparation method of a silicon quantum dot water treatment agent with corrosion and scale inhibition performance, wherein trimethylsilicon imidazole is used as a silicon source, carboxymethyl cellulose is used as a modifier, and trisodium citrate is used as a reducing agent, which are dispersed in ultrapure water, and then stirring is performed to obtain a mixed solution; the obtained mixed solution is transferred to a reaction container for heating reaction, and a silicon quantum dot solution is obtained; the silicon quantum dot solution is centrifuged, and then purified and dried to obtain a solid silicon quantum dot water treatment agent. The silicon quantum dot water treatment agent can be applied to carbon steel under neutral and acidic conditions to achieve the purpose of corrosion inhibition, and can effectively inhibit calcium scale in a solution prone to forming calcium sulfate scale and calcium carbonate scale.

The invention provides a solar cell, a preparation method thereof and a photovoltaic module. The solar cell comprises a substrate, wherein a passivation layer, a first silicon nitride layer and a second silicon nitride layer are sequentially stacked on the surface of one side of the substrate; wherein silicon quantum dots are doped and distributed in the first silicon nitride layer. According to the invention, the silicon quantum dots with down-conversion capability are introduced into the first silicon nitride layer, and UVB is converted into visible light or UVA which can be efficiently utilized by the cell by utilizing the down-conversion characteristic of the silicon quantum dots, so that the loss of photoelectric efficiency is reduced while UVB protection is realized, the dependence on a special ultraviolet cut-off material is reduced, and the production cost is further reduced. Therefore, the first silicon nitride layer is used as a functional core layer to cooperate with the second silicon nitride layer, so that the long-term stability of the down-conversion performance of the first silicon nitride layer is protected, the down-conversion gain effect of the first silicon nitride layer is enhanced, the passivation effect on the substrate is enhanced, and the carrier recombination loss is reduced.

The present invention belongs to the field of printing coating technology and specifically provides an environmentally friendly, high-gloss water-based ink and a preparation method thereof. The water-based ink comprises the following components by weight: 40-50 parts of a water-based acrylic resin, 5-10 parts of a fluorinated polyurethane resin, 2-4 parts of an environmentally friendly surfactant, 2-5 parts of a pigment, 2-4 parts of an antioxidant, 4-6 parts of biomass graphene, 0.5-1 part of a silicon quantum dot solution, 2-4 parts of sodium alginate, 4-6 parts of triethylamine, and 30-40 parts of distilled water. The present invention utilizes biomass waste to prepare graphene materials, which are combined with silicon quantum dots to enhance the gloss of the water-based ink. Furthermore, environmentally friendly sodium alginate is used as a thickener to precisely control the viscosity of the water-based ink. The synthetic raw materials do not contain harmful ingredients. This innovative technology injects new impetus into environmentally friendly printing and sustainable development.

The application discloses a kind of high-pressure polarization quantum dot electrode preparation process without attenuation, belongs to energy storage electrode preparation technical field.The process includes five core steps of quantum dot pretreatment, electrode coating, drying, two-way differentiation polarization, post-processing, by surface pretreatment to carbon quantum dots and silicon oxide quantum dots, optimize coating process, adopt two-way differentiation polarization of accurate temperature control, control field, combined with post-processing solidification, prepare anode polarization carbon quantum dot positive electrode and cathode polarization silicon oxide quantum dot negative electrode.The polarization quantum dot electrode prepared in the application has strong charge trap stability, non-decay charge density, complete electrode structure, no cracking, falling phenomenon when working in the range of 0.1V to infinite high voltage, adapts to infinite high-voltage energy storage device, solves the technical pain points of existing polarization electrode performance attenuation under high pressure, structure damage.

The invention discloses a co-condensed silicon quantum dot oil-displacing agent as well as a preparation method and application thereof, and belongs to the technical field of petrochemical engineering. The preparation method comprises the following steps: dropwise adding dodecyltrimethoxysilane into an acidic mixed solution of water and ethanol, and stirring at normal temperature for pre-hydrolysis to obtain a silanol solution; the preparation method comprises the following steps: mixing a silanol solution with 3-aminopropyltrimethoxysilane, heating under the protection of nitrogen, carrying out a hydrothermal condensation reaction to form a silicon quantum dot oligomer, and sequentially cooling, dialyzing and freeze-drying to prepare functionalized silicon quantum dot powder; and dissolving the functionalized silicon quantum dot powder in deionized water, and carrying out ultrasonic treatment to obtain the co-condensed silicon quantum dot oil-displacing agent. The oil-displacing agent shows excellent surface activity, the quantum dots have the characteristic of high temperature resistance and have good stability, the raw materials are easy to obtain, methanol is generated by side reaction, no harmful gas is generated, and the preparation method is an environment-friendly preparation scheme.

The invention discloses a silicon carbide ohmic contact preparation method, an ohmic contact structure and a silicon carbide device.The silicon carbide ohmic contact preparation method comprises the steps that a silicon carbide substrate with an epitaxial layer is provided, the exposed surface of the epitaxial layer is a first surface, and the exposed surface of the substrate is a second surface; a heavily doped contact region is formed at a target ohmic contact position of the first surface and / or the second surface; forming a silicon-rich amorphous silicon carbide layer on the surface of the contact region; and forming an ohmic contact electrode layer on the surface of the silicon-rich amorphous silicon carbide layer. The silicon quantum dots wrapped by the amorphous silicon carbide substrate are used for modulating the interface potential barrier between the ohmic electrode and the silicon carbide crystal, synchronous preparation of n-type and p-type silicon carbide ohmic contact is achieved, and the method has the advantages of being simple and convenient in process and high in reliability.