34 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.

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 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 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 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 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 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.

The preparation method comprises the following steps: S1, dispersing an organic silicon source in water, raising the temperature to 60-65 DEG C, dropwise adding a reducing agent after the temperature is constant, carrying out constant-temperature stirring reaction for 2-4 hours, and cooling to obtain a silicon quantum dot solution; s2, dispersing a silane coupling agent into a mixed solution of ethanol and water, adding the dispersion solution into the silicon quantum dot solution, stirring and reacting for 3 hours, and finally dialyzing and purifying to obtain modified silicon quantum dots; s3, dissolving a surfactant in water, adding limonene into the water solution, stirring, and treating by using a high-pressure homogenizer to obtain a limonene emulsion; s4, the modified silicon quantum dots and limonene emulsion are mixed and stirred, then a high-pressure homogenizer is used for treatment, and the nanometer oil displacement agent is obtained. According to the nano oil displacement agent, the characteristics that the silicon quantum dots are small in particle size and easy to enter a small pore throat are fully utilized, the nano oil displacement agent has the effects of reducing the viscosity of crude oil, corroding organic matters in a stratum and cleaning a nano pore throat, and the oil displacement efficiency is improved through the synergistic effect of the silicon quantum dots and the nano pore throat.

The application discloses a non-volatile optoelectronic neurosynaptic device with fluorescence monitoring, comprising a gate electrode, a dielectric layer, a two-dimensional layered film, a source electrode, a drain electrode and semiconductor silicon quantum dots, wherein the dielectric layer is located on the gate electrode, the two-dimensional layered film is located on the dielectric layer, and the source electrode, the drain electrode and the semiconductor silicon quantum dot film are all located on the two-dimensional layered film, wherein the semiconductor silicon quantum dot film separates the source electrode and the drain electrode; when external light irradiates the semiconductor silicon quantum dot film, a fluorescence monitoring signal is emitted from the semiconductor silicon quantum dot film, and after the external light irradiation is removed, the non-volatility of the synaptic weight change of the optoelectronic neurosynaptic device is realized based on the change of the conductance of the two-dimensional layered film. The device can easily realize fluorescence effect and non-volatile photocurrent at the same time under the stimulation of light. The application further discloses a preparation method of the device. The preparation method is simple and efficient.

This invention discloses a water-based fast-drying anti-rust paint and its preparation process and method. The paint comprises a core-shell acrylic emulsion, an acrylic phosphate emulsion, a nano-composite zinc phosphomolybdate, nano-graphene, a phytic acid-modified silicon quantum dot composite, sodium metavanadate, and additives. It has excellent long-lasting anti-corrosion, fast-drying application, and environmental friendliness, and is particularly suitable for rust prevention and protection of steel substrates in high-chlorine corrosion environments such as marine environments.

This invention discloses a wide-voltage energy storage system based on quantum dot polarized electrets, belonging to the field of energy storage system technology. The energy storage system includes a quantum dot polarized electret energy storage unit, a series boost module, a charge / discharge control module, and a safety protection module. The quantum dot polarized electret energy storage unit consists of an anode-polarized carbon quantum dot electret positive electrode, a solid insulating layer, and a cathode-polarized silicon oxide quantum dot electret negative electrode. Stable electret charge and a built-in electric field are formed through bidirectional polarization, achieving wide-voltage energy storage. The series boost module connects multiple energy storage units in series, enabling flexible adjustment of the operating voltage from 0.1V to theoretically infinite voltage. The charge / discharge control module adjusts charge / discharge parameters, and the safety protection module ensures system safety. This invention can adapt to various high-voltage and extreme environment energy storage needs.

The invention belongs to the technical field of nano materials, and discloses a preparation method of a bismuth / silicon composite nano structure with near-infrared surface plasmon resonance characteristics. The method comprises the steps that S1, a substrate to be deposited is prepared, wherein a substrate material is selected and then cut into square blocks of 1.5 cm * 1.5 cm; s2, cleaning a to-be-deposited substrate: cleaning a deposited substrate, and ensuring structure attachment and uniformity; and S3, substrate heating, wherein the cleaned substrate is placed in a deposition cavity of a magnetron sputtering instrument. Magnetron sputtering and alternate bismuth and silicon deposition are carried out in the vacuum environment, the bismuth nanorod structure wrapping the silicon quantum dots is directly obtained, the structure replaces expensive precious metal materials such as gold and silver with relatively cheap bismuth, the manufacturing cost can be effectively reduced, the used semiconductor dielectric layer material is the most common silicon, and the semiconductor dielectric layer material is the most common silicon. The characteristics of the bismuth nanorod / silicon quantum dot composite structure are easy to regulate and control by means of doping and the like, and the formed bismuth nanorod / silicon quantum dot composite structure has obvious surface plasmon resonance characteristics in a near-infrared region.