90 results about "Bismuth selenide" patented technology

A low temperature chemical route to efficiently produce nanomaterials is described. The nanomaterials are synthesized by intercalating ions into layered compounds, exfoliating to create individual layers and then sonicating to produce nanotubes, nanorods, nanoscrolls and / or nanosheets. It is applicable to various different layered inorganic compounds (for example, bismuth selenides / tellurides, graphite, and other metal complexes, particularly transition metal dichalcogenides compounds including oxygen, sulfur, tellurium or selenium).

A fast and fully automated approach for determining the number of atomic planes in layered material samples is provided. Examples of such materials may include graphene and bismuth telluride (Bi2Te3), and materials from the bismuth selenide (Bi2Se3) samples is provided. The disclosed procedure allows for in situ identification of the borders of the regions with the same number of atomic planes. The procedure is based on an image processing algorithm that employs micro-Raman calibration, light background subtraction, correction for lighting non-uniformity, and color and grayscale image processing on each pixel of a graphene image. The developed procedure may further provide a pseudo-color map that marks the single-layer and few-layer regions of the sample. Beneficially, embodiments of the developed procedure may be employed using various substrates and can be applied to materials that are mechanically exfoliated, chemically derived, or deposited on an industrial scale.

The present invention discloses a bismuth selenide nanometer material, a preparation method and applications thereof. The preparation method comprises: dissolving a bismuth salt, a selenium-containing compound and a stabilizer in a solvent, carrying out an ultrasonic treatment, uniformly mixing, heating to a temperature of 80-200 DEG C, adding a reducing agent, cooling to a room temperature after completing a reaction, and carrying out centrifugation separation washing three times to obtain the bismuth selenide nanometer material with a diameter of 20-200 nm. The preparation method has characteristics of simple operation, less time consuming, low energy consumption and easy scalization. The prepared particles have a uniform particle size and good dispersity. With application of the bismuth selenide nanometer material as a living body X-ray CT imaging contrast agent, a significant imaging effect is provided compared with imaging effects of the traditional contrast agents such as an iodine reagent iopamidol and the like so as to provide important application prospects in the future tumor imaging field.

The invention discloses a composite nanoparticle for sensitizing tumor radiotherapy and a preparation method and application of the composite nanoparticle. The composite nanoparticle comprises proteinand bismuth selenide and manganese dioxide which grow on the protein. The preparation method comprises the steps that a manganese salt solution is added into a aqueous dispersion of bismuth selenide-protein nanoparticles, after uniform mixing is carried out, a strong alkaline solution is added, the pH value is adjusted to alkaline, a heating temperature control reaction is carried out, ultrafiltration and washing are carried out, and the composite nanoparticle is obtained. The composite nanoparticle has the advantages that the water dispersibility and biocompatibility are good, radiotherapy is sensitized by increasing the local radiation dosage through bismuth selenide and improving tumor hypoxia through manganese dioxide, and computed tomography, magnetic resonance and photoacoustic multimode imaging angiography can be achieved simultaneously; the preparation method of the composite nanoparticle is simple, convenient and practical, the condition is mild, the controllability is good,and the implementation and promotion are easy; the composite nanoparticle can achieve the integration of targeted radiotherapy sensitization, diagnosis and treatment of the tumor, and has a broad application prospect in the fields of nano-medicine, disease diagnosis, tumor treatment and the like.

The invention discloses a preparation method of few-layer bismuth selenide nanosheets, which relates to a bismuth selenide material. The preparation method comprises the following steps: putting selenium powder, bismuth oxide, polyvinylpyrrolidone, ethylene glycol and ethylenediamine tetraacetic acid into a reaction kettle to carry out a hydrothermal synthesis reaction, centrifugalizing obtained mixed liquid, removing liquid supernatant, and washing the obtained product respectively by using ultrapure water and anhydrous ethanol, and drying to obtain Bi2Se3 powder; and adding the Bi2Se3 powder into a N-methyl pyrrolidinone solvent or an acetic acid solution in which chitosan is dissolved, carrying out ultrasonic processing to obtain dispersion liquid of few-layer bismuth selenide nanosheets, standing the dispersion liquid, taking upper two thirds of the dispersion liquid and putting the taken dispersion liquid into a centrifuge to carry out low-speed centrifugalizing, collecting supernatant liquor obtained by centrifugalizing, and putting the supernatant liquor into a centrifuge to carry out high-speed centrifugalizing, removing a supernatant liquor part, and re-dispersing the obtained lower substance by using NMP (N-methyl pyrrolidinone) or an acetic acid solution, so that the few-layer bismuth selenide nanosheets dispersed in the solution are obtained finally. The preparation method is simple and quick.

The invention relates to a method for growing a bismuth selenide single crystal film on a silicon substrate. The method comprises the following steps: 1, chemically cleaning the surface of single crystal silicon and performing etching passivation to obtain the silicon substrate; 2, placing Bi2Se3 compound and the silicon substrate at a tubular furnace quartz tube center region and a first tube opening, sealing a quartz tube and vacuumizing; 3, heating the quartz tube center region; 4, introducing inert carrier gas from a second tube opening of the quartz tube to begin to grow a film; and 5, after film growth is completed, stop introducing argon and heating, introducing shielding gas to fill in the quartz tube after the temperature of the quartz tube is cooled, and then taking out a sample. The invention also relates to a device for growing the bismuth selenide single crystal film on the silicon substrate. According to the method and the device for growing the bismuth selenide single crystal film on the silicon substrate, the Bi2Se3 single crystal film is prepared on the common Si silicon substrate with a physical vapor transportation deposition device, the operation is simple, the cost is low, and the epitaxial single crystal film with high quality can be prepared.

The invention relates to a bismuth base (bismuth selenide, bismuth telluride) hydrogen storage material and a preparation method thereof, relating to low temperature liquid phase synthesis of bismuth base material and the application thereof on hydrogen storage, lithium storage and electrode material. The invention is characterized in that water is taken as solvent, bismuth salts such as bismuth nitrate, bismuth chloride and the like as a bismuth source, and water-soluble tellurium (selenium) acid salts (such as sodium tellurite, selenium substituted sodium sulfate, sodium selenite) or tellurium (selenium) acids (such as orthotelluric acid, tellurous acid and selenous acid) as a tellurium source (selenium) source; proper coordination agents (such as nitrilotriacetic acid, hexamethylene diamine tetraacethyl and the like) and reducing agents (such as vitamin C, sodium borohydride and the like) are added for liquid phase reaction synthesis at the low temperature of 60-80 DEG C. The bismuth selenide crystal grains prepared by the invention take on flower shapes with the sphere diameter of 1-6mum, and the bismuth telluride crystal grains take on sheet shapes with nanometer diameter; the hydrogen storage performance reaches over 100mAh.g. The method has the advantages of cheap raw material, simple technique, convenient operation, easy mass production, etc.

The invention relates to the field of biomedicine, in particular to a multi-functional bismuth selenide nanocomposite and a preparation method and application thereof. The multi-functional bismuth selenide nanocomposite aims to solve the problems that the synthesis condition and process of the existing hyperthermia chemotherapy nano material are complex, the biological safety is poor, the drug loading capacity is low, the existing hyperthermia chemotherapy nano material is short of an appropriate imaging diagnosis function, the heat-light properties need to be improved, and the existing hyperthermia chemotherapy nano material is short of clinical experimental verification. The grain size of the multi-functional bismuth selenide nanocomposite is 50 nm to 200 nm, and the drug loading capacity for loading doxorubicin hydrochloride is 3% to 10%. The preparation method comprises a step 1 of preparing Bi2Se3 nanosheets; a step 2 of preparing Bi2Se3@PDA nano particle dispersion liquid; and a step 3 of preparing the multi-functional bismuth selenide nanocomposite. The multi-functional bismuth selenide nanocomposite serves as the hyperthermia chemotherapy nano material to be utilized in hyperthermia chemotherapy of a malignant tumor or serves as a CT imaging contrast agent to be utilized in CT imaging diagnosis of the malignant tumor.

The invention discloses a method for obtaining abnormal linearly polarized light current of topological insulator bismuth selenide, laser passes a chopper, a polarizer and a half-wave plate in sequence, along a perpendicular bisector of a connecting line of two electrodes of a bismuth selenide sample, laser spots gradually move from the left side of the connecting line of the two electrodes to theright side according to a fixed distance, in each light spot position, the half-wave plate is rotated from 0 degree to 180 degrees, light current at each angle of the half-wave plate passes a pre-amplifier and a phase-locked amplifier, then enters a data acquisition card and is collected by a computer, fitting calculation is performed on the collected data, a relation between light current of topological insulator bismuth selenide under linearly polarized light vertical incidence in different light spot positions and the angle of the half-wave plate is obtained, and through formula fitting, abnormal linearly polarized light current in different light spot positions is extracted. The method provided by the invention is simple and is easy to realize.

The invention relates to antibody coupling bismuth selenide nanometer particles for united treatment of tumor thermal treatment and immunotherapy and a preparation method of the antibody coupling bismuth selenide nanometer particles, and belongs to the field of a pharmaceutical preparation. According to the antibody coupling bismuth selenide nanometer particles, amination bismuth selenide is usedas a carrier, PEG is used as a cross-linking agent, and a CD47 resisting antibody is coupled to the surfaces of the nanometer particles. After an antibody coupling bismuth selenide nanometer particlesuspension is intravenously injected, the nanometer particles can be massively gathered to a tumor part in a targetted manner through an EPR effect, and the condition that drug administration of the CD47 resisting antibody to whole bodies of causes anemia, is avoided. Besides, the surface-modified CD47 resisting antibody and tumor cell surfaces are high-expressed CD47 molecule specific recognition, and CD47 and SIRP alpha signal channels are closed, so that macrophages anew obtain the capacity for swallowing tumor cells. Particularly, tumor cells are subjected to thermal treatment, the residual tumor cells are eliminated by the macrophages because a signal channel free from drug administration is closed, and the purpose of thoroughly eradicating rumors is realized. The method is reasonablein design, and simple in preparation technology, has broad application prospects, and lays a foundation for design and development of a corresponding drug administration system.

The invention relates to a method for preparing a bismuth selenide micron-tablet, and belongs to the technical field of inorganic material preparation. The method comprises the following four steps: (1) preparing a spinning solution; (2) preparing a PVP / Bi(NO3)3 composite nano-fiber; (3) preparing a Bi2O3 nano-fiber, namely heating the PVP / Bi(NO3)3 composite nano-fiber; and (4) preparing a Bi2Se3 micron-tablet, namely selenizing the PVP / Bi(NO3)3 composite nano-fiber with selenium powder. The bismuth selenide micron-tablet has an excellent crystal form, belongs to the cubic system, and has a diameter of 4.46+ / -0.16mu m and a thickness of 1.57+ / -0.02mu m. The Bi2Se3 micron-tablet can be applied to the fields of thermoelectric materials, three-dimensional topping insulating materials, photo-catalysis and the like. The preparation method is simple and feasible, can be used for massive production, and has a wide application prospect.

The invention discloses a method for preparing bismuth selenide nano particles, which comprises preparation of starch solution, preparation of bismuth nitrate solution, preparation of sodium selenide sulfite solution, preparation of bismuth selenide colloidal solution and preparation of the bismuth selenide nano particles so as to obtain a novel semiconductor quantum dot material of the bismuth selenide nano particles, wherein the used raw material is nontoxic bismuth nitrate, the used surfactant or stabilizing agent is nontoxic pollution-free soluble starch, the used solvent is nontoxic pollution-free purified water, the used precipitating agent is nontoxic pollution-free acetone, and the used washing agent is nontoxic pollution-free acetone or anhydrous ethyl alcohol, so the method has little harm to human body and pollution to environment, has simple and reasonable process and lower cost for preparing the bismuth selenide nano particles, and develops a new way for the non-oxide semiconductor quantum dot material. Therefore, the method for preparing the bismuth selenide nano particles has the advantages of simple and reasonable process, lower cost, innocuity and little pollution.

The invention discloses a wide-band photodetector of A perovskite thin film based on A topological insulator bismuth selenide electrode and a preparation method thereof. A Bi2Se3 thin film electrode is arranged on a sapphire substrate, and a layer of FA0. 85Cs0. 15PbI3 perovskite thin film is arranged on that Bi2Se3 thin film electrode. The invention utilizes the characteristic of large specific surface area of perovskite thin film and the special conductive surface state of topological insulator, a The response of the photodetector is sensitive in the range of UV- visible-near infrared light.The detector of the invention has simple preparation process and good device performance, and opens up new prospects for the application of topological insulator material in photoelectric detectors.

The invention relates to a method for preparing a topological insulator Bi2Se3 (bismuth selenide) and perovskite oxide La0.7Sr0.3MnO3 composite structure. The method comprises the following steps of a, measuring, grinding and tabletting bismuth powder and selenium powder in an argon glove box according to a molar ratio of 2:3, sealing the bismuth powder and selenium powder into a vacuum quartz tube, and then sintering and quenching the bismuth powder and selenium powder to prepare Bi2Se3 single crystal wafers; b, dissolving lanthana, strontium carbonate and manganese acetate into a nitric acid solution according to a molar ratio of 7:3:10, adding a complexing agent, and placing the mixture into a furnace to be sintered to obtain La0.7Sr0.3MnO3 precursor powder; c, mixing the prepared precursor powder with a little silane coupling agent; d, adding silicone rubber into the precursor powder obtained in step c, uniformly mixing the silicone rubber and the precursor power, and tabletting the mixture; e, laminating the substrate obtained in step d with the Bi2Se3 single crystal wafers, pressurizing and solidifying the laminated substrate, and then stripping the Bi2Se3 single crystal wafers by utilizing an adhesive tape. The preparation process of the method is simple, the preparation period is short, easiness in operation can be realized, and the preparation cost is greatly reduced.

The invention discloses a method for preparing a bismuth selenide nanosheet on a mica substrate by controlling the gas flow. A catalyst assistance-free chemical vapor deposition method is adopted, anda tubular furnace with a one-port quartz tube is used as growth equipment; the flow of high-purity argon is 70 sccm, and the growth time is 30 min; the Bi2Se3 nanosheet grows on the mica substrate according to a gas-solid growth mechanism; the experimental method is simple and feasible, and has a wide application prospect.

The invention discloses a preparation method-vapor phase transmission method for a large-size ultrathin bismuth selenide (Bi2Se3) nanosheet. The preparation process includes the following steps: 1) according to a molar ratio of 2:3, weighing a certain amount of a bismuth powder and a selenium powder, cleaning a Si / SiO2 substrate and a quartz tube, and adhering the substrate on a quartz block with a high temperature resistant glue; 2) putting the raw materials of the bismuth powder and the selenium powder into one end of the quartz tube, vertically putting the other end of the quartz tube into the Si / SiO2 substrate, vacuumizing the quartz tube, and sealing; 3) putting the quartz tube into a high-vacuum tube furnace, according to a certain heating rate, carrying out heat preservation for a certain time at a set temperature, and then cooling along with the furnace; and 4) taking out and cutting apart the quartz tube, and thus obtaining the Si / SiO2 substrate grown with the Bi2Se3 nanosheet. The method adopts the high-purity bismuth powder and the high-purity selenium powder as the raw materials, and synthesis is carried out under the high temperature and high vacuum conditions, and thus the obtained Bi2Se3 nanosheet has good crystallinity and high purity, and has wide application prospects in the fields of optoelectronic devices, thermoelectric condensing units and the like.

The invention aims to provide a controllable and perpendicular bismuth selenide nanosheet thin film. The thin film comprises Bi2Se3 nanosheets perpendicular to a matrix, wherein the sizes of the nanosheets are 50 nanometers to 50 micrometers. The Bi2Se3 thin film is prepared by a chemical vapor deposition method. By the method, the high-quality thin film having obvious photoelectric response can be controllably prepared, it is found out that the thin film has N-type conductive characteristic by test, the thin film and a P-type silicon substrate can form an N-type thin film / P-type silicon waferdual-layer structure, and the thin film has obvious visible light and near-infrared light photoelectric response capability and relatively rapid photoelectric response time, particularly has high photoresponse capability at a near-infrared wave band and has favorable electric detection application prospect.

The invention discloses a bismuth selenide / carbon nanofiber composite anode material for a sodium ion battery and a preparation method thereof. The composite anode material is obtained by reacting a bismuth salt with small-molecule elemental selenium deposited in carbon nanofibers having a three-dimensional net structure and performing in-situ growth of bismuth selenide. The preparation method comprises the following steps of: firstly, preparing polypyrrole fibers by a template method; secondly, carrying out high-temperature activation on the polypyrrole fibers with the presence of a potassium hydroxide activator to obtain carbon nanofibers having the three-dimensional net structure; thirdly, uniformly mixing the carbon nanofibers with the elemental selenium and carrying out heat treatment; fourthly, dispersing the heat-treatment product in a bismuth salt solution through ultrasound treatment; finally, introducing the mixture into a high-pressure reaction kettle and carrying out hydrothermal reaction to obtain the bismuth selenide / carbon nanofiber composite anode material. The preparation method is simple, safe and reliable, is high in operability and low in cost, and is applicable for industrial production, and the composite material prepared according to the preparation method is endowed with favorable electrochemical performance when used for the sodium ion battery.

The invention provides a topological insulator material and a preparation method thereof, and belongs to the field of preparation of novel materials. The topological insulator material is an antimonytelluride / tellurium segmented nanowire array or a tellurium nano disc array. The regular antimonytelluride / tellurium segmented nanowire array or the tellurium nano disc array is directly obtained on the template by a template assisted method; and the prepared nano material is used for regulating and controlling the topological insulation performance of the material. Compared with the traditional method for preparing bismuth selenide materials, the preparation method of the topological insulator material has the characteristics of simplicity, low cost, one-step molding and the like.

The invention discloses a method for growing a bismuth selenide high-index surface single crystal thin film on a silicon (211) substrate. The method comprises the following steps: 1), performing flashing silicon treatment or chemical etching treatment on a Si substrate having a crystal plane orientation of (211); 2), raising the temperature of a Bi beam source, depositing and growing a Bi buffer layer on the Si (211) substrate prepared in the step 1); 3), after the Bi buffer layer is grown in the step 2), adjusting the temperature of the Bi beam source, raising the temperature of a Se crackingbeam source, and starting to grow a Bi2Se3 nucleation layer; 4): after the growth of the Bi2Se3 nucleation layer is completed in the step 3, continuing to grow a Bi2Se3 high-index surface single crystal epitaxial thin film to obtain the bismuth selenide high-index surface single crystal thin film. According to the method, the Bi ultra-thin single crystal layer is adopted as a buffer layer, the low-temperature Bi2Se3 nucleation layer with a thickness of 3-5 nm is grown on the surface of the Bi buffer layer, then the growth temperature is appropriately increased to grow the Bi2Se3 high-index surface single crystal thin film epitaxial layer, and the Bi2Se3 high-index surface single crystal thin film having a relatively good crystallinity can be obtained.

The invention relates to a unit structure of a tunable graphene artificial surface polarization insensitive topological insulator electromagnetically-induced transparent material. The structure comprises a dielectric layer and a topological insulator body; and the front side of the dielectric layer is coated with the topological insulator body. The topological insulator body is of a square shape,the dielectric layer is of a rectangle shape, and a material of the topological insulator body is bismuth selenide. The unit structure has a polarization insensitive electromagnetically-induced transparent phenomenon, and is simple in structure, simple in machining process, small in size and applicable to preparation of a micro device.

The invention relates to a method for synthesizing selenium and a bismuth selenide nano material by using lysinibacillus sp.ZYM-1. The method comprises the following steps: adding 0.5-25mM of sodium selenite into an LB culture medium subjected to high-temperature sterilization at 121 DEG C, inoculating ZYM-1, and culturing for 24-48h under the condition that the temperature is 25-40 DEG C, the pH value is 5-9 and the speed is 50-300rpm to obtain a red electroselenium nano material; and adding 0.5-25mM of sodium selenite and 0.1-5mM of bismuth nitrate solution into the LB culture medium subjected to high-temperature sterilization at 121 DEG C, inoculating ZYM-1, and culturing for 24-48h under the condition that the temperature is 25-40 DEG C, the pH value is 5-9 and the speed is 50-300rpm to obtain a black bismuth selenide nano material. The reaction is carried out in aqueous solution without severe conditions of high temperature, high pressure and the like, so that cultivation can be enlarged easily. The prepared selenium nano spheres can be applied to adsorption removal of heavy metals, and biosynthesis of the prepared bismuth selenide nano material is not reported at present.

The invention discloses a preparation method of a high-quality bismuth selenide single crystal. According to the preparation method of the high-quality bismuth selenide single crystal, the molar ratioof Bi to Se is appropriately adjusted, a small excessive amount of Se is introduced as a transport agent, the problems that Se has high volatility and it is not easy to prepare a bismuth selenide compound with an ideal ratio are solved at the same time without introducing additional transport agents and fluxing agents, and the p-type or n-type high-quality bismuth selenide single crystal is prepared through an auto-doping effect. A bismuth selenide single crystal sample synthesized by the preparation method has high purity, an ideal stoichiometric ratio, a simple, environment-friendly and advanced synthesis process and high repeatability; and the synthesis product has a significant scientific value for studying the topological non-triviality of topological insulator materials.

The invention discloses a preparation method of enzyme-supporting bismuth selenide nanoparticles to release oxygen upon exposure to light, and relates to the field of synthesis in pharmaceutical chemistry, in particular to a method, including the steps, such as synthesizing hollow mesoporous bismuth selenide, synthesizing enzyme-supporting bismuth selenide, and loading perfluorocarbon. The preparation method of the enzyme-supporting bismuth selenide nanoparticles to release oxygen upon exposure to light comprises the specific steps of (1) synthesizing bismuth selenide through a hydrothermal process; (2) synthesizing glucose oxidase adsorbed to hollow mesoporous bismuth selenide shells by means of an ion adsorbing process; (3) filling bismuth selenide cavities with perfluorocarbon through an ultrasonic process, and filling with oxygen. A composite nano-drug delivery system acquired herein has the advantages of precision control of oxygen release, good photothermal properties, good biocompatibility and the like.

The invention belongs to the related technical field of photoelectric detection and discloses an oxygen plasma treated bismuth oxyselenide nanosheet photoelectric detector and a preparation method. The preparation method comprises the following steps of (1) preparing a bismuth oxyselenide nanosheet on a substrate by using a chemical vapor deposition method; (2) preparing a pair of source-drain metal electrodes on the bismuth oxyselenide nanosheet by adopting a laser direct writing or electron beam exposure technology in combination with thermal evaporation and electron beam evaporation; and (3) carrying out oxygen plasma treatment of the bismuth oxyselenide nanosheet to obtain a bismuth oxyselenide nanosheet photoelectric detector. The preparation method is advantaged in that a plasma processing method is adopted, the preparation method is simple in process, easy to operate and relatively low in cost, is expected to be applied to large-scale improvement of performance of a bismuth oxyselenide nanosheet photoelectric detector, and lays a foundation for application of bismuth oxyselenide in the photoelectric detector.

The invention relates to a hydrothermal preparation method of bismuth selenide nano powder. The hydrothermal preparation method specifically comprises the steps: S1, mixing and stirring raw materialsto obtain a reaction solution; and adding a surfactant according to the need of regulating and controlling the morphology of a powder crystal; S2, transferring the reaction solution obtained in the step S1 into a hydrothermal reaction kettle, carrying out a reaction at the temperature of 150 DEG C-250 DEG C for 12-36 h, and cooling to room temperature; and S3, carrying out centrifugal separation on the solution after the hydrothermal reaction to obtain solid powder, washing the solid powder with pure water and absolute ethyl alcohol for multiple times, and carrying out vacuum drying to obtainflaky or rod-like bismuth selenide nano-powder. The method is simple and easy to operate, toxic organic solvents and reducing agents are not used, the aqueous solutions and non-toxic raw materials areused, and the obtained product is pure in phase, high in crystallinity, controllable in size and morphology, high in product yield and environmentally friendly in preparation route.

The invention discloses a processing technology for producing a composite board by utilizing waste PET bottle flakes. The composite board produced by utilizing the waste PET bottle flakes comprises afirst plastic board layer, a second plastic board layer and a steel wire mesh cushion layer located between the first plastic board layer and the second plastic board layer; the steel wire mesh cushion layer is additionally arranged between the first plastic board layer and the second plastic board layer, so that the two sides of the steel wire mesh cushion layer are embedded into the first plastic board layer and the second plastic board layer correspondingly, then the composite board formed by the first plastic board layer and the second plastic board layer is more compact in bonding, the bearing capacity of the composite board is improved, and the service life of the plastic composite board is greatly prolonged; and glass fiber, bismuth selenide layered nano materials, zirconium selenide layered nano materials, niobium disulfide layered nano materials, silicon nanowires and silver nanowires are added into the preparation process of the first plastic board layer and second plastic board layer, so that the mechanical strength of the plastic composite board is effectively improved.

The invention relates to a chemical etching method for a bismuth selenide material. The chemical etching method includes the following steps that 1, a mask is manufactured, wherein the mask is a photolithographic mask and is manufactured through standard lithography and attached to the bismuth selenide material on a silicon substrate; 2, an etching agent is prepared, wherein the etching agent is a compound potassium bichromate acid solution and is prepared by evenly mixing, by volume percent, 9% of a potassium dichromate saturated aqueous solution, 48% of concentrated hydrochloric acid and 98% of concentrated sulfuric acid in a certain proportion; 3, etching is conducted, wherein compound potassium bichromate acid solution etching liquid obtained in step 2 is utilized to conduct etching on the bismuth selenide material of the attachement photolithographic mask obtained in attachment step 1. The chemical etching method is simple in process, convenient and fast to operate, low in cost and remarkable in effect and has the advantages that the etched bismuth selenide material is smooth in surface and meets the stoichiometric ratio, and the etching rate is convenient to control.

The invention discloses a preparation method of a self-supporting two-dimensional selenium oxide crystal array, and belongs to the technical field of semiconductor materials. The method comprises the following steps: placing bismuth selenide powder as a selenylation material in an upstream low-temperature area of a tubular furnace, gasifying the bismuth selenide powder by low-temperature evaporation, carrying the bismuth selenide to a central high-temperature area through carrier gas argon to carry out gas-phase chemical reaction with bismuth oxide, and depositing the bismuth selenide to a sodium chloride single crystal substrate in a downstream low-temperature area; and the two-dimensional bismuth selenide crystal array with consistent epitaxial orientation is formed. And then, spin-coating an organic polymer on the surface of the material, heating, and dissolving a sodium chloride single crystal substrate in deionized water after the organic polymer is cured, so as to obtain an organic polymer film adhered with the self-supporting two-dimensional selenium bismuth oxide array, and transferring the organic polymer film onto other substrates. According to the method, the preparation problem and the subsequent transfer problem of the two-dimensional selenium oxide nanosheet array are solved, the emerging material is expected to be applied to flexible devices and developed to wearable equipment, and the method has wide application prospects.

The present invention discloses a dual-mode imaging photothermoluminescence probe and a preparation method thereof and an application thereof. The dual-mode imaging photothermoluminescence probe comprises a core body and a coating layer coated on the core body, the core body is a photothermal material, the photothermal material comprises a bismuth selenide nano material, a material of the coatinglayer comprises polydopamine, and a near-infrared dye is bonded to an outer surface of the coating layer facing away from the core body. The dual-mode imaging photothermoluminescence probe has a strong photothermal effect, is stable in structures and chemical properties, has near-infrared two-region imaging and CT imaging functions, and can effectively inhibit tumor cell growth. Moreover, the preparation method can effectively ensure stability of the structures and performances of the prepared dual-mode imaging photothermoluminescence probe, conditions are easy to control, and the preparationmethod effectively improves production efficiency and reduces economic costs.