10454results about "Material nanotechnology" patented technology

The invention discloses an intelligent defect detection system and a self-repairing method for a flexible base material RFID tag, and belongs to the technical field of Internet of Things electronic device manufacturing. According to the system, a three-dimensional dynamic scanning system is constructed by integrating a high-resolution image acquisition module, a multispectral sensor array and a mechanical arm motion platform, and surface and internal structure characteristics of a flexible substrate are captured in real time. A defect identification algorithm based on deep learning is combined with a multi-scale convolutional neural network and a transfer learning technology, precise classification of 12 types of defects such as microcracks, conductive layer fractures and base material deformation is realized, and the detection precision reaches 99.2%. A dual-mode self-repairing mechanism is put forward, specifically, nano-silver conductive colloid is injected through a microfluid channel for the defects of the conductive layer, and 3D structure reconstruction is achieved through a controllable temperature field; for substrate damage, a photoresponse shape memory polymer patch is adopted, and molecular-level bonding repair is achieved after ultraviolet light activation. According to the scheme, the detection efficiency is improved by more than 5 times, and the radio frequency performance of the tag is recovered to 98.7% of the initial value after self-repairing.

The invention discloses a positive electrode material for a zinc-bromine flow battery and a preparation method and application thereof, and belongs to the technical field of zinc-bromine flow batteries, the preparation method comprises the following steps: crushing and sieving an active carbon source, adding the active carbon source into a graphene oxide aqueous dispersion, stirring, centrifuging, removing supernate, drying, mixing with an activating agent, and activating in an inert atmosphere; washing to be neutral, drying and sieving to obtain a graphene / activated carbon composite material; and attaching the graphene / activated carbon composite material to a carbon-plastic bipolar plate to obtain the positive electrode material for the zinc-bromine flow battery. A graphene / activated carbon composite system is combined with a high-conductivity network, graded holes and surface functional groups, so that the reaction kinetics bottleneck of a traditional carbon material Br2 is broken through.

The invention provides anti-ionizing radiation powder with a core-shell heterogeneous gradient structure and a preparation method and application of the anti-ionizing radiation powder, and belongs to the field of radiation protection.The preparation method of the anti-ionizing radiation powder with the core-shell heterogeneous gradient structure comprises the following steps that high-atomic-number metal salt is added into deionized water, aging, washing, drying and primary calcination are conducted in sequence, and the anti-ionizing radiation powder with the core-shell heterogeneous gradient structure is obtained; a core layer is obtained; the core layer and low-atomic-number metal salt are added into deionized water, aging, washing, drying and primary calcination are sequentially conducted, and preliminary wrapping powder with the high-atomic-number metal core layer wrapped by low-atomic-number metal is obtained; and adding the preliminarily wrapped powder and rare earth salt into deionized water, and sequentially performing aging, washing, drying, primary calcining, secondary calcining, airflow crushing and air rotation purging to obtain the anti-ionizing radiation powder with the core-shell heterogeneous gradient structure. Through cooperation of the core-shell heterostructure, the high-atomic-number oxide, the low-atomic-number oxide and the multi-element rare earth element, the shielding performance of the material is remarkably improved.

The invention relates to an iridium dioxide catalyst and a preparation method and application thereof, the iridium dioxide catalyst is a material with a three-dimensional porous structure, and the three-dimensional porous structure comprises mesopores and macropores; the characteristic peak of rutile type iridium dioxide exists in the XRD spectrogram of the iridium dioxide catalyst. When the catalyst disclosed by the invention is used as an anode catalyst in water electrolysis hydrogen production, the loading capacity of the catalyst can be effectively reduced, the dispersity is improved, and meanwhile, the catalyst has better mass transfer effect and conductivity, higher catalytic activity and excellent stability.

The invention discloses a method for preparing nano barium titanate based on sol-gel synergistic hydrothermal reaction, which comprises the following steps: (1) dissolving barium acetate in an acetic acid aqueous solution to obtain a barium source solution; weighing tetrabutyl titanate according to the molar ratio of barium to titanium being greater than 1.25, and dissolving the tetrabutyl titanate in alcohol to obtain a titanium source solution; (2) uniformly mixing the barium source solution and the titanium source solution, preserving heat at 20-80 DEG C to obtain gel, drying and grinding to obtain white powder of the barium titanate precursor: (3) preparing a 2-4mol / L inorganic strong alkali aqueous solution, adding the white powder and a dispersing agent into the inorganic strong alkali aqueous solution, and fully stirring to obtain a barium titanate precursor suspension; and (4) transferring the barium titanate precursor suspension into a reaction kettle for hydrothermal reaction, and after the reaction is completed, washing, drying and grinding to obtain the nano barium titanate powder. The preparation method is low in cost, and the prepared nano barium titanate powder is uniform in distribution, spherical or sphere-like in morphology, small in particle size, 80-150nm in average particle size and good in particle crystallinity.

The invention discloses a self-energy-supply multi-mode sensing electronic skin based on ionic gel heterojunction array integration and a preparation method and application of the self-energy-supply multi-mode sensing electronic skin. The electronic skin adopts a multi-layer composite structure design and comprises an electrode array layer, a silver paste connecting layer, a nano material doped ionic gel array layer and a pure ionic gel continuous layer, and passive self-energized work is realized through a space ion migration effect at a heterogeneous gel interface. The method is characterized in that the design of a multi-layer flexible composite structure is adopted, space-time coded light, temperature, pressure and humidity four-mode stimulation can be synchronously converted into electroneurographic signals, and a collaborative identification strategy of response intensity dynamic range and synaptic learning / delay time difference is utilized; and high-precision decoupling of the multi-source signals is realized in combination with a classification decision tree algorithm. The electronic skin has the characteristics of flexibility, deformation, environment self-repairing and bionic synapse, and geometrical characteristics of a reconfigurable target source are fused through time-space domain multi-modal data.

The invention belongs to the technical field of preparation of sensor materials, and particularly relates to a room-temperature formaldehyde sensor material based on a catalytic principle as well as preparation and application of the room-temperature formaldehyde sensor material. The polyphenol is adsorbed on the surface of the semiconductor metal oxide through chelation, then noble metal ions are introduced, and the polyphenol on the surface of the semiconductor metal oxide can capture the noble metal ions and reduce and stabilize the noble metal ions on the surface of the semiconductor metal oxide; the noble metal nanoparticles are anchored on the surfaces of the semiconductor metal oxide nanoparticles, the original morphology of the semiconductor metal oxide is maintained, and the noble metal nanoparticles are loaded on the surfaces of the semiconductor metal oxide nanoparticles. The nano composite material not only has the intrinsic electrical and thermodynamic properties of semiconductor metal oxide, but also combines the catalytic characteristics of noble metal nanoparticles, so that the lower detection limit of formaldehyde is reduced to 3ppb, and the sensitivity of the sensor is remarkably improved. The preparation method of the room-temperature formaldehyde sensing material is simple and suitable for large-scale production, the raw materials are simple and easy to obtain, the cost is low, and the materials are environment-friendly.

The invention relates to a carbon quantum dot for strengthening and promoting growth of microalgae and application thereof. In the process of preparing the carbon quantum dots by a conventional hydrothermal method, a precursor mixture is subjected to acidification modification in advance, the pH value is adjusted to 2 by using nitric acid, and then a hydrothermal reaction is performed, so that the prepared carbon quantum dots have the capability of promoting the growth of microalgae. However, if other acids are adopted or pH adjustment is not in place, the effect cannot be achieved, and even the inhibition effect can be achieved. The obtained product is good in effect and stable in performance, no special reaction device needs to be additionally arranged in the acidification modification process, and the method has the advantages that operation is easy and convenient, raw materials are easy to obtain, and the process can be quantified; the method is simple and convenient in process operation, has universality and is easy for industrial production.

The invention belongs to the technical field of micro-nano processing, and particularly relates to a preparation method and application of a metal micro-nano tube array. Comprising the following steps: preparing a metal layer on the surface of a substrate; coining glue is sprayed on the surface of the metal layer, then coining is conducted through a template, and a micro glue column array is formed after curing; a plasma etching process is adopted, the micro glue column array is used as a mask, the metal layer exposed out of the gaps in the bottom of the micro glue column array is etched, and a structure with the micro glue columns wrapped by metal is formed; and removing the rubber columns in the structure of the metal-coated micro rubber columns to obtain the metal micro-nano tube array. According to the invention, a residual-layer-free imprinting technology is adopted, the problem of glue layer residue in traditional imprinting is avoided, and the etching uniformity is improved. A plasma dynamic balance process is adopted, the side wall redeposition effect of etching by-products is utilized, and the metal micro-nano tubes are formed in a self-assembly mode. The prepared metal micro-nano tube array has high aspect ratio compatibility, and the nano tube array with the aspect ratio as high as 10: 1 can be realized.

The invention relates to the technical field of proton exchange membrane fuel cell cathode catalysts, and discloses a nanoscale high-entropy intermetallic compound catalyst and a preparation method and application thereof. According to the nanoscale high-entropy intermetallic compound catalyst, a nitrogen-doped porous carbon material derived from zeolite imidazole skeleton-8 is taken as a carrier, and the metal elements of a high-entropy intermetallic compound comprise platinum, copper, cobalt, nickel and iron or platinum, ruthenium, copper, cobalt, nickel and iron. The preparation method of the catalyst comprises the following steps: step 1, preparing a zeolite imidazole framework 8; 2, preparing and purifying a nitrogen-doped porous carbon material carrier; step 3, loading a metal precursor; and 4, preparing the nano-scale high-entropy intermetallic compound catalyst. Nanoscale, high dispersity and structure ordering of the high-entropy intermetallic compound are achieved, the high-entropy intermetallic compound serves as a PEMFC cathode catalyst, the ORR quality activity and durability can be remarkably improved, and Pt loading capacity and cost are effectively reduced.

The invention belongs to the technical field of rare and precious metal recovery, and particularly relates to a method for recovering metallic silver from waste crystalline silicon battery pieces, which comprises the following steps: (1) putting the waste crystalline silicon battery pieces into an inorganic alkali aqueous solution for soaking reaction to obtain an aluminum-containing solution and dealuminized crystalline silicon pieces; (2) adding the dealuminized crystal silicon wafer into a mixed solution of organic acid and hydrogen peroxide for soaking reaction, filtering and washing to respectively obtain silver-containing filtrate and a silver-removed silicon wafer; (3) carrying out chlorination precipitation reaction on the silver-containing filtrate and a chlorine source, filtering and drying to obtain silver chloride powder; (4) adding silver chloride powder into an ammonia water solution, heating and stirring to completely dissolve silver chloride to obtain a silver-ammonia solution; (5) adding PVP (Polyvinyl Pyrrolidone) into the silver-ammonia solution, heating and stirring until the PVP is completely dissolved, adding ascorbic acid, and carrying out reduction reaction at room temperature to obtain metal silver powder precipitate; and filtering, washing and drying the precipitate to obtain the spherical silver powder. According to the method, the silver recovery efficiency is high, the spherical nanoscale silver powder can be prepared, and the purity is high.

The invention discloses a dry-process high-temperature-resistant lithium battery diaphragm and a preparation method thereof, and relates to the technical field of lithium battery diaphragms. The specific preparation method comprises the following steps: activating and cross-linking polypropylene, polyimide, a PP-b-PI block copolymer and a cross-linking agent BIBP under the protection of nitrogen to prepare a polypropylene-polyimide matrix; after melting, adding a pre-sintered ZrO2-coated Al2O3 core-shell filler, hydroxylated boron nitride and zinc borate, and carrying out double-stage screw extrusion, ultrasonic orientation, nitrogen annealing and cold roller quenching to obtain a mixed melt; carrying out warm stretching and hot air circulation heat treatment to prepare a hard elastic crystal base film; carrying out stretching, thermal relaxation and thermal shaping to obtain a microporous base membrane; after slitting, plasma activation is carried out, epoxy silane and tetraethyl orthosilicate / polybenzimidazole aerogel precursors are sprayed, and a nano closed-pore coating is formed through pre-curing and heat shrinkage curing; and finally eliminating static electricity and rolling to obtain a finished product. The lithium battery diaphragm prepared by the invention is excellent in high temperature resistance and low in thermal shrinkage rate.

The invention provides a flow battery composite electrode, a preparation method thereof and a flow battery. The preparation method comprises the following steps: placing a pretreated carbonaceous substrate in a mixed solution of a surfactant, an electrolyte and a transition metal salt, growing a metal oxide nanosheet array on the surface of the pretreated carbonaceous substrate by using an electrochemical deposition process, washing, drying and roasting to obtain the flow battery composite electrode, wherein the feeding ratio of the surfactant to the transition metal salt is (1-2) g: (0.02-0.2) mol. The invention also provides the flow battery composite electrode prepared by the preparation method and a flow battery prepared from the electrode. According to the preparation method, the electrochemical reaction activity of the electrode in the all-vanadium redox flow battery can be optimized by regulating and controlling the chemical composition and the microstructure of the catalyst loaded on the surface of the carbon fiber.

The invention discloses silver powder with coexisting submicron sheets and nano-particles and a preparation method of the silver powder, and belongs to the technical field of silver powder preparation. A silver nitrate solution is added into a dispersing agent solution, then a directional end-capping reagent solution is added, and nucleation and growth of submicron sheets and nano-particles are controlled through the types of dispersing agents, the types of directional end-capping reagents, the temperature gradient and the like. The diameter of the prepared flaky silver powder ranges from 0.1 micrometer to 1.5 micrometers, the thickness of the flaky silver powder ranges from 30 nm to 120 nm, and the flaking rate ranges from 30% to 90%. And the particle size of the spherical silver powder is 30-150 nm. According to the preparation method of the silver powder, a silver nanocrystal seed solution does not need to be prepared independently, and the silver powder is different from common silver powder with single morphology, can be used for preparing the flake-shaped and particle-shaped coexisting silver powder in one pot, and is suitable for being used as a conductive functional phase of low-temperature curing type electronic paste.

The invention discloses a silicon-carbon negative electrode material, a preparation method thereof and a lithium ion battery, and relates to the technical field of lithium ion battery negative electrode materials. The material sequentially comprises a porous silicon core, a transition layer and a shell from inside to outside, the transition layer is a nitrogen-doped SiC / C composite layer, the shell comprises a graphene / carbon nanotube skeleton and MXene quantum dots, the MXene quantum dots are embedded in the graphene / carbon nanotube skeleton, boric acid ester bonds exist between carbon nanotubes and graphene, and the MXene quantum dots are embedded in the graphene / carbon nanotube skeleton. The silicon-carbon negative electrode material is based on dual-network dynamic bonding and stress gradient regulation and control, the cycle performance of the material can be remarkably improved, and the service life of the material can be remarkably prolonged.

The invention provides a phenolic resin-based spherical silicon-carbon composite material as well as a preparation method and application thereof, and belongs to the technical field of lithium battery materials. The preparation method comprises the following steps: preparing spherical phenolic resin by adopting a suspension polymerization method, curing to obtain phenolic resin microspheres, preparing porous carbon spheres by taking the phenolic resin microspheres as a carbon precursor in a carbonization and alkali activation manner, carrying out CVD vapor deposition on nano silicon, and carrying out carbon coating to obtain the phenolic resin-based spherical silicon-carbon composite material. The phenolic resin is utilized to form a highly cross-linked network structure after curing, the carbon spheres obtained after carbonization have good mechanical strength and rigidity, the porous structure of the porous carbon spheres provides a volume change buffering structure for nano-silicon, the lithium ion path is shortened, the spherical structure is beneficial to uniform dispersion, nano-silicon particles are prevented from gathering, and the performance of the lithium ion battery is improved. And the porous carbon spheres with high specific surface area can also improve the interface reaction activity, so that the problems of high volume expansion, low conductivity and slow ion diffusivity of silicon are solved.

The invention provides a method for improving the illumination stability of perovskite through post-treatment. The method comprises the following steps: S1, preparing a perovskite illuminant; s2, grinding and diffusing; and S3, inducing exposure and passivation of photoinduced defects. According to the invention, the light stability of the perovskite illuminant synthesized in a temperature solid state can be improved, so that the perovskite illuminant is applicable to wider application fields.

The invention provides an amphiphilic carbon dot, a carbon nanofluid and application of the amphiphilic carbon dot and the carbon nanofluid, and belongs to the technical field of nanomaterial oil displacement, and the amphiphilic carbon dot is prepared by taking alkylphenol polyoxyethylene ether and glucose as raw materials to perform solvothermal reaction; the alkylphenol polyoxyethylene ether comprises octylphenol polyoxyethylene ether and / or nonylphenol polyoxyethylene ether; the mass ratio of the alkylphenol polyoxyethylene ether to the glucose is 1: (0.1-2). According to the invention, alkylphenol polyoxyethylene ether and glucose are taken as raw materials, and simple preparation of the amphiphilic carbon dots with high surface and interface activity is realized. The amphiphilic carbon dots provided by the invention show good surface and interface activity at high temperature and high salinity. According to the carbon nanofluid provided by the invention, the amphiphilic carbon dots and the zwitterionic surfactant are compounded, so that the stability of a carbon nanofluid oil displacement system at high temperature and high salt can be further improved, the crude oil recovery rate is increased, and efficient yield-increasing development of high-temperature and high-salt deep oil reservoirs is realized.

The invention discloses a silicon-carbon material as well as a preparation method and application thereof. The silicon-carbon material comprises nitrogen-doped porous carbon and an amorphous carbon layer coating the nitrogen-doped porous carbon, and pores of the nitrogen-doped porous carbon are filled with boron-doped nano silicon. The nitrogen-doped porous carbon improves the affinity of silane gas while improving the electron conductivity, a high-conductivity and high-density silicon-carbon composite structure is realized, the boron-doped nano silicon and the nitrogen-doped porous carbon form a nano heterojunction site, and the migration rate of lithium ions is improved, so that electrochemical reaction kinetics is improved, and the electrochemical performance of the lithium ion battery is improved. The material has the advantages of high rate and long cycle performance.

The invention discloses a high-temperature-irradiation-resistant zirconium alloy and a manufacturing method and a workpiece thereof, and belongs to the field of zirconium alloys. Wherein the zirconium alloy resistant to high temperature irradiation comprises the following components in percentage by weight: not less than 96% of Zr, 0.61%-1.4% of Sn, 0.41%-1.4% of Nb, 0.1%-0.5% of Fe, 0.11%-0.2% of O and 0.001%-0.3% of Cr; and from 0.015% to 0.03% of Si and / or from 0.001% to 0.06% of Ge; wherein Sn + Nb + O is greater than or equal to 1.5%, Fe / Cr is greater than or equal to 1.5%, Si + Ge is greater than or equal to 0.015%, and (Sn + Nb + O) / (Fe + Cr + Si + Ge) = 1.5-25.0. The alloy has good mechanical properties, corrosion resistance, creep resistance and radiation growth resistance, and is suitable for manufacturing of pressurized water reactor core structural members.

The invention provides embedded metal fullerene and a preparation method thereof. The preparation method comprises the following steps: mixing a metal source and graphite powder, and filling a hollow graphite rod with the mixture to prepare an anode; the electrode is installed at the anode end of an electric arc furnace, and on-line activation is conducted through anode and cathode short-circuit current under the inert atmosphere; then carrying out arc discharge under specific air pressure and current, and collecting generated carbon ash; performing ultrasonic extraction by using an organic solvent to obtain a fullerene crude extracting solution; and finally, performing multi-stage separation and purification by high performance liquid chromatography, and performing primary and fine separation by sequentially adopting preparative and semi-preparative chromatographic columns to obtain a high-purity product. According to the method, a complete technical path capable of efficiently and controllably preparing the ultra-high-purity embedded metal fullerene is formed through a synthesis process integrating online activation and accurate atmosphere regulation and control and a multi-stage gradient chromatography purification strategy, and a solid foundation is laid for application of atomic-scale accurate materials in the frontier fields of quantum devices and the like.

This invention provides a transdermal nanoparticle delivery system for skin anti-inflammation, comprising a protein-blue calyx methyl ether-polymer shell capsule composite structure. The protein has an affinity for the skin, blue calyx methyl ether is loaded within the protein, and the polymer layer coats the surface of the protein. The blue calyx methyl ether nanoparticle transdermal delivery system has a size of 30-80 nm, and the polymer shell thickness is 10-35 nm. The surface properties of the polymer shell can be controlled according to the required transdermal delivery depth, enabling the protein to penetrate the skin barrier and be efficiently delivered deep into the skin, where the blue calyx methyl ether is then slowly released, targeting and alleviating skin inflammation. This addresses the drawback of low therapeutic efficacy of blue calyx methyl ether in treating skin inflammation due to unsatisfactory transdermal effects.

The invention relates to an electrolyzed water catalyst and a preparation method and application thereof, the electrolyzed water catalyst is a three-dimensional porous material of elemental iridium and / or iridium oxide, the specific surface area of the electrolyzed water catalyst is greater than or equal to 65 m < 2 > / g, the porosity is greater than or equal to 40%, and the electrolyzed water catalyst has a mesoporous and macroporous structure. The electrolyzed water catalyst disclosed by the invention has a large specific surface area, high porosity and a three-dimensional porous structure of mesopores and macropores, so that the electrolyzed water catalyst has better mass transfer performance and apparent catalytic activity. The three-dimensional porous structure of the catalyst can improve the utilization rate of the iridium element, so that the loading amount of iridium in a membrane electrode is reduced, and the catalyst has excellent stability. The preparation method provided by the invention is simple and convenient, and has relatively high economical efficiency.

The invention relates to a preparation method and application of a carbon dot-based nano enzyme. The preparation method of the carbon dot-based nano-enzyme comprises the following steps: taking sucralose and B vitamins as raw materials, and preparing the carbon dot-based nano-enzyme through a one-pot hydrothermal method. The preparation method of the carbon dot-based nano-enzyme provided by the invention is simpler in catalytic condition and higher in safety. The carbon dot-based nano-enzyme prepared by the invention has the advantages of high oxidase-like activity, low drug resistance, high biocompatibility and the like, can inhibit multi-drug-resistant bacteria, and can be applied to the aspects of aquatic product preservation and the like.

A copper-aluminum composite plate material prepared by aluminum liquid continuous casting and a process thereof. The method includes: S1, heating an aluminum ingot to 700-800° C. and smelting for 1-3 h; S2, degassing smelted aluminum liquid, and keeping the temperature and standing; S3, texturing a copper strip, and then cleaning; S4, heating the pretreated copper strip to 200-650° C.; S5, under the protection of inert gas, continuously casting the treated aluminum liquid on the treated copper strip, performing quenching crystallization on a copper-aluminum composite material, and performing oxygen-free continuous casting; and S6, continuous rolling: rolling the continuously cast copper-aluminum composite material to obtain the copper-aluminum composite plate material prepared by aluminum liquid continuous casting.

Microparticles for detecting biological materials are provided. Each of the microparticles includes: a core-shell structured microparticle consisting of a core including a magnetically responsive metal and a shell layer surrounding the core and having a uniform thickness; and capture probes introduced onto the shell layer to capture biological materials.

The invention relates to the technical field of lithium ion batteries, in particular to a diaphragm material for a lithium battery and a preparation method of the diaphragm material. Comprising a base film and a modified nano TiO2 coating, the modified nano TiO2 coating is arranged on at least one side surface of the base film, and the modified nano TiO2 coating comprises the following raw materials in parts by weight: 55-80 parts of a modified nano TiO2 composite material, 8-24 parts of a binder and 2.5-7.5 parts of a dispersant; the modified nano TiO2 composite material is prepared by taking cellulose nanocrystals, lanthanum zirconate and rare earth praseodymium as modifiers and nano TiO2 as a raw material, the mass ratio of the cellulose nanocrystal to the lanthanum zirconate to the rare earth praseodymium is (1-5): (2-3): 1. By adding the modified nano TiO2 composite material and introducing nano particles into the diaphragm, a three-dimensional network structure is formed, the liquid absorption property and the ionic conductivity of the diaphragm are improved, and meanwhile, the diaphragm is high in air permeability and relatively good in mechanical property and ionic conductivity.

The embodiment of the invention provides a silicon-carbon negative electrode material and a preparation method thereof, a negative electrode plate and a battery, the silicon-carbon negative electrode material comprises a silicon-carbon inner core and a coating layer coating the silicon-carbon inner core, and the silicon-carbon inner core comprises a porous carbon substrate and nanometer silicon arranged on the porous carbon substrate. The test result of the first cyclic volt-ampere test of the silicon carbon negative electrode material meets at least one of the following conditions: (a) the value of dQ / (dV * C) of a discharge differential capacity curve in a voltage interval of 0.45 V + / -0.05 V is less than or equal to 1.7, dQ / dV represents differential capacity, the unit is mAh / V, C represents charge capacity, and the unit is mAh; (b) no sharp peak exists in a discharge differential capacity curve in a voltage interval of 0.45 V + / -0.05 V, the battery can present a smooth and stable discharge process, the capacity retention ratio and the stability of the battery after circulation are improved, and the preparation method is simple, convenient and feasible, and is suitable for industrial production.

The invention discloses a silicon / graphite / carbon-aluminum oxide composite negative electrode material and a green preparation method thereof, and belongs to the technical field of lithium ion batteries. Aiming at the problems of high volume expansion rate and poor cycling stability of a silicon-based negative electrode and high cost of a traditional process, the invention innovatively provides the following scheme: 1) waste photovoltaic silicon wafer ball-milling liquid and waste graphite are taken as core raw materials, and resource recycling is realized; (2) phenolic resin and chitosan are adopted as double carbon sources, a nitrogen-doped carbon layer (the nitrogen content is 3-5 wt.%) is formed through pH-induced self-assembly, and the conductivity and the Li < + > diffusion rate are synchronously improved; and 3) aluminum nitrate is introduced for pyrolysis to generate 2-5nm aluminum oxide for doping, so that the side reaction of the electrolyte is inhibited, and the volume expansion of silicon is relieved (the expansion rate is less than or equal to 120%). The preparation process comprises the steps of silicon / graphite dispersion, double-carbon-source compounding, ammonia water regulation and control precipitation and gradient calcination. Experiments show that the specific capacity of the optimized material under the current of 0.5 A / g reaches more than 800mAh / g, the 100-time cycle capacity retention ratio is more than 98%, the 1000-time cycle capacity retention ratio is more than 80%, the reversible specific capacity under the multiplying power of 3A / g is more than 550mAh / g, and the raw material cost is reduced by 40%. The invention has the advantages of high capacity, long service life, environmental protection and economy, and provides an innovative solution for the fields of power batteries and energy storage.

The invention discloses a preparation method and application of washable tin-based perovskite quantum dots, and the preparation method comprises the following steps: mixing cesium iodide powder, tin iodide powder and mesoporous silica powder, and then placing the mixture in a plasma ball mill for ball-milling diffusion, cesium iodide and tin iodide react in a confinement space of mesoporous silica to generate a CsSn I < 3 >-coated SiO2 composite structure, CsSn I < 3 > quantum dots are dispersed and coated in the mesoporous silica, and the application of the tin-based perovskite quantum dots in the anti-ultraviolet textile fabric is provided. The method has the following beneficial effects that the purpose of remarkably improving the stability of the tin-based perovskite quantum dots and the washing resistance of the textile is achieved.