743 results about "Hydrofluoric acid" patented technology

The invention belongs to the technical field of fuel cell electrode material preparation, and particularly relates to a carbon electrode material for a polypyrrole modified bio-based fuel cell and a preparation method of the carbon electrode material. Comprising the following steps: modifying rice hull low-temperature carbonized powder by sequentially adopting POSS (Polyhedral Oligomeric Silsesquioxane) containing unipolar functional groups and POSS containing polypolar functional groups to obtain modified low-temperature carbonized powder; and carrying out in-situ polymerization on a pyrrole monomer on the surface of the modified low-temperature carbonized powder, and carrying out high-temperature carbonization and hydrofluoric acid corrosion to obtain the polypyrrole modified bio-based fuel cell carbon electrode material. The polypolar functional group POSS not only is beneficial to the in-situ polymerization reaction of pyrrole, but also can form a continuous macromolecular chain, and a net structure is formed on the surface of the whole material. The effect of the unipolar functional group POSS is to improve the stability of the low-temperature carbonized powder in the high-temperature carbonization process, and more importantly, the unipolar functional group POSS is to provide a channel for subsequent hydrofluoric acid corrosion, etch away non-conductive substances and improve the conductivity and specific surface area of the carbon electrode material.

The invention discloses a gel solid electrolyte, a preparation method thereof and a lithium ion battery, and relates to the technical field of batteries. The gel solid electrolyte comprises the following components: a solvent, a lithium salt, an inorganic salt or an organic small molecule additive, an ester cross-linking agent polymeric monomer, a silazane polymeric monomer, a diluent and an initiator, the invention also provides a lithium ion battery comprising the gel solid electrolyte and a preparation method of the lithium ion battery. The preparation method has the beneficial effects that by introducing the silazane polymeric monomer and the ester cross-linking agent polymeric monomer, the silazane polymeric monomer and the ester cross-linking agent polymeric monomer can be subjected to a copolymerization reaction, so that in-situ curing of the electrolyte is realized. The silazane fragment in the high-molecular polymer skeleton can effectively realize the constraint on strong Lewis acid substances such as PF5 and can also remove hydrofluoric acid and trace water so as to realize the protection of positive and negative active materials.

The invention belongs to the technical field of laser processing, and provides a quartz crystal etching solution which comprises the following components in volume concentration: 10-30% of hydrofluoric acid, 1-5% of sulfuric acid, 0.1-0.3% of surfactant and the balance of water. By optimizing the proportion, the manufacturing precision and the production and manufacturing efficiency of the tuning fork wafer are improved. And the stable etching rate and the optimal etching surface are obtained, and meanwhile, the cost is saved for process replacement. The invention further provides a method for cutting the tuning fork of the quartz crystal through the laser. The method comprises the steps that S1, the cutting contour line of the tuning fork is preset on the quartz crystal; s2, performing laser cutting on the quartz crystal based on a preset cutting contour line, and forming a tuning fork contour on the quartz crystal; and S3, integrally soaking the quartz crystal in the quartz crystal etching solution, and separating out the tuning fork. The machining process of the quartz crystal tuning fork is simplified, the cutting quality is optimized, the method is suitable for the large-piece manufacturing process, and the cutting efficiency and the yield are greatly improved.

The invention discloses a method for recovering mixed acid waste liquid containing hydrofluoric acid, which comprises the following steps: reacting raw materials with sodium salt or potassium salt, and filtering to obtain filtrate; the raw material is mixed acid waste liquid containing hydrofluoric acid; feeding the filtrate into a diffusion dialysis device for treatment, wherein the diffusion dialysis device comprises a homogeneous anion exchange membrane; the recovery liquid obtained through treatment of the diffusion dialysis device is fed into a membrane separation device, the membrane material of the membrane separation device is an acid-resistant metal ion removal membrane, and the recovered mixed acid is obtained on the permeation side of the membrane separation device. According to the method, impurities and metal ions in the low-concentration waste acid solution can be effectively removed, the product reaches the electronic-grade recycling standard, the resource recycling rate is increased, the technological process is simple, energy consumption is low, and the method is suitable for industrial application and popularization.

The invention belongs to the technical field of battery electrolyte additives, and particularly discloses a sulfonamide / sulfonamide ester additive and application thereof in a sodium-ion battery electrolyte, the sulfonamide / sulfonamide ester additive is a compound with the structural formula shown in the formula (I): # imgabs0 #, the sulfonamide / sulfonamide ester additive provided by the invention can remove trace hydrofluoric acid and water existing in a battery by introducing amido; a group containing an F element is introduced, so that a compact passivation protection film can be formed on the surface of the electrode material, and further reaction of an electrolyte and the electrode material is isolated; a sulfonate group is introduced, the ionic conductivity of the electrolyte is improved, and a low-impedance electrode-electrolyte interface film can be formed, so that a sodium-ion battery electrolyte additive system with long service life and high safety is obtained; and the bottleneck problems of poor rate capability, short cycle life and the like of the sodium ion battery in the traditional carbonic ester and ether electrolyte are solved in a targeted manner.

The invention relates to a waste photovoltaic panel recycling method which comprises the following steps: crushing a waste photovoltaic panel until the size of the waste photovoltaic panel is 80-160 meshes, and preparing powder; carrying out acid leaching treatment on the powder, and respectively collecting a leaching solution and a solid material; an acid leaching solution adopted in the acid leaching treatment is a mixed acid aqueous solution of hydrochloric acid and sulfuric acid; the pH of the leachate is adjusted to be neutral with an alkaline agent, then the leachate is mixed with metal iron to be subjected to a replacement reaction, and metal copper is prepared; the solid material is mixed with water, hydrofluoric acid and a flotation agent are added into the obtained mixture for flotation treatment, floats and precipitates are collected respectively, the floats comprise silicon powder, the precipitates comprise glass powder, and the flotation agent comprises one or two of hexadecyl potassium hydrogen phosphate and sodium dodecyl sulfate. According to the recycling method, the silicon powder, the glass powder and the metal copper can be comprehensively recycled from the waste photovoltaic panel.

The invention provides a micro-nano optical fiber probe for biochemical component detection based on infrared spectroscopy and detection equipment, and a preparation method of the micro-nano optical fiber probe comprises the following steps: S1, selecting one section of a multimode quartz optical fiber as a sensing area, and then removing a cladding layer and a coating layer of the sensing area to expose a bare fiber; s2, dripping a mixed acid solution prepared from hydrofluoric acid and citric acid to the bare fiber to corrode the bare fiber, and then cleaning and blow-drying; immersing the treated multimode quartz optical fiber into a silane coupling agent solution, reacting for 0.5-1 hour, and then drying; s3, immersing the multimode quartz optical fiber treated in the step S2 into a solution containing silver nanoparticles, and reacting for 10-20 minutes to obtain an optical fiber modified by the silver nanoparticles; and S4, sputtering a gold layer on the surface of the silver-modified optical fiber by adopting a vacuum magnetron sputtering technology to obtain the micro-nano optical fiber probe with the silver-gold film layer. After the surface of the silver nanostructure is covered with the gold film, oxygen, water, corrosive molecules and the like are effectively prevented from making direct contact with silver. In addition, both the gold and the silver can support a surface plasmon resonance (SPR) effect, and particularly, the prepared detection equipment can ensure the sensitivity of the SPR.

The utility model discloses a bitter apricot kernel wastewater treatment device which comprises an equipment shell, a water inlet pipe and a water outlet pipe are respectively arranged on the equipment shell, and a wastewater treatment assembly communicated with the water inlet pipe and the water outlet pipe is arranged in the equipment shell; the wastewater treatment assembly comprises a plurality of groups of apricot shell adsorption tanks which are connected in series, apricot shells are filled in the apricot shell adsorption tanks and are used as adsorbents, the apricot shells adsorbing hydrocyanic acid are subjected to carbonization treatment, and the hydrocyanic acid is destroyed in the carbonization treatment process and forms a part of pyroligneous liquor; the hydrofluoric acid on-line detector is arranged at the downstream of the apricot shell adsorption tank and is used for detecting the content of hydrofluoric acid in the treated wastewater; the control valve group is connected to the water inlet pipelines and the water outlet pipelines of the apricot shell adsorption tanks and is used for controlling the working states of the multiple groups of apricot shell adsorption tanks. The device is efficient in use, easy to operate, low in maintenance cost, safe and reliable, hydrofluoric acid is eliminated in the carbonization process, waste water is recycled, and water resources are saved.

The invention provides a method for preparing beta-SiC containing a whisker structure from rice husks, and belongs to the field of comprehensive utilization of resources and inorganic non-metallic materials. The method comprises the following steps: carbonizing rice hulls in a protective atmosphere to obtain rice hull ash, removing impurities from the rice hull ash, and fully mixing the rice hull ash with NaCl and H3BO3 to obtain a rice hull ash mixture; and putting the two groups of rice hull ash mixtures into the same atmosphere furnace, introducing shielding gas, enabling the gas to sequentially pass through the H3BO3 mixture and the NaCl mixture in sequence, heating to 1300-1600 DEG C at a heating rate of 2-10 DEG C / min, performing high-temperature treatment for 1-5 hours, washing and drying the obtained solid, and firing in air to obtain beta-SiC. The silicon carbide product with high commercial value is prepared from the cheap rice hulls, hydrofluoric acid and other high-toxicity and high-corrosivity raw materials are not needed in the preparation process, the heat treatment temperature is low, large-scale production can be easily achieved, the problems that an existing industrial carbon thermal reduction method is large in process pollution and high in energy consumption can be solved, the production cost is reduced, and the method is suitable for industrial production. And industrial popularization and application are facilitated.

The invention discloses a drilling fluid plugging agent based on modified resin and fibers, and relates to the technical field of oilfield chemistry. The plugging agent comprises modified phenolic resin, modified epoxy resin, modified urea resin, modified polyester fiber and modified glass fiber. The modified phenolic resin is prepared by modifying phenolic resin with ethyl silicate, the modified epoxy resin is prepared by reacting a carbon nanotube grafted with a silane coupling agent with epoxy resin, and the modified urea-formaldehyde resin is prepared by reacting diisocyanate with urea-formaldehyde resin. The modified polyester fiber is prepared by reaction of a silane coupling agent and polyester fiber, and the modified glass fiber is prepared by reaction of boric acid ester and glass fiber etched by hydrofluoric acid. The plugging agent disclosed by the invention has excellent temperature resistance and pressure-bearing strength, and meanwhile, the influence on the rheological property of the drilling fluid is relatively small.

The invention relates to a quartz sand pickling process. The quartz sand pickling process comprises the following steps: S1, preparing a pickling solution; s2, under the condition of 100 + / -2 DEG C, quartz sand is soaked in acid liquor for 7-10 hours, and stirring is conducted at the speed of 1-2 r / min; and S3, cooling to below 50 DEG C after pickling, separating out quartz sand, washing for multiple times until the pH is neutral, and then drying to obtain a finished product. The mixed acid liquor of hydrofluoric acid and hydrochloric acid is adopted, and efficient impurity removal is achieved through the optimized acid liquor proportion. HF has strong complexing ability and can form soluble complexes with metal impurities in the quartz sand, and HCl dissolves metal oxides to generate soluble chlorides. And through combined regulation and control of high-temperature short-time stirring and low-speed stirring, the chemical reaction rate is further accelerated, and thoroughness and uniformity of impurity removal are ensured.

The invention discloses a two-dimensional layered MXene nanosheet and a preparation method thereof, and belongs to the technical field of MXene preparation. The method comprises the following steps: (1) etching an MAX phase powder material by using hydrofluoric acid to obtain an etched MAX phase; (2) centrifuging and drying the etched MAX phase to obtain multi-layer MXene powder; (3) carrying out homogenization treatment on the multiple layers of MXene powder; and (4) carrying out rapid annealing treatment on the powder obtained after homogenization treatment to remove functional groups on the surface of MXene so as to prepare the MXene nanosheet with a regular structure and few defects. The method effectively avoids the oxidation problem of MXene, realizes feasible preparation with uniform thickness, stability, regular shape and fewer defects, and has the advantage of replacing an organic reagent intercalation preparation method to become a mainstream preparation method.

The invention belongs to the field of semiconductor processing and manufacturing, and provides a temporary bonding and de-bonding method, a composite substrate preparation method and a wafer manufacturing method.The temporary bonding and de-bonding method comprises the steps that silicon oxide layers are formed on two silicon substrates; the silicon oxide layer is subjected to ion implantation, hydrofluoric acid treatment and plasma activation, temporary bonding of the two silicon substrates is realized through hydrophilic bonding, and a temporary bonding interface is cracked through de-bonding annealing, so that de-bonding is realized. According to the method, a bonding medium does not need to be used, the thermal properties of the two substrates can be kept consistent, and warping and breaking are effectively avoided; temporary bonding is high in strength and good in stability, the functional substrate can be greatly thinned through the method, and therefore the composite substrate is prepared or the method is further used for manufacturing a multi-layer wafer bonding structure.

The present invention belongs to the technical field of high-purity quartz processing and discloses a method for removing impurities from quartz inclusions by hydrothermal denudation combined with acid leaching. Gas-liquid inclusions on the surface of quartz sand are destroyed by hydrothermal reaction of quartz sand and calcium oxide, and xonotlite produced by the reaction is removed with dilute nitric acid and sodium carbonate solution; and then impurities dissolved in acid and excess acid solution are removed by acid leaching, cleaning and filtering to obtain pure quartz sand. The technology destroys the gas-liquid inclusions by the hydrothermal method and avoids the use of hydrofluoric acid in the acid leaching process, which can effectively reduce the environmental pollution caused by the acid leaching process, exhibiting excellent industrial application potential.

The invention discloses a lithium ion capacitor negative electrode based on an MXene carbon nanotube composite material and a preparation method thereof, and the main points of the technical scheme are that the lithium ion capacitor negative electrode based on the MXene carbon nanotube composite material is composed of an MXene sheet layer, a hydroxyl modified carbon nanotube and a binder; the MXene sheet layer is Ti3C2Tx, the interlayer spacing is 1.0-1.3 nm after the MXene sheet layer is etched by hydrofluoric acid, and the content of-OH functional groups on the surface accounts for 40-60% of the total functional groups; the diameter of the hydroxyl-modified carbon nanotube is 10 to 30 nm, the length of the hydroxyl-modified carbon nanotube is 500 to 2000 nm, and the hydroxyl modification degree of the hydroxyl-modified carbon nanotube is 2.5 to 4.0 mmol / g; the mass ratio of the MXene sheet layer to the hydroxyl modified carbon nanotube is 7: 3-8: 2, and the MXene sheet layer and the hydroxyl modified carbon nanotube are combined through hydrogen bonds to form a layered porous structure.

The invention relates to a preparation method of a biomass hard carbon negative electrode material and application of the biomass hard carbon negative electrode material in the field of energy storage. The method comprises the following steps: carrying out pretreatment, crushing and pre-carbonization treatment on a biomass raw material to obtain a pre-carbonized material; mixing and stirring the pre-carbonized material and an acid solution, washing and drying to obtain an acid-treated hard carbon material; soaking the obtained acid-treated hard carbon material in an alkaline solution, heating and stirring, washing and drying to obtain an alkali-treated hard carbon material; mixing the obtained alkali-treated hard carbon material with a pore-forming agent, carrying out ball milling, carrying out solid-liquid separation, and carrying out high-temperature carbonization and grinding on the obtained solid phase to obtain a powder sample; and mixing the obtained powder sample with hydrofluoric acid, and carrying out hydrothermal treatment to obtain the biomass hard carbon negative electrode material. The sodium ion battery prepared by taking the biomass hard carbon negative electrode material as a negative electrode material has the characteristics of high initial coulombic efficiency, high low-voltage platform specific capacity and excellent cycle performance and rate capability.

The present invention relates to a modified sodium iron phosphate pyrophosphate composite material and its preparation method and application, belonging to the technical field of sodium ion batteries. The preparation method of the present invention comprises the following steps: S1, adding a soluble doped metal salt solution and a surfactant to a ferrous phosphate solution, and dripping a hydrogen peroxide solution and a hydrofluoric acid solution within 40min-80min under the conditions of 60°C-80°C, reacting at 85°C-98°C for 2h-5h after the dropwise addition, and washing and calcining to obtain a flaky composite precursor; S2, dissolving the flaky composite precursor, a sodium source, a phosphorus source, and a carbon source in water, and obtaining a modified sodium iron phosphate pyrophosphate composite material through sand milling, spray drying, and heat treatment. Element doping and material modification are successfully achieved during the precursor synthesis, thereby achieving optimization of the crystal phase, reduction of the impurity phase, improvement of the energy density, conductivity, and other physical and chemical properties of the NFPP material, and reduction of its water absorption.

The present application provides a preparation method and application of an ordered mesoporous-microporous carbon composite material. The preparation method includes: (1) infiltrating a foaming material into a mixed solution containing phenolic resin, a silicon source, and a nonionic surfactant, and drying to obtain a first matrix; (2) mixing the first matrix with a phosphate compound and reacting to obtain a second matrix; (3) calcining the second matrix under an inert gas to obtain a third matrix; (4) reacting the third matrix with a hydrofluoric acid-containing solution to generate an ordered mesoporous-microporous carbon composite material. The ordered mesoporous-microporous carbon composite material prepared in the present application is corrosion-resistant, has a large specific surface area, a high porosity, good adsorption performance, and a low cost, and has excellent mechanical stability and chemical stability, and can adsorb, separate, and rapidly desorb organic pollutants in high-concentration wastewater.

The invention provides a composite flotation reagent for separating feldspar and quartz and a flotation method. The composite flotation reagent for separating the feldspar and the quartz comprises a first flotation agent, a second flotation agent and a third flotation agent, and the first flotation agent comprises, by mass, 20-25 parts of a collecting agent and 1-4 parts of a pH adjusting agent; and the second flotation agent comprises the following components in parts by mass: 6-8 parts of an inhibitor and 1-4 parts of mixed phosphate. According to the method, one-time flotation separation of quartz and feldspar is conducted on the lepidolite tailings through the flotation reagent, quartz fine sand with the SiO2 content higher than 99% can be obtained, the standard requirement of glass industry materials is met, and the effect is close to the flotation separation effect of hydrofluoric acid; therefore, the flotation process is simplified under the condition that the flotation effect is guaranteed, and compared with flotation separation conducted through a hydrofluoric acid method, the influence of flotation separation conducted through the composite flotation reagent for separating feldspar and quartz in the embodiment on the environment is greatly reduced.

The invention discloses a laser-chemical composite surface planarization process based on a laser stripping sheet. The method comprises the following steps: firstly, carrying out surface scanning on the surface of a wafer subjected to laser-ultrasonic stripping by adopting femtosecond laser, thinning the wafer to a first target thickness through an ultra-short pulse cold working mechanism, and optimizing the sharp corner fluctuation of the surface at the same time; then immersing the wafer into a hydrofluoric acid-nitric acid mixed solution containing a platinum / iridium catalyst, accurately etching the residual sharp corner by utilizing a selective catalytic reaction of a contact point of a catalyst plate and the wafer, and feeding back and adjusting processing parameters in real time through a morphology monitoring module and an infrared thermal imaging system; and finally, thinning to the required thickness by adopting chemical mechanical polishing, and obtaining an atomic-scale flat surface. According to the technology, through the synergistic effect of laser pre-thinning and chemical etching, the problems that a traditional grinding technology is low in efficiency and large in material consumption are solved, and the technology has the advantages of being efficient, low in damage, high in precision and the like and is suitable for surface treatment of hard semiconductor wafers such as silicon carbide and gallium nitride.

The invention provides a wet purification process suitable for silicon and precious metal of a waste photovoltaic laminated piece, which comprises the following steps of: immersing a waste crystalline silicon battery piece into a NaOH solution, and removing an aluminum wire on the surface of the crystalline silicon battery piece to obtain a dealuminized crystalline silicon piece; the dealuminated crystal silicon wafer is subjected to acid pickling, and a silver-removed crystal silicon wafer and silver leaching liquid are obtained; removing impurities from the silver-removed crystal silicon wafer through a hydrofluoric acid solution to obtain a high-purity crystal silicon wafer; and extracting the silver elementary substance from the silver leachate through a hydrazine hydrate reduction method. According to the wet purification process, the waste crystalline silicon battery piece can be subjected to high-purity recovery, and the high-purity crystalline silicon wafer and the silver elementary substance can be obtained.

The invention discloses porous carbon, a preparation method thereof and a silicon-carbon material with high silicon content. The preparation method comprises the following steps: dispersing a carbon raw material, modified nano silicon dioxide and carbon nanotubes in ethanol to obtain mixed slurry, and performing spray drying on the mixed slurry to obtain a carbon source precursor; the preparation method comprises the following steps: pre-carbonizing a carbon source precursor in an inert atmosphere, mixing pre-carbonized powder with an alkaline activator, and activating in an activating furnace to obtain activated powder; and adding the activated powder into a hydrofluoric acid solution for soaking, removing the modified nano silicon dioxide, filtering, washing and drying, thereby obtaining the product. The modified nano silicon dioxide is prepared by carrying out esterification reaction on fatty acid and nano silicon dioxide. The number of 2-50nm mesopores in the porous carbon structure is obviously increased, the interface bonding force of deposited silicon and the carbon-based carrier is improved, and the advantages of the silicon-carbon negative electrode material on the discharge gram capacity and the cycling stability are effectively enhanced.

The invention belongs to the technical field of back contact cells, and particularly relates to a back contact cell with a specific reduced repetition lamination layer and preparation and application thereof, and the back contact cell comprises a silicon wafer, a first semiconductor layer and a second semiconductor layer which are alternately arranged on the back surface of the silicon wafer, and a passivation layer and a reduced repetition lamination layer which are sequentially arranged on the front surface of the silicon wafer, the reduced repetition lamination layer comprises silicon nitride and carbon-doped silicon oxide which are sequentially arranged on the outer surface of the passivation layer, the corrosion rate of the carbon-doped silicon oxide in a hydrofluoric acid solution with the mass concentration of 5 wt% is 1.5 / s or below, the thickness of the carbon-doped silicon oxide is 60-150 nm, and the thickness ratio of the silicon nitride to the carbon-doped silicon oxide is 1: (0.5-2). According to the invention, the stability and the production yield of the film layer are improved while the optical effect is considered, the short-circuit current is improved, and the cell efficiency is improved.

The invention is suitable for the technical field of composite materials, and provides a laminated composite material toughening intermediate layer and a preparation method thereof, and the preparation method comprises the following steps: obtaining an aramid short fiber wet-laid non-woven felt by using a processing method of a wet non-woven material; then the aramid fiber surface is activated through hydrofluoric acid etching; the preparation method comprises the following steps: grafting soluble polyether-ether-ketone resin with an active end group on the surface of the aramid fiber, and impregnating the aramid fiber at the same time; and the polyetheretherketone resin grafted on the surface of the aramid fiber is re-endowed with crystallinity through acidification reduction reaction of the polyetheretherketone resin grafted on the surface of the aramid fiber. According to the invention, the interface bonding performance of the aramid fiber toughening middle layer in the laminated composite material is regulated and controlled, the interlayer toughness of the carbon fiber reinforced polyether-ether-ketone composite material laminated board can be effectively improved while the original crystallinity of the polyether-ether-ketone resin is maintained, the possibility of interlayer cracking can be obviously reduced, a brand new scheme is provided for interlayer toughening of such materials, and the application prospect is broad. The material has potential application prospects in the fields of aerospace special materials and the like.

The invention relates to the technical field of high-purity quartz purification methods, in particular to a high-purity quartz green low-consumption purification method which comprises the following steps: S1, plasma-assisted crushing pretreatment; s2, complex acid leaching-microwave synergistic impurity removal; s3, fluidized chloridizing roasting; s4, nano bubble water washing-targeted adsorption; s5, performing vacuum heat purification; according to the purification method of the high-purity quartz, the step of complex acid leaching-microwave synergistic impurity removal is adopted, highly toxic hydrofluoric acid in a traditional chemical acid leaching method is abandoned, and the toxicity of waste liquid is greatly reduced; compared with a traditional high-temperature chlorination method which needs a high temperature of 1300 DEG C or above, the method adopts fluidized chlorination roasting, so that the roasting temperature is reduced by 500 DEG C, and the energy consumption is reduced by 40%; nano-bubble ultrapure water is adopted for ultrasonic cleaning, the cleaning efficiency can be improved by 50%, and residual impurities are effectively removed; through innovative design and synergistic effect of all the steps, ultra-high purity of SiO2 with the purity being greater than or equal to 99.996% is realized, and meanwhile, environmental protection, energy conservation and consumption reduction as well as industrial stable production are taken into consideration.

The present invention belongs to the technical field of polymer composite material preparation and discloses a double-layer hollow structure photonic gel film with controllable water permeation and color change, as well as its preparation method and application. The method comprises the following steps: preparing a three-dimensional PS-SiO2 photonic crystal and a three-dimensional SiO2 photonic crystal; calcining the three-dimensional PS-SiO2 photonic crystal at high temperature, filling the crystal with a polymer, and curing the crystal with ultraviolet light to obtain a hollow SiO2 structural color gel; curing the three-dimensional SiO2 photonic crystal with a polymer, and then etching the crystal with hydrofluoric acid to obtain an inverse opal gel; and bonding the hollow SiO2 structural color gel and the inverse opal gel to form a double-layer hollow structure photonic gel film with controllable water permeation and color change. The photonic gel film can be used in snowmelt warning indicators at large ski resorts, portable alcohol solubility detectors, or anti-counterfeiting identification labels for small commercial packaging.

The invention belongs to the technical field of back contact cells, and particularly relates to a back contact cell and a preparation method thereof, and the method comprises the following steps: S2, sequentially forming a first semiconductor layer and a mask layer on the back surface of a silicon wafer, the mask layer being a phosphorus-doped silicon oxide layer; s3, forming a second semiconductor opening region on the back surface; s4, a mixed solution containing hydrofluoric acid and hydrogen peroxide is adopted to remove the front surface winding coating film layer, and then texturing and cleaning are carried out; s5, sequentially forming a passivation layer and an anti-reflection layer on the front surface; s6, the anti-reflection layer winding plating layer and the passivation layer winding plating layer are removed, and then oxidation cleaning is carried out; the oxidation cleaning process comprises first oxidation, first acid washing, alkali washing and second oxidation which are sequentially carried out, and a mixed solution containing ozone and hydrochloric acid is adopted in the second acid washing, the first oxidation and the second oxidation; and S7, depositing a second semiconductor layer on the back surface. According to the process flow, two steps are directly shortened, the cost is low, meanwhile, the filling factor of the battery is improved, and the conversion efficiency and the yield of the battery are further improved.

The invention discloses a glass etching device for laser induction and a fluoride-free etching method, and belongs to the technical field of glass etching.The etching device comprises an etching tank and an oil bath heating device, the etching speed can be increased by heating alkaline fluoride-free etching liquid, and the etching efficiency is improved. A composite stirring system of a magnetic stirrer and a stirring paddle can enable the fluoride-free etching liquid to circularly flow, so that the etching uniformity is improved, and the etching reaction is more favorably and stably carried out; the fluoride-free etching method adopts fluoride-free etching liquid, does not contain hydrofluoric acid, is safe and environment-friendly, and can avoid deterioration of through hole characteristics. Under the action of the fluorocarbon surfactant, the etching liquid has excellent wettability, and sodium hydroxide and potassium hydroxide in the etching liquid can perform high-selectivity etching on the glass after laser induction; the glass subjected to fluoride-free etching is high in surface smoothness and higher in through hole roundness, the surface and the inner wall of the through hole are smooth, the roughness of the inner wall of the through hole is smaller than 1 micron, the taper of the through hole is smaller, and a good etching effect is achieved.

The invention provides a preparation method of a fully-active lithium-silicon alloy negative electrode material, which comprises the following steps: (S1) adding lithium foil and silicon powder treated by hydrofluoric acid into a ball milling tank, and performing ball milling in an inert atmosphere to obtain mixed powder; (S2) pressing the mixed powder into a compact precast block; heating the precast block to 450-550 DEG C by using a smelting furnace, and keeping the temperature for 10-20 minutes, so that the lithium part is molten to wet the silicon; (S3) the temperature is increased to the reaction temperature of 680-850 DEG C, heat preservation reaction is carried out for 10-30 min, metal lithium and silicon are fully reacted, and molten alloy is obtained; and (S4) the molten alloy is sprayed to a water-cooled rotating copper roller through a quartz nozzle, the rotating speed of the rotating copper roller is 3000-5000 rpm, and the fully-active lithium-silicon alloy is obtained after cooling. The obtained lithium-silicon alloy has the characteristic of high amorphization, has extremely high ion-electron conductivity and relatively low hardness, and can relieve expansion and shrinkage of a negative electrode in a charging and discharging process, so that the rate capability and the cycling stability of a sulfide solid-state battery are improved.

The present invention provides a room-temperature quartz bonding method, comprising: S100, cleaning the surfaces of quartz wafers; S200, depositing silicon dioxide on two quartz wafers to form a silicon dioxide bonding film on the surfaces of the quartz wafers; S300, chemically mechanically polishing the silicon dioxide bonding film; S400, cleaning the quartz wafers with a hydrofluoric acid solution; and S500, bringing the silicon dioxide bonding films of the two quartz wafers into contact with each other and bonding the quartz wafers using a bonding machine. This method can achieve high-reliability bonding between quartz wafers at room temperature.