511results about "Tin oxides" patented technology

The invention discloses a SnO2 / SnS2 / AgS nano material with piezoelectric electro-catalytic tooth whitening and sterilizing performance and a preparation method and application thereof, and the preparation method comprises the following steps: (1) dripping a silver nitrate aqueous solution into a prepared SnO2 / SnS2 nano material aqueous dispersion, carrying out hydro-thermal treatment for 2 hours, centrifuging, washing and drying to obtain a SnO2 / SnS2 / Ag2S ternary semiconductor heterojunction nano material; (2) food indigo is adopted to simulate tooth surface pigments, piezoelectric electro-catalytic degradation is carried out by using the SnO2 / SnS2 / Ag2S ternary semiconductor heterojunction nanomaterial, and the pigment degradation efficiency can reach 95% or above; (3) the SnO2 / SnS2 / Ag2S heterojunction nanomaterial is used for piezoelectric electro-catalysis treatment of the streptococcus mutans pellicle, and the antibacterial rate of the pellicle can reach 90% or above; and (4) compared with a 3% H2O2 aqueous solution for treating the enamel surface structure, the SnO2 / SnS2 / Ag2S nano-material piezoelectric electro-catalysis treatment of teeth has small damage to the enamel surface structure. According to the invention, more nano materials with tooth whitening and sterilizing performance and the preparation method thereof are provided, so that the problems of single variety, single preparation method, low electron-hole separation efficiency and large side effect of the existing tooth whitening and sterilizing nano materials are solved.

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 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 discloses an oxygen-sulfur double-vacancy modified SnO2 / SnS2 / C nano material as well as a preparation method and application thereof, and belongs to the technical field of electrode materials. The preparation method comprises the following steps: mixing a structure regulating agent with tin salt, dropwise adding alkali liquor, stirring, and carrying out suction filtration to obtain Sn6O4 (OH) 4; the preparation method comprises the following steps: adding glucose and polyvinylpyrrolidone into distilled water, stirring to form a uniform solution, adding Sn6O4 (OH) 4 into the uniform solution, stirring, and carrying out ultrasonic and hydrothermal reaction to obtain SnO2 / glucose; and calcining the SnO2 / glucose and a sulfur source in an inert atmosphere to obtain the SnO2 / SnS2 / C nano material modified by oxygen and sulfur double vacancies. The SnO2 / SnS2 / C disclosed by the invention is used for a lithium / sodium ion battery negative electrode, can effectively relieve volume expansion of tin-based oxysulfide and improve the conductivity of an electrode material, and shows high charge-discharge specific capacity, excellent rate capability and high-rate long-cycle stability.

The invention discloses a gas-sensitive material for monitoring an environment-friendly gas characteristic substance CO as well as a preparation method and application thereof, and relates to the technical field of gas-sensitive materials. The preparation method comprises the following steps: dissolving tin tetrachloride pentahydrate, sodium hydroxide and polyvinylpyrrolidone, adding ammonium fluoride, reacting at 155-165 DEG C, drying the product, and calcining at 295-305 DEG C to obtain SnO2 nanoparticles; the preparation method comprises the following steps: performing ultrasonic mixing on SnO2 deionized water dispersion liquid and MoS2 nanosheet ethylene glycol dispersion liquid, and then drying to obtain the MoS2 / SnO2 composite material with a mesoporous hollow nanotube structure, and the volume ratio of ethylene glycol to deionized water is (0.9-1.1): 1. The MoS2 / SnO2 gas sensitive material has the advantages of low density, high pore volume, large specific surface area, high structural stability and the like. And when applied to a CO resistive sensor, the catalyst has good CO selectivity, high sensitivity and good long-term stability.

The invention relates to the technical field of lead-acid batteries, and discloses a negative electrode additive for a lead-acid battery and a preparation method of the negative electrode additive. The negative electrode additive is a composite material prepared by compounding SnO2, COF and a carbon nitride nanotube, the composite material is SnO2 coated COF coated porous carbon nitride nanotube, and the addition amount of the negative electrode additive is 0.25% of the mass of the negative electrode lead powder of the lead-acid battery; the SnO2 (at) COF (at) porous carbon nitride nanotube is added, so that the sulfation phenomenon of the negative electrode of the lead-acid battery is effectively improved, the high-rate partial charge state of the lead-acid battery is improved, the cycle life of the battery is further prolonged, the hydrogen evolution overpotential of the negative electrode plate is also improved, the precipitation of hydrogen is reduced, and the service life of the battery is prolonged. Furthermore, the water loss of the electrolyte, the increase of the internal pressure of the battery and the impact on the electrode plate can be effectively relieved, and the stability of the electrode plate and the battery is favorably maintained, so that the use performance of the battery is improved.

The invention discloses a carbon-material-doped titanium-based tin-antimony-nickel composite coating electrode and a preparation method and application thereof.The specific process includes the steps that a titanium sheet is pretreated, the treated titanium sheet is placed in electro-deposition liquid to be subjected to constant-temperature pulse electro-deposition, the titanium sheet is dried through a drying oven and then roasted in a muffle furnace, and a carbon-material-doped middle layer is obtained; and then the carbon material doped titanium-based tin-antimony-nickel composite coating electrode is obtained through cyclic thermal oxidation and quenching processes. According to the preparation scheme provided by the invention, the electrode surface is thick and rough, has a large number of defects and is excellent in electrocatalytic activity. Compared with a single coating, the composite coating has longer service life and higher ozone generation efficiency in the application of preparing ozone by electrolyzing water.

The invention relates to the technical field of synthesis and preparation of nano materials, in particular to a method for preparing tin dioxide powder, which comprises the following steps: S1, preparing a 0.1-5 mol / L tin salt solution, adding a compound additive into the tin salt solution, and carrying out ball milling treatment after ultrasonic dispersion to obtain a pretreated tin salt solution; s2, freezing and freezing the pretreated tin salt solution in an ultralow-temperature environment to obtain a frozen sample; s3, transferring the frozen sample into a vacuum freeze dryer for dehydration treatment to obtain solid powder; and S4, carrying out high-temperature calcination on the solid powder to obtain tin dioxide powder. Zero sewage discharge is achieved in the preparation process, the problem of sewage discharge and treatment of traditional liquid-phase powder preparation is solved, meanwhile, the phenomenon of sintering agglomeration accompanied by traditional solid-phase calcination can be avoided, high-quality superfine tin dioxide powder preparation is achieved, the method is simple and safe in process, and industrial large-scale production and preparation are easy to achieve.

The invention discloses a Ti / IrO2-SnO2-SbO2 gradient active coating anode with low cost and high stability and a preparation process of the Ti / IrO2-SnO2-SbO2 gradient active coating anode. The gradient active coating is characterized in that the gradient active coating is composed of 3-5 layers, the total thickness is 5-15 microns, the thickness of each layer is 1-5 microns, the molar percentage content of iridium in a bottom layer is 0-5%, the sum of the molar percentage content of tin and antimony is 95-100%, the molar percentage content of iridium in a surface layer is 10-20%, the sum of the molar percentage content of tin and antimony is 80-90%, and the thickness of each layer is 1-5 microns. The molar percentage content of iridium from the bottom layer to the surface layer is sequentially increased from 2% to 10%, the molar percentage content of tin and antimony is sequentially reduced from 2% to 10%, and the total iridium loading amount in the gradient active coating is 0.05-0.2 mg / cm < 2 >. The preparation method comprises the three steps of titanium substrate pretreatment, precursor salt alcohol solution preparation and gradient active coating preparation. By adopting a gradient coating mode, the thermal stress between the coating and the titanium substrate in the preparation process is remarkably reduced, the consumption of noble metal is reduced, the oxygen evolution activity of the anode is improved, and the service life of the anode is prolonged. The method is simple to operate and low in cost, and has remarkable industrialization advantages.

The invention discloses a SnO2 modified WO3 nanosheet composite gas-sensitive material as well as a preparation method and application thereof, and belongs to the technical field of inorganic composite materials. The preparation method comprises the following steps: dissolving WCl6 in ethanol, adding into a reaction kettle provided with a ceramic tube, carrying out hydrothermal reaction at 170-190 DEG C for 5-8 hours, taking out the ceramic tube, drying, and annealing to obtain a ceramic tube loaded with WO3 nanosheets; the preparation method comprises the following steps: dissolving SnO2, tin chloride and urea in water to obtain a mixed solution, adding the mixed solution into a reaction kettle filled with a ceramic tube loaded with a WO3 nanosheet, carrying out a hydrothermal reaction at 90-100 DEG C for 1-4 hours, taking out the ceramic tube after the reaction is finished, and drying to obtain the SnO2 modified WO3 nanosheet composite gas sensitive material, and enabling the SnO2 modified WO3 nanosheet to grow on the ceramic tube in situ. The preparation method is simple, the product is high in crystallinity and good in stability and is suitable for preparing a gas sensitive sensor material with high economical efficiency, and a sensor prepared from the SnO2 modified WO3 nanosheet composite gas sensitive material can effectively improve the gas sensitive performance of WO3 and shows an extremely high response value to nitrogen dioxide at a low temperature.

The invention relates to a preparation method of a pectin-derived carbon-coated amorphous tin-zinc composite oxide lithium ion battery negative electrode material. The method comprises the following steps: dropwise adding a tin tetrachloride solution and an acidified zinc oxide solution into a pectin solution to obtain a metal ion-pectin dispersion liquid; adding ammonia water to obtain a pectin precursor solution; freezing and solidifying with liquid nitrogen; and after freeze-drying, roasting for 3-5 hours to obtain the pectin derived carbon coated amorphous tin-zinc composite oxide lithium ion battery negative electrode material. The reversible specific capacity of the obtained composite material reaches 1339 mA h g <-1 > after 100 cycles under the current density of 0.2 A g <-1 >.

The invention discloses a stannic oxide-based ammonia gas sensor as well as a preparation method and application thereof, relates to the technical field of gas sensors, and solves the problems of high detection lower limit, poor gas selectivity and low sensitivity of a traditional semiconductor ammonia gas sensor. A sensitive material based on oxygen vacancy regulation and control SnO2 / ZIF-67 is prepared on the surface of an interdigital gold electrode by adopting a chemical vapor deposition method, a planar electrode, an aluminum oxide ceramic substrate, a heater and a Pt wire are welded and packaged according to a general indirectly-heated gas sensitive element, and the SnO2 / ZIF-67 semiconductor ammonia gas sensor is prepared. The lower detection limit of the SnO2 / ZIF-67 semiconductor ammonia gas sensor is 1 ppm; meanwhile, the NH3 selectivity and sensitivity of the sensor are improved through the synergistic effect of SnO2 and ZIF-67, and the sensor can be used for detecting ammonia gas leakage and can be applied to judging the safety of ammonia gas in chemical production operation, environmental gas detection and other applications.

The invention relates to an oxygen-deficient nano material and a solid-phase melting zinc thermal reduction preparation method and application thereof, zinc powder is taken as a reducing agent, target metal oxide such as anatase type TiO2 and zinc powder are uniformly mixed, then mild high-temperature annealing treatment is carried out in an inert gas atmosphere, a product is washed by dilute acid / alkali, and the oxygen-deficient TiO2-x nano material is obtained. Similarly, oxygen deficient SnO2-x, ZrO2-x, and BaTiO3-x materials can be produced by such methods. Compared with the existing technologies of high-temperature hydrogen reduction, complex structure carbonization, solvothermal reduction and the like for preparing the oxygen-deficient nano material, the preparation method disclosed by the invention adopts a solid-phase molten zinc thermal reduction technology, takes environment-friendly and low-cost zinc powder as a reducing agent, and prepares the oxygen-deficient nano material by utilizing a solid-phase molten zinc thermal reduction process at a mild high temperature; the preparation method has the advantages of simple process, no special requirement on production equipment, processing universality and industrial production compatibility, successfully prepares a series of defect nanometer materials with adjustable oxygen defect concentration, and effectively prolongs the cycle life of the zinc battery by applying the defect nanometer materials to the negative electrode protection of the zinc ion battery.

The invention provides coated SnO and FeOx composite oxide powder and a silver-based composite electric contact material and a preparation method thereof, and the preparation method comprises the following steps: providing stannous mono-sulphate, dissolving, stirring to form a SnSO4 solution, and continuously reacting to obtain a solution A; adding an alkaline reaction solution into the solution A to reach a preset pH value to obtain a precursor solution; performing hydrothermal reaction on the precursor solution; washing and drying a hydrothermal reaction product to obtain SnO powder; the preparation method comprises the following steps: adding FeSO4 or FeCl2 into an aqueous solution containing SnO powder, dissolving, adding H2C2O4 to obtain a precipitate, filtering, separating, and drying; and carrying out vacuum heat treatment on the precipitate to obtain the coated SnO-coated FeOx composite oxide powder. The SnO-coated FeOx composite oxide with a controllable and adjustable valence structure can be formed, and the composite oxide is firstly applied to the field of silver-based composite electric contact, so that the Ag / SnO-coated FeOx composite electric contact material has the performance advantages of low temperature rise, long cycle life and the like in the service process.

The invention provides a composite hard carbon negative electrode material preparation method, which comprises: S1, adding SnCl4. 5H2O to a microcrystalline graphite / phenolic resin hard carbon suspension, and uniformly stirring for 1 h to obtain a mixed solution A; s2, putting the mixed solution A into a high-pressure kettle for hydrothermal reaction, and after the reaction is finished, soaking and washing in deionized water to obtain SnO2 MG / PF hydrogel; and S3, under the protection of inert gas, carrying out evaporation drying treatment on the SnO2 (at) MG / PF hydrogel, and then putting the SnO2 (at) MG / PF hydrogel into a high-temperature furnace for high-temperature treatment to obtain the composite hard carbon negative electrode material. Phenolic resin hard carbon and microcrystalline graphite are compounded and then doped with a certain amount of tin dioxide to obtain the composite hard carbon negative electrode material, and when the composite hard carbon negative electrode material is applied to the sodium-ion battery, the specific capacity, coulombic efficiency, rate and cycle performance of the sodium-ion battery can be improved.

The invention discloses a double-metal gradient diffusion layer modified high-nickel ternary positive electrode material and a preparation method thereof. The preparation method comprises the following steps: filtering and uniformly dispersing high-nickel ternary positive electrode material powder; introducing inert gas into the atomic layer deposition system, and raising the temperature to a target temperature; respectively preheating the metal precursors A and B to proper temperatures; the preparation method comprises the following steps: sequentially introducing a metal precursor A, precursor water, a metal precursor B and precursor water into a reaction chamber, alternately depositing according to a pulse-reaction-purging sequence, and repeatedly circulating the process to obtain the bimetallic oxide coated high-nickel ternary positive electrode material, and post-annealing treatment. According to the bimetal gradient diffusion layer modified high-nickel ternary positive electrode material prepared by the preparation method disclosed by the invention, the lithium storage performance of the high-nickel ternary material is greatly improved, excellent cycling stability and rate capability are obtained, the coating layer is accurate and controllable, the preparation process is simple, meanwhile, large-batch production can be realized, and relatively high application value is achieved.

The invention discloses a palladium-doped Ir-Sn oxide titanium anode with high catalytic activity and a preparation method of the palladium-doped Ir-Sn oxide titanium anode, and belongs to the technical field of electrolytic anodes. The anode comprises a titanium substrate, a TiO2-Ta2O5 intermediate layer and an Ir-Sn-Pd oxide catalyst layer, the molar ratio of Ir to Sn to Pd in the catalyst layer is (5-6): 3: (1-2), and the total metal ion concentration is 0.3 mol L. The preparation method is realized through titanium substrate pretreatment (sand blasting and etching), intermediate layer coating sintering (a TiCl4-TaCl5 solution) and catalyst layer circulating coating sintering (an H2IrCl6-SnCl4-PdCl2 mixed solution). The relatively cheap palladium element is introduced, the electron structure of the catalyst layer is optimized by utilizing the defect effect, the charge transfer resistance is reduced to 6.7 omegacm, and meanwhile, the iridium consumption is reduced by more than 30%. Experiments show that the cell voltage of the anode is stabilized at 0.95 V (the current density is 5Acm <-2 >), the accelerated life reaches 1630 hours, the coating binding force is 62N, and the corrosion rate in an acidic electrolyte is only 0.01 mm / year. Compared with a traditional iridium tantalum anode, the cost is reduced by 40%, and the overpotential in the oxygen evolution reaction is as low as 0.45 V.

The invention discloses a preparation method and application of a peptide microtube / SnO2 / Au composite gas-sensitive material. The three-dimensional network structure of the peptide microtube is utilized to effectively adsorb SnO2 and Au nanoparticles, so that the SnO2 and Au nanoparticles form a complete connection path on the surface of the peptide microtube, and electron transfer is facilitated; and gas diffusion is also facilitated. The localized surface plasmon resonance (LSPR) effect of Au nanoparticles can enhance visible light absorption and surface reaction activity, so that the gas-sensitive property is improved, and rapid adsorption and desorption reaction can be carried out at room temperature. The prepared sensor exerts the synergistic effect of the three materials, realizes efficient detection of NO2 at room temperature, has very high selectivity to NO2, and has relatively high response to low-concentration NO2, so that trace detection can be carried out.

The invention provides a preparation method of nano indium tin oxide powder, and belongs to the technical field of preparation of electronic ceramic transparent oxide functional inorganic materials. The preparation method comprises the following steps: in an oxygen-containing environment, performing electric arc gasification on an indium tin metal melt, and oxidizing metal steam generated by the electric arc gasification to obtain the nano indium tin oxide powder, the current applied for generating the electric arc is 500 to 1200 A, and the voltage is 50 to 120 V. The preparation method provided by the invention is simple, the oxidation reaction time is short, no exhaust gas is discharged, and meanwhile, the problems of wastewater and waste acid discharge and difficult impurity removal caused by addition of strong acid are avoided. The preparation method provided by the invention can realize continuous production and is high in production efficiency; and the particle size D50 of the prepared nano indium tin oxide powder can be kept to be less than 0.5 mu m and D90 is less than 1 mu m.

The invention discloses a nitric acid type system tin stripping liquid centralized recovery treatment process which comprises the following steps: firstly, adding a cationic coagulant into a nitric acid type tin stripping waste liquid, filtering through a 5-micron filter membrane, discharging into a reaction kettle, and adding a H2O2 solution with the concentration of 5-10%; the pH is adjusted to 2.0-2.5, and copper is removed under the condition of 40-50 DEG C; when the pH value is increased from 2.5 to 3.0-3.5, iron is removed; adjusting the pH value to 13.0-13.5, heating to remove aluminum, and separating to obtain a filtrate containing Na2SnO3; adjusting the pH value of the filtrate to 6.0-6.5, heating to 70-75 DEG C for reaction, and then carrying out gradient cooling to room temperature to generate Sn (OH) 4 precipitate; and centrifugally separating the mixed solution to obtain a tin-containing solid and a tin stripping regenerated solution, and firing the tin-containing solid to obtain a tin dioxide solid. Compared with a traditional process, copper is removed firstly, then iron is removed, aluminum is finally removed, and directional removal is achieved through the difference of precipitation conditions.

The invention relates to the field of materials, and discloses a three-dimensional graphene / metal oxide composite pellet and a preparation method and application field thereof, the three-dimensional graphene / metal oxide composite pellet comprises a graphene pellet and a metal oxide loaded on the graphene pellet; wherein the specific surface area of the three-dimensional graphene / metal oxide composite sphere is 50-500m < 2 > / g. In the obtained three-dimensional graphene / metal oxide composite sphere, the metal oxide is uniformly loaded on the surface of the graphene sphere, and the sphere internally has a rich pore structure, so that the application of gas sensing, catalysis, energy storage and the like is facilitated.

Disclosed are a doped colloidal metal oxide quantum wire and a preparation method thereof, a gas sensor, a gas sensor array, and use thereof, which relate to the technical field of gas sensors. In the preparation method, a main metal precursor, a doped metal precursor, an alcohol solvent, and a fatty acid surfactant are mixed, and a resulting mixture is subjected to a solvothermal reaction, to obtain the doped colloidal metal oxide quantum wire, wherein a main metal element in the main metal precursor is selected from Sn, Zn, W, In, Mo, Fe, Co, Ni, and Cu; a doped metal element in the doped metal precursor is selected from V, Nb, Ta, Cr, Mo, W, Mn, Fe, Co, Ni and Cu; the doped metal element is different from the main metal element; and the solvothermal reaction is performed at a temperature of 150-300° C.

The invention discloses a preparation method of a composite material, the composite material, a photoelectric device and a display device. The preparation method of the composite material comprises the following steps: providing a precursor solution, wherein the precursor solution comprises Mxene, a metal cation source and a first solvent; carrying out hydrothermal treatment to obtain an inorganic semiconductor particle / Mxene composite material solution; the inorganic semiconductor particle / Mxene composite material solution is subjected to microwave treatment, the composite material is obtained, and the composite material comprises inorganic semiconductor particles and Mxene quantum dots. According to the preparation method of the composite material, the inorganic semiconductor particles and the Mxene quantum dots have relatively strong electric field stability, so that the photoelectric device comprising the inorganic semiconductor particles and the Mxene quantum dots has relatively good luminescence performance.

The invention belongs to the technical field of electronic components, and provides a xylene gas sensor based on a Co3O4 and In2O3 heterojunction, and a preparation process and application thereof. The xylene gas sensor comprises a gas sensitive material and an alumina ceramic tube, wherein the gas sensitive material is coated on the surface of the alumina ceramic tube. The gas sensitive material is a nano composite material formed by cobaltosic oxide and indium trioxide. The method is simple in production process, and the obtained gas-sensitive material shows relatively high sensitivity and rapid response and recovery to xylene. Due to the fact that a gas sensor with related achievements is too high in lower limit of detection of to-be-detected gas, the detection performance in a low-concentration environment is not ideal enough. According to the invention, the lower detection limit of the gas sensor can be greatly reduced, and the gas sensor still has obvious response under the concentration of 0.1 ppm, so that xylene in a gas environment can be timely found and protected.

The invention discloses a preparation method of an alpha-Fe2O3 / SnO2 nanoneedle heterojunction gas sensitive material, and belongs to the technical field of preparation and application of inorganic composite materials. Adding a mixed solution of ferric chloride and sodium sulfate and the ceramic tube into a reaction kettle, carrying out hydrothermal reaction at 120-160 DEG C for 10-14 hours, taking out the ceramic tube after the reaction is finished, drying and annealing to obtain a ceramic tube loaded with alpha-Fe2O3 nanoneedles; dissolving tin chloride and urea in water to obtain a mixed solution, adding the mixed solution and the ceramic tube loaded with the alpha-Fe2O3 nanoneedle into a reaction kettle, carrying out hydrothermal reaction at 80-100 DEG C for 1-6 hours, taking out the ceramic tube after the reaction is finished, drying and annealing to obtain the alpha-Fe2O3 / SnO2 nanoneedle composite gas-sensitive material. The preparation method is simple, the product is high in crystallinity and good in stability and is suitable for preparing a high-economical gas sensitive sensor material, and a sensor prepared from the alpha-Fe2O3 / SnO2 nanoneedle heterojunction gas sensitive material can effectively improve the gas sensitive performance of alpha-Fe2O3 and shows an extremely high response value to NO2 while the working temperature is reduced.

The invention provides a Bi-doped SnO catalyst and a preparation method and application thereof, a gas diffusion electrode and a preparation method and application thereof, and belongs to the technical field of catalyst preparation. The preparation method comprises the following steps: mixing divalent metal tin salt, a regulator and bismuth salt in water to obtain a mixed solution; and mixing the mixed solution with a sodium hydroxide solution, and reacting to obtain the Bi-doped SnO catalyst. The preparation method is simple, rapid, low in cost, green and free of organic solvent or high-temperature treatment, and the prepared catalyst is stable in structure and lasting in performance. The Faraday efficiency of a gas diffusion electrode prepared by adopting the Bi-doped SnO catalyst for synthesizing formic acid through electrocatalytic reduction of CO2 at-850 mA / cm < 2 > is as high as 98%, the gas diffusion electrode can stably run for more than 140 h under N2 purging in a solid electrolytic tank, and the concentration of formic acid continuously produced exceeds 5 mol / L.

The invention discloses a negative electrode material for improving the cycle performance of a lithium battery, a preparation method of the negative electrode material, a negative electrode plate and a battery, and the preparation method comprises the following steps: S1, growing SnO2 on a carbon nanotube through a hydrothermal synthesis method to form a one-dimensional composite material SnO2 (at) CNT; s2, Zr ions and a silane coupling agent are introduced into the one-dimensional composite material SnO2 (at) CNT, and the modified SnO2 (at) CNT material is obtained. According to the invention, the cycle life of the lithium battery using the stannic oxide negative electrode material is prolonged through material composite modification.

The invention provides a SnO2 / expanded graphite composite material as well as a preparation method and application thereof, belongs to the technical field of sodium ion batteries, and aims to solve the technical problems of low specific capacity of expanded graphite and unstable SnO2 cycle performance. The preparation method of the SnO2 / expanded graphite composite material comprises the following steps: (1) mixing expandable graphite, soluble tin salt and a solvent to obtain a mixed solution; (2) evaporating the mixed solution to dryness to obtain a graphite intercalation compound; and (3) carrying out microwave heating on the graphite intercalation compound to obtain the SnO2 / expanded graphite composite material. The SnO2 / expanded graphite composite material prepared by the invention is used as a sodium-ion battery negative electrode material, can effectively overcome the defect of poor capacity when a carbon material is independently used and the defects of low conductivity and poor cycle performance when SnO2 is independently used, can synergistically exert the sodium storage advantages of the metal oxide and the expanded graphite, makes up the respective defects, and can be used for preparing the sodium-ion battery negative electrode material. Therefore, the electrochemical performance of the sodium-ion battery is improved.

The invention discloses a preparation method and application of a nano heat-insulating metal oxide composite coating. The preparation method comprises the following steps: preparing a nano ATO crystal of which the surface contains silicon hydroxyl; preparing polymerizable ATO (antimony tin oxide) nano particles; and uniformly mixing the polymerizable ATO nano particles, the silane modified nano silicon dioxide, the self-emulsifying polyurethane emulsion and the auxiliary agent to obtain the required coating. Nanometer ATO crystallization and surface silicon hydroxyl modification are synchronously completed in a hydrothermal environment, and the problem of uneven coating caused by traditional two-step modification is solved; after the high-temperature reaction, cold ethanol is used for realizing shock cooling to stop crystal growth, so that the problem of thermodynamic instability of the nanocrystalline is solved; the interfacial compatibility is improved by introducing a vinyl-containing siloxane monomer; by compounding the polymerizable ATO nano particles, the silane modified nano silicon dioxide, the self-emulsifying polyurethane emulsion and the auxiliaries, a stable topological structure connected by covalent bonds is constructed, and the aging resistance, the heat insulation property and the adhesive force of the coating are remarkably improved.

The invention discloses a nitrogen plasma vapor deposition modified metal oxide catalyst and a preparation method and application thereof.The preparation method of the catalyst comprises the steps that tin salt, CTAB and ammonia water serve as raw materials, SnO2 is prepared through a solution gel method, then the preliminarily-prepared SnO2 is calcined in the air atmosphere, purer SnO2 is prepared, and the catalyst is used for preparing the metal oxide catalyst. And finally, carrying out chemical vapor deposition modification on SnO2 by utilizing high-energy-state N * plasma to prepare the catalyst. The nitrogen-doped tin dioxide catalyst is synthesized on the basis of a chemical vapor deposition method strategy, and the catalyst shows extraordinary performance of electrocatalytic oxygen reduction for synthesis of hydrogen peroxide in an alkaline medium, has good stability and a wide potential window, and has potential application prospects in the field of electrochemical preparation of hydrogen peroxide.