27 results about "Hydrothermal deposition" patented technology

The invention belongs to the technical field of metal material surface modification, and particularly relates to a magnesium alloy surface conductive corrosion-resistant coating and a preparation method, the conductive corrosion-resistant coating comprises a three-layer structure, the total coating thickness is 33-50 microns, the bottom coating is a low-porosity MAO coating prepared through a micro-arc oxidation method, and the thickness is 20-35 microns; the middle coating is a conductive nano-particle layer prepared by adopting a negative pressure mode; and the top coating is a zinc aluminum oxide conductive layer prepared by adopting a vapor-phase hydrothermal deposition method, and the thickness of the top coating is 13-15 microns. In addition, the invention provides the modified magnesium alloy with the conductive corrosion-resistant coating prepared on the surface, the self-corrosion current density of the modified magnesium alloy is 0.18-1.8 * 10 <-7 > A / cm < 2 >, and the volume resistivity of the modified magnesium alloy is 1.30-5.21 * 10 < 4 > omega.m.

The invention provides a high-voltage-resistant polysilazane-based insulating material for a power battery pack of a new energy automobile and a preparation method of the high-voltage-resistant polysilazane-based insulating material, and belongs to the technical field of insulating materials. The silicon carbide microspheres are prepared through reaction of polycarbosilane and polyaniline, and through hydrothermal deposition of molybdenum disulfide and coating of organic boron, the heat-conducting property, the electrical insulating property and the flame retardant property of the silicon carbide microspheres are improved; secondly, the prepared metal organic supramolecular cage is subjected to carbon nitride modification and surface modification, so that the thermal conductivity, the interface bonding force and the dielectric property of the metal organic supramolecular cage are improved; in addition, the carbon nanotubes are subjected to acid treatment, rare earth lanthanum modification and boron nitride compounding, so that the dispersity, the thermal conductivity and the insulating property of the carbon nanotubes are remarkably improved; through the synergistic effect of all the components, the thermal performance, the electrical performance and the mechanical performance of the composite material are comprehensively optimized.

The invention provides a recycling method of waste polyester alcoholysis byproducts, which comprises the following steps: S1) mixing porous boron nitride micro powder, crown ether and water, carrying out hydrothermal deposition treatment, and freeze-drying to obtain a solid powdery material; carrying out ball milling on the solid powdery material to obtain a porous boron nitride and crown ether hybrid material; and S2) carrying out alcoholysis reaction on waste polyester, ethylene glycol and a catalyst potassium carbonate, and adding the hybrid material into the obtained reaction liquid. The invention also provides a preparation method of the porous boron nitride and crown ether hybrid material. In the recycling method of the waste polyester alcoholysis by-product, the introduction of the porous boron nitride and crown ether hybrid material combines the strong adsorbability of metal ions of porous BN and the selective metal complexation of crown ether, so that the removal rate of potassium ions in the alcoholysis reaction liquid is increased; the molecular chain end-capping effect caused by potassium ions in the subsequent polymerization process of a depolymerization product is overcome, and the method has important industrial application value.

The application provides a surface-coated anti-corrosion dioxin-resistant silicon carbide wear-resistant powder material, and relates to the technical field of silicon carbide materials. The material takes cubic crystal type beta-SiC nano powder as a matrix, realizes the combination of high-temperature corrosion resistance, high wear resistance and high-efficiency dioxin prevention by constructing a gradient coating structure of 'Si-O-C transition layer / ZrO2-Al2O3-Y2O3 middle layer / SiO2-rare earth oxide-phosphotungstic acid multifunctional outer layer'. The preparation method of the material comprises key steps of matrix etching, transition layer construction, hydrothermal deposition and atmosphere calcination, and the process is controllable and has good repeatability. The obtained powder has excellent long-term protection performance, good dispersibility and stable structural integrity, and is suitable for fields of wear-resistant coating, composite reinforcement and waste gas treatment in harsh environments.

The application discloses a kind of foam nickel load iron nickel bimetallic phosphide heterojunction catalyst and its preparation method and application, belong to electrocatalytic material technical field.The application is in situ grown by hydrothermal deposition in combination with low-temperature phosphorization process, and is prepared on foam nickel base Phosphide iron / Phosphide nickel heterojunction catalyst (Fe2P / Ni2P@NF).The prepared catalyst shows excellent performance in the electrocatalytic reduction of nitrate synthesis ammonia and high nitrate wastewater degradation.The preparation process of the catalyst of the application is simple, low in cost, and little to environmental pollution, and the self-supporting electrode prepared by integration can be directly applied to proton exchange membrane electrolytic cell, and has wide application prospect.

The present invention proposes a preparation method, product and application of a flower-shaped carbon-based Mn-doped NiCoP thin film electrode material, which belongs to the field of electrochemical technology. The flower-shaped carbon-based Mn-doped NiCoP thin film electrode material of the present invention is deposited on a growth substrate by a hydrothermal deposition method to prepare a three-dimensional walnut shell-derived porous carbon-based Mn-doped NiCo precursor, and then the three-dimensional walnut shell-derived porous carbon-based Mn-doped NiCo precursor is prepared by phosphating using a gas-solid reaction method. WSC‑N / O and Mn elements are introduced during the preparation process to enhance the electrochemical activity and electronic conductivity, thereby realizing the rapid transmission of electrons and improving the electrochemical properties of the electrode material, and it is further used in the preparation of high-performance supercapacitors and aqueous zinc ion batteries, showing excellent energy density. The introduction of the electrode material of the present invention provides a new method for designing and manufacturing high-performance energy storage devices.

The invention relates to a simulated protein structure catalyst as well as a preparation method and application thereof. A hydrophobic porous carbon / carbon material which is low in cost and easy to obtain is selected, and a hydrophilic layered hydroxide (LDHs) nanosheet with a three-dimensional structure is constructed on the carbon surface through simple hydrothermal deposition, so that the protein-imitating multifunctional structure composite carrier is formed. The high-activity catalytic component is deposited on the LDHs nanosheet through simple chemical deposition, the high-activity advanced oxidation catalyst is obtained, the problems that an existing advanced oxidation catalyst is large in oxidizing agent demand, low in low-concentration pollutant removal rate and insufficient in removal rate are solved, and actual production, popularization and application are better facilitated.

This invention belongs to the field of water electrolysis application technology, and relates to a high-entropy hydroxy oxide for water electrolysis and its preparation method. It can be used in the field of alkaline water electrolysis and has a significant catalytic effect on hydrogen production from alkaline water electrolysis, greatly reducing the cost of electrode preparation. It is prepared by hydrothermal deposition coupled with electrochemical reconstruction to obtain a watermelon seed-shaped co-hydroxy oxide of Fe, Co, Ni, Cu and Mo with a thickness of 0.3-1.0 μm. The specific steps of the hydrothermal deposition coupled with electrochemical reconstruction preparation method are as follows: Step (1): A certain amount of iron salt, cobalt salt, nickel salt, copper salt and citric acid are added to a mixed solution of water and ethanol. Under stirring, an aqueous solution of molybdate is added, and a molybdenum-based composite oxide is obtained by hydrothermal deposition. Step (2): The molybdenum-based composite oxide obtained in step (1) is subjected to electrochemical treatment. The molybdenum-based composite oxide is electrochemically reconstructed into a high-entropy hydroxy oxide, named FeCoNiCuMoOOH.

The invention discloses a zinc sulfide and graphdiyne nano composite material for mercury vapor adsorption removal, a preparation method and application, zinc sulfide is attached to the surface of graphdiyne in a nanoparticle state, and the preparation method is as follows: zinc sulfide is attached to the surface of graphdiyne in the nanoparticle state through a hydrothermal method. The invention aims to provide a zinc sulfide and graphdiyne nanocomposite for adsorbing and removing mercury vapor as well as a preparation method and application of the zinc sulfide and graphdiyne nanocomposite, so that the mercury vapor is efficiently removed through the zinc sulfide and graphdiyne nanocomposite.

The invention discloses a high-temperature-resistant soft magnetic powder core material and a preparation method thereof. The high-temperature-resistant soft magnetic powder core material comprises iron-based magnetic powder and a composite insulating coating, the composite insulating coating is of a gradient structure and sequentially comprises an amorphous iron phosphate transition layer, a lithium aluminum oxide layer embedded with nano zirconium oxide particles and a sodium silicate film layer from inside to outside. According to the preparation method, firstly, iron-based magnetic powder is pretreated, then passivated powder is prepared through magnetic field-assisted hydrothermal deposition, then coated powder is prepared through a sol-gel method, and finally, the high-temperature-resistant soft magnetic powder core material is obtained through rotary heat treatment. The high-temperature resistance of the soft magnetic powder core material can be optimized, and the resistivity, compactness and high-temperature stability of the insulating coating film layer are improved, so that the loss of the powder core material is reduced, and the quality reliability of the powder core material is improved.

The present invention provides a method for recycling by-products of waste polyester alcoholysis, comprising the following steps: S1) Mix porous boron nitride micropowder, crown ether and water, perform hydrothermal deposition treatment and then freeze-dry to obtain a solid powder material; ball-mill the solid powder material to obtain a porous boron nitride@crown ether hybrid material; S2) Perform an alcoholysis reaction on waste polyester, ethylene glycol and a catalyst potassium carbonate, and add the hybrid material to the obtained reaction solution. The present application also provides a preparation method of the porous boron nitride@crown ether hybrid material. In the method for recycling by-products of waste polyester alcoholysis of the present application, the introduction of the porous boron nitride@crown ether hybrid material combines the strong metal ion adsorption property of porous BN with the selective metal complexation of crown ether, improves the removal rate of potassium ions in the alcoholysis reaction solution, overcomes the molecular chain capping effect caused by potassium ions in the subsequent polymerization process of the depolymerization product, and has important industrial application value.

The invention provides a preparation method of a red-mud-based photoelectrode and application of the red-mud-based photoelectrode in photoelectrocatalysis, and belongs to the technical field of solid waste resource utilization and photoelectrocatalysis. Industrial solid waste red mud is used as a raw material, a precursor solution is obtained through acid digestion treatment, a solution system is optimized by regulating and controlling the pH value, a thin film grows on a substrate material through the hydrothermal deposition technology, and finally the red mud-based photoelectrode is obtained through high-temperature calcination. The method adopted by the invention is simple and convenient in process and low in raw material cost, iron-based components such as Fe2O3 rich in the red mud can be efficiently activated, and in-situ doping and structure regulation and control of various metal elements are realized. The prepared red mud-based photoelectrode can be applied to the field of photoelectrocatalysis, including hydrogen production through water decomposition, biomass conversion, solid waste recycling and the like. According to the method, waste is treated with waste as the core, a new way is opened up for comprehensive utilization of the red mud solid waste, and the method has good application potential in the fields of environment and energy.

According to the method, an auxiliary solvent N, N-dimethylacetamide (DMAC) is added into a precursor solution for hydrothermal deposition of the antimony sulfide thin film to adjust the deposition rate, so that the thickness of the thin film is optimized, the morphology of the thin film is improved, the crystallinity is improved, the defect density of the thin film is reduced, and the performance of a device is improved. The antimony sulfide solar cell comprises a conductive substrate (including FTO and the like), an electron transport layer, an antimony sulfide solar cell absorption layer and a counter electrode. The DMAC can promote grain polymerization of the antimony sulfide thin film, increase the grain size and reduce electric leakage channels of the solar cell. And DMAC has the effect of adjusting the deposition rate, so that the reaction is slower to obtain a more appropriate thickness of the absorption layer. By constructing an effective antimony sulfide thin film solar cell structure, the device performance of the antimony sulfide solar cell is improved.

The invention discloses a C / C-based tungsten nitride / bismuth tungstate composite material and a preparation method and application thereof.The preparation method comprises the steps that WN and Bi2WO6 are placed in the same beaker, then an isopropanol solution is added, stirring is conducted till the WN and the Bi2WO6 are evenly dispersed, then iodine is added, stirring continues to be conducted till the mixture is even, and a deposition solution is obtained; the preparation method comprises the following steps: pre-treating a C / C substrate, fixing the pre-treated C / C substrate on a negative electrode of hydrothermal electrophoretic deposition equipment, then putting the pre-treated C / C substrate in a deposition solution F, heating a hydrothermal deposition kettle, applying voltage to carry out electrophoretic deposition, putting a self-supporting sample after deposition into a drying oven for drying to finally obtain a C / C-WN / Bi2WO6 photoelectrode material, and synthesizing a WN / Bi2WO6 heterojunction on the C / C substrate to be used as a photoanode. Tungsten nitride is used as the electron transport layer, photo-induced electrons generated by light absorption of bismuth tungstate can be transmitted to the C / C substrate and then transmitted to the photocathode, the structure is beneficial to reduction of recombination of photo-induced carriers, and then the photoelectrocatalysis performance of bismuth tungstate is improved.

The utility model discloses a simple quartz support for a laboratory, which relates to the technical field of supports, solves the technical problems of simplicity and stability, and comprises a first side plate, columnar quartz is fixedly mounted on one side of the first side plate, and a second side plate is fixedly mounted at one end, far away from the first side plate, of the columnar quartz. Grooves are formed in the sides, close to the columnar quartz, of the first side plate and the second side plate, supporting pieces are installed at one ends of the first side plate and the second side plate, and limiting assemblies are arranged on the first side plate and the second side plate. The device is simple in structure, low in material cost, simple to prepare and convenient to use, is used for the hydrothermal deposition reaction, not only can fix a reaction substrate, but also can multiply the effective hydrothermal deposition reaction area, and greatly improves the reaction efficiency.

The invention discloses an ion selective groundwater remediation system and method based on a composite adsorption material, the system comprises an in-situ PRB module, an ex-situ packed bed module and a regulating reservoir, the in-situ PRB module and the ex-situ packed bed module are both internally provided with the composite adsorption material; the composite adsorption material is composed of, by mass, 60-80% of a biochar matrix, 10-20% of a nanometer iron oxide load layer and 10-20% of a modified zeolite coating, the preparation method of the composite adsorption material comprises the steps of pyrolysis, hydrothermal deposition and surface modification, the system adopts an acid pickling-organic solvent elution-thermal regeneration combined process as a regeneration process, and the composite adsorption material is prepared through the following steps: preparing the composite adsorption material; the material cost is reduced by 40%, the adsorption capacity is improved by 3-5 times, the adsorption effect is greatly improved through twice treatment, heavy metal / organic pollution synchronous removal is achieved through the component synergistic effect, the recovery process is simplified through the magnetic separation technology, and the operation and maintenance cost is reduced.

The invention discloses a preparation method of a spherical Co3O4-coated Cu3Mo2O9 nano-film electrode material, and belongs to the technical field of electrode materials. The preparation method comprises the following steps: firstly, taking foamed nickel as a template, generating Co3O4 on the foamed nickel in situ through a hydrothermal reaction, then adding Cu (NO3) 2.6 H2O and NaMoO4 into deionized water to obtain a uniform solution, soaking the Co3O4 generated on the foamed nickel in situ into the uniform solution, and successfully preparing the Co3O4-coated Cu3Mo2O9 film electrode material on the foamed nickel by adopting a simple hydrothermal deposition method. The electrode material shows excellent electrochemical performance.

The present invention provides a high-voltage polysilazane-based insulating material for new energy vehicle power battery packs and a preparation method thereof, belonging to the technical field of insulating materials. The present invention prepares silicon carbide microspheres by reacting polycarbosilane with polyaniline, and improves their thermal conductivity, electrical insulation and flame retardancy through hydrothermal deposition of molybdenum disulfide and organic boron coating. Secondly, the prepared metal organic supramolecular cage is modified by carbon nitride and surface modification to improve its thermal conductivity, interfacial bonding force and dielectric properties. In addition, carbon nanotubes are treated with acid, modified with rare earth lanthanum and composited with boron nitride to significantly improve their dispersibility, thermal conductivity and insulation properties. The synergistic effect between the various components comprehensively optimizes the thermal, electrical and mechanical properties of the composite material.

The invention discloses a VC / BiVO4 / CC self-supporting photoelectrocatalytic material and a preparation method and application thereof.The preparation method includes the steps that BiVO4 / CC is prepared through a hydrothermal deposition method, VC powder is prepared through a one-step calcination method, VC grows on the BiVO4 / CC through a slurry coating method to prepare the VC / BiVO4 / CC self-supporting photoelectrocatalytic material, a unique heterostructure is formed between BiVO4 and VC, and the photocatalytic performance of the material is improved. The structure can strengthen the electron interaction of a two-phase heterogeneous interface, electron transmission is facilitated, VC has good conductivity, and the overall conductivity of the material can be improved after compounding; biVO4 and VC are compounded on a CC substrate, electron transmission can be further effectively enhanced, meanwhile, CC is resistant to acid and alkali, the VC / BiVO4 / CC self-supporting photoelectrocatalysis material can have good stability under different conditions, and the prepared VC / BiVO4 / CC self-supporting photoelectrocatalysis material has high conductivity, excellent reaction kinetic characteristics, high stability and efficient hydrogen evolution capacity; great application potential is shown in the field of photoelectrocatalysis.

The invention discloses an In2S3-CeO2 / HZSM-5 bifunctional catalyst and an application of the In2S3-CeO2 / HZSM-5 bifunctional catalyst in separation of guaiacol and veratrole. The catalyst is prepared by loading a visible light responsive In2S3-CeO2 heterojunction on an HZSM-5 molecular sieve subjected to pore expansion and surface modification by ammonium nitrate through a hydrothermal-deposition method. The shape-selective adsorption effect of the HZSM-5 molecular sieve can preferentially enrich guaiacol molecules, and the In2S3-CeO2 heterojunction can efficiently activate oxygen to generate active oxygen species under the irradiation of visible light, so that the adsorbed guaiacol is subjected to selective in-situ photocatalytic degradation immediately, and the guaiacol is gradually mineralized into CO2 and H2O. Through the synergistic effect of photocatalysis and adsorption, guaiacol is efficiently and selectively removed, so that the separation selectivity and the purification efficiency of the veratrole product are remarkably improved.

A method for preparing an electromagnetic shielding absorbing material is to prepare biomass-derived tubular carbon fibers using cotton fibers as raw materials, and then hydrothermally deposit MoS2 on the surface of the biomass-derived tubular carbon fibers to form a C / MoS2 composite structure in which MoS2 wraps the tubular carbon fibers. The material has excellent electromagnetic wave shielding performance. After being made into an absorbing coating, it has a low reflection loss value of ‑41.7 dB in the frequency range of 2 to 18 GHz. The electromagnetic shielding absorbing material C / MoS2 prepared by the present invention can be applied to various equipment and products that require electromagnetic shielding in life and work, such as shale gas mining equipment, mining machinery and equipment, medical instruments, and aerospace equipment, thereby reducing the interference of electromagnetic waves on the normal operation of various equipment. In addition, it can be used in military equipment to achieve a shielding function by absorbing electromagnetic waves.

The invention relates to an efficient photocatalytic water splitting hydrogen production material based on a plasmon enhancement mechanism and a preparation method of the efficient photocatalytic water splitting hydrogen production material. The material is characterized in that a porous TiO2 nanotube array is used as a matrix, the tube diameter is 50-200 nm, and the wall thickness is 10-50 nm; au-Ag bimetallic nano-particles with the particle size of 5-20 nm are loaded on the surface, the molar ratio of Au to Ag is 1: 3-3: 1, and the Au-Ag bimetallic nano-particles are used for exciting the surface plasmon resonance effect; further depositing a two-dimensional MoS2 nanosheet as a co-catalyst on the outer surface, wherein the thickness of the two-dimensional MoS2 nanosheet is 1-5nm; and an ultrathin carbon layer with the thickness of 1-3nm is deposited on the whole surface so as to improve light absorption and stability. The invention further provides a preparation method of the photocatalytic material. The preparation method sequentially comprises the steps of TiO2 anodic oxidation, MoS2 hydrothermal deposition, metal nanoparticle photodeposition, CVD carbon layer coating and the like. The prepared material shows excellent hydrogen yield and stability under the driving of sunlight, and has a wide application prospect of photocatalytic hydrogen production.

The invention discloses a method for separating total iron elements in 300-series stainless steel sulfuric acid etching waste liquid. The method comprises the following steps: adding an alkaline substance into the stainless steel sulfuric acid etching waste liquid to adjust the pH value; wherein iron ions in the stainless steel sulfuric acid etching waste liquid comprise Fe < 2 + > and Fe < 3 + >; adding an oxidizing agent into the system for reaction to oxidize ferrous ions into ferric ions until the concentration of Fe < 2 + > in the system is less than or equal to 1g / L; adding an alkaline substance and / or a coprecipitation substance to adjust the pH value, so that ferric ions are separated out in a precipitation form; and separating the generated precipitate to respectively obtain filter residues and filtrate, washing the filter residues until the concentrations of Ni < 2 + > and Cr < 3 + > are lower than 0.01%, and combining the obtained washing liquid with the filtrate to complete the separation of the total iron element in the stainless steel sulfuric acid etching waste liquid. According to the method, the iron element in the etching waste liquid can be separated from the etching liquid by utilizing methods of chemical oxidation, hydrothermal deposition, physical separation and the like, so that the recycling of the total iron element is realized.

The invention discloses a magnetic-hydrophobic bifunctional pearlife heat insulation material and a preparation method thereof. The preparation method comprises the following steps: taking expanded perlite as a matrix, and constructing a core-shell structure step by step through a sol-gel method: firstly, in an acidic environment with the pH value of 3-5, taking 0.2-0.4 mol / L of FeCl3. 6H2O and FeCl2. 3H2O as precursors, forming a Fe3O4 magnetic inner layer with the thickness of 50 + / -5nm through hydrothermal deposition, and realizing magnetic suspension response within 20s under the magnetic field intensity of 0.5-1.5 T; taking tetraethoxysilane (TEOS) and fluorosilane as raw materials, and roasting at 400 + / -10 DEG C to form a water contact angle gt; and a SiO2 super-hydrophobic shell at 150 DEG C can effectively block water molecule permeation. The obtained material has magnetic control positioning and super-hydrophobic characteristics, keeps stable heat insulation performance in a liquid hydrogen environment at the temperature of-253 DEG C, overcomes the problem of low-temperature heat insulation failure caused by moisture permeation of traditional pearlife, and is suitable for a low-temperature liquid storage tank system.

The invention mainly researches and utilizes a post-selenylation method to improve the energy band arrangement of the antimony sulfide solar cell. Firstly, proper raw materials and solvents are selected, antimony potassium tartrate hemihydrate and sodium thiosulfate pentahydrate are used as precursor materials of Sb and S, and an antimony sulfide thin film is prepared through a hydrothermal deposition method. And carrying out energy band engineering treatment on the surface of the antimony sulfide film. The influence of energy band engineering processing on the aspects of thin film morphology, crystal structure, band gap, energy level position and the like is researched. Under the condition of energy band engineering treatment, the crystallinity of the thin film is improved, crystal grains are increased, the morphology of the antimony sulfide thin film is improved, the energy level orientation is good, compared with a control group treated by the energy band engineering, the photoelectric conversion efficiency is remarkably improved, and no other impurities are introduced into the final absorption layer thin film.

The invention discloses a stainless steel loaded cobalt-nickel bimetallic phosphide catalyst, a preparation method thereof and application of the stainless steel loaded cobalt-nickel bimetallic phosphide catalyst in electrocatalytic synthesis of ammonia, and belongs to the technical field of electrocatalytic materials. The cobalt phosphide-nickel phosphide catalyst (CoP-Ni2P / SS) is grown in situ on a stainless steel substrate by combining hydrothermal deposition with a low-temperature phosphating process, and the cobalt phosphide-nickel phosphide catalyst shows excellent performance in electrocatalytic nitrate reduction synthesis of ammonia. The preparation method is simple in preparation process, low in cost and small in environmental pollution, and the self-supporting electrode prepared through integrated forming can be directly applied to the proton exchange membrane electrolytic cell and is wide in application prospect.

The invention discloses anti-scouring anhydrous stemming for a blast furnace and a preparation process of the anti-scouring anhydrous stemming, and belongs to the technical field of anhydrous stemming. La (OH) CO3 powder is synthesized on titanium dioxide nanorod powder through a hydrothermal deposition method, precursor composite powder is formed, lanthanum oxide-titanium dioxide composite powder is obtained after calcination, the lanthanum oxide-titanium dioxide composite powder and other raw materials are mixed and ground through a mixing mill, and the anti-scouring anhydrous stemming is obtained. The rod-like structure of the titanium dioxide nanorod powder increases the surface area and provides more attachment sites for lanthanum oxide, and meanwhile, the La (OH) CO3 powder can be decomposed to generate carbon dioxide and water in the high-temperature calcination process, so that pores are increased, the specific surface area is increased, active sites for reaction with hydrogen are increased, and when the titanium dioxide nanorod powder is used as anhydrous stemming in a blast furnace, the specific surface area of the titanium dioxide nanorod powder is increased. When the water-free stemming is used, hydrogen permeating into the water-free stemming can be adsorbed and fixed, methanation reaction between a carbonaceous material in the water-free stemming and the hydrogen is reduced, so that volume expansion is reduced, cracks are avoided, and the density of the water-free stemming is increased.