CN108767268B - Preparation method and application of Cu nanorod-structured catalyst - Google Patents

Preparation method and application of Cu nanorod-structured catalyst Download PDF

Info

Publication number
CN108767268B
CN108767268B CN201810378503.0A CN201810378503A CN108767268B CN 108767268 B CN108767268 B CN 108767268B CN 201810378503 A CN201810378503 A CN 201810378503A CN 108767268 B CN108767268 B CN 108767268B
Authority
CN
China
Prior art keywords
equal
smelting
amorphous alloy
nanorod
structured catalyst
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Active
Application number
CN201810378503.0A
Other languages
Chinese (zh)
Other versions
CN108767268A (en
Inventor
潘冶
陈高
陆韬
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Southeast University
Original Assignee
Southeast University
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Southeast University filed Critical Southeast University
Priority to CN201810378503.0A priority Critical patent/CN108767268B/en
Publication of CN108767268A publication Critical patent/CN108767268A/en
Application granted granted Critical
Publication of CN108767268B publication Critical patent/CN108767268B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/86—Inert electrodes with catalytic activity, e.g. for fuel cells
    • H01M4/88—Processes of manufacture
    • H01M4/8825—Methods for deposition of the catalytic active composition
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B82—NANOTECHNOLOGY
    • B82Y—SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES
    • B82Y40/00—Manufacture or treatment of nanostructures
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/86—Inert electrodes with catalytic activity, e.g. for fuel cells
    • H01M4/90—Selection of catalytic material
    • H01M4/9041—Metals or alloys
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y02E60/30—Hydrogen technology
    • Y02E60/50—Fuel cells

Abstract

The invention discloses a preparation method and application of a Cu nano rod-shaped catalyst, wherein the method comprises the following steps: (1) preparation of CuxZryNizAn amorphous alloy thin strip, wherein x is more than or equal to 25 and less than or equal to 45, y is more than or equal to 20 and less than or equal to 40, z is more than or equal to 30 and less than or equal to 45, and x + y + z is equal to 100; (2) corroding the prepared amorphous alloy strip in hydrofluoric acid solution at a certain temperature for a certain time by using a chemical dealloying method, repeatedly soaking and cleaning the amorphous alloy strip by using deionized water and absolute ethyl alcohol, and drying the amorphous alloy strip to obtain a thin strip with a Cu nano rod-shaped structure on the surface, wherein the thin strip can be directly used as a catalytic electrode. The material prepared by the invention is used for a direct methanol fuel cell anode catalyst, and the current density of the methanol oxidation peak in 1mol/L methanol and 1mol/L potassium hydroxide solution reaches 250mA cm‑2The catalyst has excellent catalytic performance and stability, does not contain noble metal elements, and has simple preparation process.

Description

Preparation method and application of Cu nanorod-structured catalyst
Technical Field
The invention belongs to the technical field of nano materials and electrochemical sensors, and particularly relates to CuxZryNizThe method for preparing the Cu nano rod-shaped electrode by using the amorphous alloy thin strip as a precursor and a chemical dealloying method and the application of the electrode on the anode catalyst of the methanol fuel cell.
Background
Direct methanol fuel cells have been used as an excellent energy converter for flexible electronic devices due to their excellent characteristics of high energy density, high conversion efficiency, convenience in transportation, low pollutant emissions, etc. The oxidation of methanol to carbon dioxide requires a catalyst, which here mainly serves two purposes: one is to promote the cleavage of the C-H bond; secondly, the generated residue is promoted to react with some oxygen-containing groups to generate carbon dioxide. During the oxidation of methanol, the intermediate carbon monoxide formed will bind linearly to the anode, poisoning the anode and thus reducing the active sites of the catalyst. Therefore, to effectively catalyze methanol oxidation, it is important to select a good catalyst.
The Cu catalytic electrode with the nano structure has wide application prospect in the aspects of direct methanol anode catalysts and the like due to the large specific surface area and the relatively low price of copper metal. The chemical dealloying method has the characteristics of simple equipment, simple and convenient operation, low cost, strong controllability and the like. Compared with crystalline alloy, the amorphous alloy has no crystal characteristics such as crystal boundary, segregation and the like, has uniform components, and can be used as a more ideal precursor of a chemical dealloying method to prepare a nanostructure material.
Disclosure of Invention
The technical problem is as follows: the invention aims to provide a preparation method and application of a Cu nanorod-shaped catalyst. The method has simple process, low manufacturing cost, simple operation and easy control of conditions, is easy for industrialized mass production, and can be directly used as the anode catalytic electrode of the methanol fuel cell.
The technical scheme is as follows: the preparation method of the Cu nanorod structure catalyst comprises the following steps of:
step 1: mixing raw materials of pure Cu, pure Zr and pure Ni evenly, and preparing the Cu by utilizing a vacuum arc furnace and high vacuum melt-spun equipmentxZryNizAn amorphous alloy thin strip;
step 2: the obtained CuxZryNizPlacing the amorphous alloy thin strip in hydrofluoric acid solution, and placing at 40-60 ℃ for chemical dealloying;
and step 3: the obtained dealloyed CuxZryNizAnd taking out the amorphous alloy thin strip, repeatedly soaking and cleaning the amorphous alloy thin strip by using deionized water and alcohol in sequence, and drying to obtain the Cu nano rod-shaped catalyst.
Wherein the content of the first and second substances,
the step 1 specifically comprises the following steps:
step 1.1: according to CuxZryNizWeighing the Cu, Zr and Ni element materials according to the target components, and uniformly mixing to obtain a smelting raw material, wherein the purity of each element material is more than 99.9%; wherein x, y and z respectively correspond to the atomic percentage of each alloy element, wherein x is more than or equal to 25 and less than or equal to 45, y is more than or equal to 20 and less than or equal to 40, z is more than or equal to 30 and less than or equal to 45, and x + y + z is 100;
step 1.2: putting the smelting raw material obtained in the step 1.1 into a vacuum arc smelting furnace, smelting under the argon protective atmosphere, continuously smelting after the raw material is molten, stopping heating to enable the alloy to be cooled to be solidified along with a crucible, turning the alloy over, repeatedly smelting, and cooling to obtain a master alloy ingot with uniform components;
step 1.3: crushing the mother alloy ingot obtained in the step 1.2 into small pieces, putting the small pieces of alloy ingot into a quartz tube with an opening diameter of 1-2 mm, placing the quartz tube into an induction coil of vacuum melt-spinning equipment for fixing, adjusting the distance between the quartz tube and a copper roller, closing a cavity, and pumping the cavity to ensure that the vacuum degree of the cavity is less than or equal to 5 multiplied by 10-3Pa, filling inert gas argon as a protective atmosphere, and adjusting the pressure difference between the inside and the outside of the cavity;
step 1.4: melting alloy blocks by adopting induction melting, and spraying alloy liquid in a molten state onto a copper roller rotating at a high speed by utilizing pressure difference to obtain an amorphous alloy thin belt; the smelting temperature is 950-1150 ℃.
The concentration of the hydrofluoric acid solution is 0.8-1.2 mol/L.
The standing time at 40-60 ℃ is 5-72 hours.
The time for continuously smelting the raw materials after the raw materials are melted is 3-8 minutes.
The repeated smelting times are 3-5 times.
The linear speed of the copper roller rotating at a high speed is 25-30 m/s.
In the step 3, the drying is natural drying at room temperature.
The diameter of the Cu nanorod structure obtained in the step 3 is 100-160 nm, and the length of the Cu nanorod structure is 400-480 nm.
The Cu nanorod structure catalyst prepared by the method is applied to a methanol fuel cell anode catalyst.
Has the advantages that: in CuxZryNizThe Cu nanometer rod-shaped structure material prepared on the amorphous alloy thin strip can be directly used as an anode catalytic electrode of a methanol fuel cell.
Compared with other metal nanostructure preparation methods, the method has the advantages of simple process, low manufacturing cost, simple operation, easy control of conditions and easy industrial large-scale production.
The Cu nanorod-shaped electrode prepared by the method can be used for directly catalyzing the oxidation of methanol in an alkaline environment, and has high catalytic performance and stability.
Drawings
FIG. 1 is an XRD spectrum of a thin amorphous alloy strip prepared in the first example.
FIG. 2 is an XRD spectrum of the amorphous alloy thin strip after chemical dealloying in the first embodiment.
FIG. 3 is a Scanning Electron Microscope (SEM) photograph of the strip surface after dealloying in one embodiment.
FIG. 4 is a cyclic voltammogram of the Cu nanorod structured catalyst prepared in example one in a mixed solution of 1.0mol/L methanol and 1.0mol/L potassium hydroxide.
Detailed Description
The invention will be described in further detail with reference to the following examples and the accompanying drawings.
The first embodiment is as follows: the preparation method of the Cu nanorod architecture material in this embodiment is as follows:
step 1: according to Cu30Zr30Ni40Weighing Cu, Zr and Ni with the purity of 99.9 percent according to target components, and uniformly mixing to obtain a smelting raw material;
step 2: putting the smelting raw material obtained in the step 1 into a vacuum arc smelting furnace, smelting under the argon protective atmosphere, continuously smelting for 3-8 minutes after the raw material is molten, stopping heating to enable the alloy to be cooled along with a crucible to be solidified, turning the alloy over, repeatedly smelting for 3-5 times, and cooling to obtain a master alloy ingot with uniform components;
and step 3: crushing the mother alloy ingot obtained in the step 2 into small pieces, putting the small pieces of alloy ingot into a quartz tube with an opening diameter of 1-2 mm, placing the quartz tube into an induction coil of vacuum melt-spinning equipment for fixing, adjusting the distance between the quartz tube and a copper roller, closing a cavity, and pumping the cavity to ensure that the vacuum degree of the cavity is less than or equal to 5 multiplied by 10-3Pa, filling inert gas argon as a protective atmosphere, and adjusting the pressure difference between the inside and the outside of the cavity;
and 4, step 4: melting alloy blocks by adopting induction melting, and spraying alloy liquid in a molten state onto a copper roller rotating at a high speed by utilizing pressure difference to obtain an amorphous alloy thin belt; the smelting temperature is 1100 ℃, and the linear speed of the copper roller is 25 m/s; the XRD pattern of the prepared amorphous alloy thin strip is shown in figure 1, and a remarkably broadened dispersion diffraction peak can be seen from the pattern, and a crystal diffraction peak is absent, so that the alloy thin strip is of an amorphous structure;
and 5: cu obtained in the step 430Zr30Ni40Cutting the amorphous alloy thin strip into strips of about 4cm, weighing 100mg of the strips, placing the strips in 1.0mol/L hydrofluoric acid solution, placing the strips at 50 ℃ for 72 hours, and carrying out chemical dealloying;
step 6: and taking out the thin strip after the alloy is removed, repeatedly soaking and cleaning the thin strip by using deionized water and alcohol in sequence, and drying the thin strip for 24 hours at room temperature to obtain the Cu nanometer rod-shaped structure.
Fig. 2 shows the XRD pattern after thin strip dealloying, which shows that the nanorod surface layer is typically fcc copper structure. The scanning electron microscope picture of the product prepared in the first embodiment is shown in fig. 3, which shows that the product is an obvious nanorod structure, the diameter of the Cu nanorod is 100-160 nanometers, and the length of the Cu nanorod is 400-480 nanometers.
At 1.0M CH3In OH +1.0M KOH solution, a three-electrode system is adopted, the prepared Cu nano rod-shaped structure strip is used as a working electrode, a platinum sheet electrode is used as an auxiliary electrode, an Ag/AgCl electrode is used as a reference electrode, and cyclic voltammetry is used for scanning, so that the Cu nano rod-shaped structure catalyst prepared by the method has a good catalytic effect on methanol oxidation under an alkaline condition as shown in figure 4.
Example two: the difference between the embodiment and the embodiment one is that the atomic percentages of the target components Cu, Zr and Ni in the step 1 are 40:30: 30. The rest is the same as the first embodiment.
Example three: the difference between the present embodiment and the first embodiment is that the atomic percentages of the target components Cu, Zr and Ni in step 1 are 35:30: 35. The rest is the same as the first embodiment.
Example four: the difference between the present embodiment and the first embodiment is that the atomic percentages of the target components Cu, Zr and Ni in step 1 are 25:30: 45. The rest is the same as the first embodiment.
Example five: the difference between the embodiment and the first embodiment is that the concentration of the hydrofluoric acid aqueous solution in the step 5 is 0.5mol/L, and the dealloying time is 48 h. The rest is the same as the first embodiment.
Example six: the difference between the embodiment and the first embodiment is that the concentration of the hydrofluoric acid aqueous solution in the step 5 is 0.5mol/L, and the dealloying time is 72 h. The rest is the same as the first embodiment.
Example seven: the difference between the embodiment and the first embodiment is that the concentration of the hydrofluoric acid aqueous solution in the step 5 is 0.5mol/L, and the dealloying time is 96 h. The rest is the same as the first embodiment.
Example eight: the difference between this example and the first example is that the temperature of the dealloying process in step 5 is 40 ℃. The rest is the same as the first embodiment.
Example nine: the difference between this example and the first example is that the temperature of the dealloying process in step 5 is 60 ℃. The rest is the same as the first embodiment.
The above examples are only preferred embodiments of the present invention, but not limiting the scope of the invention, and it should be noted that: it will be apparent to those skilled in the art that various modifications and equivalents can be made without departing from the spirit of the invention, and it is intended that all such modifications and equivalents fall within the scope of the invention as defined in the claims.

Claims (8)

1. A preparation method of a Cu nanorod structured catalyst is characterized by comprising the following steps:
step 1: mixing raw materials of pure Cu, pure Zr and pure Ni evenly, and preparing the Cu by utilizing a vacuum arc furnace and high vacuum melt-spun equipmentxZryNizAn amorphous alloy thin strip;
step 2: the obtained CuxZryNizPlacing the amorphous alloy thin strip in hydrofluoric acid solution, and placing at 40-60 ℃ for chemical dealloying;
and step 3: the obtained dealloyed CuxZryNizTaking out the amorphous alloy thin strip, repeatedly soaking and cleaning the amorphous alloy thin strip by using deionized water and alcohol in sequence, and drying to obtain a Cu nano rod-shaped catalyst;
the step 1 specifically comprises the following steps:
step 1.1: according to CuxZryNizWeighing the Cu, Zr and Ni element materials according to the target components, and uniformly mixing to obtain a smelting raw material, wherein the purity of each element material is more than 99.9%; wherein x, y and z respectively correspond to the atomic percent of each alloy element, wherein x is more than or equal to 25 and less than or equal to 45, y is more than or equal to 20 and less than or equal to 40, z is more than or equal to 30 and less than or equal to 45, and x + y + z = 100;
step 1.2: putting the smelting raw material obtained in the step 1.1 into a vacuum arc smelting furnace, smelting under the argon protective atmosphere, continuously smelting after the raw material is molten, stopping heating to enable the alloy to be cooled to be solidified along with a crucible, turning the alloy over, repeatedly smelting, and cooling to obtain a master alloy ingot with uniform components;
step 1.3: crushing the mother alloy ingot obtained in the step 1.2 into small pieces, putting the small pieces of alloy ingot into a quartz tube with an opening diameter of 1-2 mm, placing the quartz tube into an induction coil of vacuum melt-spinning equipment for fixing, adjusting the distance between the quartz tube and a copper roller, closing a cavity, and pumping the cavity to ensure that the vacuum degree of the cavity is less than or equal to 5 multiplied by 10-3Pa, filling inert gas argon as a protective atmosphere, and adjusting the pressure difference between the inside and the outside of the cavity;
step 1.4: melting alloy blocks by adopting induction melting, and spraying alloy liquid in a molten state onto a copper roller rotating at a high speed by utilizing pressure difference to obtain an amorphous alloy thin belt; the smelting temperature is 950-1150 ℃;
the concentration of the hydrofluoric acid solution is 0.8-1.2 mol/L.
2. The method for preparing a Cu nanorod structured catalyst according to claim 1, wherein the standing time at 40-60 ℃ is 5-72 hours.
3. The method for preparing a Cu nanorod structured catalyst according to claim 1, wherein the duration of the smelting after the raw materials are melted is 3-8 minutes.
4. The method of claim 1, wherein the number of times of the repeated melting is 3 to 5.
5. The method for preparing a Cu nanorod structured catalyst according to claim 1, wherein the linear speed of the copper roller rotating at a high speed is 25-30 m/s.
6. The method for preparing a Cu nanorod structured catalyst according to claim 1, wherein in the step 3, the drying is natural drying at room temperature.
7. The method for preparing a Cu nanorod structured catalyst according to claim 1, wherein the Cu nanorod structured catalyst obtained in the step 3 has a diameter of 100-160 nm and a length of 400-480 nm.
8. Use of a Cu nanorod structured catalyst prepared according to the method of claim 1 in an anode catalyst for a methanol fuel cell.
CN201810378503.0A 2018-04-25 2018-04-25 Preparation method and application of Cu nanorod-structured catalyst Active CN108767268B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201810378503.0A CN108767268B (en) 2018-04-25 2018-04-25 Preparation method and application of Cu nanorod-structured catalyst

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201810378503.0A CN108767268B (en) 2018-04-25 2018-04-25 Preparation method and application of Cu nanorod-structured catalyst

Publications (2)

Publication Number Publication Date
CN108767268A CN108767268A (en) 2018-11-06
CN108767268B true CN108767268B (en) 2021-04-06

Family

ID=64011826

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201810378503.0A Active CN108767268B (en) 2018-04-25 2018-04-25 Preparation method and application of Cu nanorod-structured catalyst

Country Status (1)

Country Link
CN (1) CN108767268B (en)

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN110433832B (en) * 2019-07-04 2022-02-22 天津大学 Self-supporting nano porous nitrogen reduction catalyst and preparation method thereof
CN113005460A (en) * 2021-03-12 2021-06-22 沈阳大学 Method for improving electrocatalytic oxidation performance of amorphous alloy
CN115178270B (en) * 2022-08-19 2023-12-19 南京工程学院 Vascular structure copper-rich bifunctional catalyst and preparation method thereof

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103343253A (en) * 2013-07-03 2013-10-09 河北工业大学 Method for preparing nano-porous copper
CN105478119A (en) * 2016-01-15 2016-04-13 东南大学 Anode catalyst material for direct alcohol fuel cell and preparation method for anode catalyst material

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2017015204A1 (en) * 2015-07-17 2017-01-26 Cornell University Copper palladium compositions as oxidation and reduction catalysts
CN107620016B (en) * 2017-07-31 2019-06-25 中国矿业大学 A kind of Ti base noncrystal alloy of the element containing Si and preparation method thereof

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103343253A (en) * 2013-07-03 2013-10-09 河北工业大学 Method for preparing nano-porous copper
CN105478119A (en) * 2016-01-15 2016-04-13 东南大学 Anode catalyst material for direct alcohol fuel cell and preparation method for anode catalyst material

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
Applying a new criterion to predict glass forming alloys in the Zr-Ni-Cu ternary system;Deo, L. P.等;《JOURNAL OF ALLOYS AND COMPOUNDS》;20121129;第553卷;摘要、第213页右栏第1段-第215页右栏第4段、图2-3、表4 *

Also Published As

Publication number Publication date
CN108767268A (en) 2018-11-06

Similar Documents

Publication Publication Date Title
CN108767268B (en) Preparation method and application of Cu nanorod-structured catalyst
CN107217219A (en) It is a kind of for Fe Co P C systems amorphous elctro-catalyst of efficient evolving hydrogen reaction and preparation method thereof
Wang et al. Novel Raney-like nanoporous Pd catalyst with superior electrocatalytic activity towards ethanol electro-oxidation
CN110146531B (en) Large-size bicontinuous porous foam bismuth and preparation method thereof
CN108767277B (en) Fe-Pd-based nano-porous material and preparation method thereof
CN104831197B (en) A kind of preparation method of nano porous copper silver
CN108914156B (en) Fe-Co-Mo-P-C amorphous alloy electrocatalyst and preparation method and application thereof
CN112090436B (en) Nickel-based catalyst, preparation method and application
CN110923746A (en) Nano-porous Fe-P-C material, preparation method thereof and application thereof in hydrogen production by water electrolysis
CN109023412A (en) A kind of nanoporous ambrose alloy/amorphous combination electrode material and preparation method thereof
CN112144028B (en) Method for preparing bismuth oxide nanowire film by inverted heating
CN109055973A (en) Aluminium adulterates three-D nano-porous metal sulfide hydrogen-precipitating electrode method of preparation and use
CN111841543A (en) Preparation method and application of spinel type oxide catalyst
CN109207958B (en) A kind of preparation method of the phosphating sludge nano-chip arrays structure perpendicular to substrate grown
CN110952110A (en) Nano-porous Pd-Fe-P-C material, preparation method thereof and application thereof in hydrogen production by water electrolysis
CN111041519A (en) Non-noble metal amorphous electrolyzed water anode material and in-situ growth preparation method
CN107579257B (en) Transition metal core-shell structure film electrocatalyst and preparation method thereof
CN112624176B (en) CuO nano-sheet rich in oxygen vacancies and preparation method and application thereof
CN111455292A (en) Amorphous alloy material, preparation method and application thereof
CN110357160B (en) Network amorphous molybdenum oxide nano material and preparation method and application thereof
CN104867681B (en) Nano-porous copper silver supported manganese dioxide electrode slice and preparation method therefor
CN110791771A (en) Integrated transition metal oxygen evolution catalytic material and preparation method thereof
CN105478119A (en) Anode catalyst material for direct alcohol fuel cell and preparation method for anode catalyst material
CN110923737A (en) Nano porous hydrogen production catalyst and preparation method thereof
CN111545221B (en) Homologous metal gradient material and preparation method and application thereof

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
GR01 Patent grant
GR01 Patent grant