CN112903762A - Carbon monoxide gas sensor based on graphene aerosol material - Google Patents
Carbon monoxide gas sensor based on graphene aerosol material Download PDFInfo
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- CN112903762A CN112903762A CN202110181375.2A CN202110181375A CN112903762A CN 112903762 A CN112903762 A CN 112903762A CN 202110181375 A CN202110181375 A CN 202110181375A CN 112903762 A CN112903762 A CN 112903762A
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- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 title claims abstract description 34
- 229910021389 graphene Inorganic materials 0.000 title claims abstract description 34
- 239000000463 material Substances 0.000 title claims abstract description 32
- UGFAIRIUMAVXCW-UHFFFAOYSA-N Carbon monoxide Chemical compound [O+]#[C-] UGFAIRIUMAVXCW-UHFFFAOYSA-N 0.000 title claims abstract description 29
- 229910002091 carbon monoxide Inorganic materials 0.000 title claims abstract description 29
- 239000000443 aerosol Substances 0.000 title claims abstract description 21
- XOLBLPGZBRYERU-UHFFFAOYSA-N tin dioxide Chemical compound O=[Sn]=O XOLBLPGZBRYERU-UHFFFAOYSA-N 0.000 claims abstract description 61
- 238000000034 method Methods 0.000 claims abstract description 19
- 239000011248 coating agent Substances 0.000 claims abstract description 9
- 238000000576 coating method Methods 0.000 claims abstract description 9
- 238000007639 printing Methods 0.000 claims abstract description 8
- 239000011540 sensing material Substances 0.000 claims description 24
- 239000002086 nanomaterial Substances 0.000 claims description 8
- 238000003786 synthesis reaction Methods 0.000 claims description 4
- 238000001027 hydrothermal synthesis Methods 0.000 claims description 3
- 239000002245 particle Substances 0.000 claims description 3
- 238000004108 freeze drying Methods 0.000 claims description 2
- 238000004519 manufacturing process Methods 0.000 claims description 2
- 238000002360 preparation method Methods 0.000 claims description 2
- 239000004065 semiconductor Substances 0.000 abstract description 15
- 239000002105 nanoparticle Substances 0.000 abstract description 11
- 238000012544 monitoring process Methods 0.000 abstract description 5
- 238000005265 energy consumption Methods 0.000 abstract description 4
- 230000035945 sensitivity Effects 0.000 abstract description 4
- 239000002360 explosive Substances 0.000 abstract description 3
- 238000011084 recovery Methods 0.000 abstract description 3
- 238000005452 bending Methods 0.000 abstract description 2
- 238000005516 engineering process Methods 0.000 abstract description 2
- 238000011031 large-scale manufacturing process Methods 0.000 abstract description 2
- 239000007789 gas Substances 0.000 description 40
- 239000010410 layer Substances 0.000 description 5
- 230000000694 effects Effects 0.000 description 3
- 239000002344 surface layer Substances 0.000 description 3
- 102000001554 Hemoglobins Human genes 0.000 description 2
- 108010054147 Hemoglobins Proteins 0.000 description 2
- 239000004642 Polyimide Substances 0.000 description 2
- BQCADISMDOOEFD-UHFFFAOYSA-N Silver Chemical compound [Ag] BQCADISMDOOEFD-UHFFFAOYSA-N 0.000 description 2
- 230000007547 defect Effects 0.000 description 2
- 238000003795 desorption Methods 0.000 description 2
- 238000001514 detection method Methods 0.000 description 2
- 229920001721 polyimide Polymers 0.000 description 2
- 229910052709 silver Inorganic materials 0.000 description 2
- 239000004332 silver Substances 0.000 description 2
- 238000001179 sorption measurement Methods 0.000 description 2
- 239000000758 substrate Substances 0.000 description 2
- 206010021143 Hypoxia Diseases 0.000 description 1
- 206010070863 Toxicity to various agents Diseases 0.000 description 1
- 230000001133 acceleration Effects 0.000 description 1
- 238000004458 analytical method Methods 0.000 description 1
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- 239000008280 blood Substances 0.000 description 1
- 210000004369 blood Anatomy 0.000 description 1
- 229910052799 carbon Inorganic materials 0.000 description 1
- 239000003245 coal Substances 0.000 description 1
- 238000002485 combustion reaction Methods 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 238000004880 explosion Methods 0.000 description 1
- 239000000383 hazardous chemical Substances 0.000 description 1
- 230000007954 hypoxia Effects 0.000 description 1
- 238000009776 industrial production Methods 0.000 description 1
- 238000005065 mining Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 210000000653 nervous system Anatomy 0.000 description 1
- 231100000344 non-irritating Toxicity 0.000 description 1
- 230000009965 odorless effect Effects 0.000 description 1
- 229910052760 oxygen Inorganic materials 0.000 description 1
- 239000001301 oxygen Substances 0.000 description 1
- 239000011527 polyurethane coating Substances 0.000 description 1
- 238000002336 sorption--desorption measurement Methods 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N27/00—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means
- G01N27/02—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating impedance
- G01N27/04—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating impedance by investigating resistance
- G01N27/12—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating impedance by investigating resistance of a solid body in dependence upon absorption of a fluid; of a solid body in dependence upon reaction with a fluid, for detecting components in the fluid
- G01N27/125—Composition of the body, e.g. the composition of its sensitive layer
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- Chemical Kinetics & Catalysis (AREA)
- Electrochemistry (AREA)
- Physics & Mathematics (AREA)
- Health & Medical Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Analytical Chemistry (AREA)
- Biochemistry (AREA)
- General Health & Medical Sciences (AREA)
- General Physics & Mathematics (AREA)
- Immunology (AREA)
- Pathology (AREA)
- Investigating Or Analyzing Materials By The Use Of Fluid Adsorption Or Reactions (AREA)
Abstract
The invention discloses a carbon monoxide gas sensor based on a graphene aerosol material, which relates to the technical field of semiconductor gas sensors and comprises the following components: 1) combining graphene with tin dioxide nanoparticles; 2) forming a three-dimensional graphene aerosol; 3) and (3) an electronic printing process. According to the invention, the graphene is applied, so that the sensor can work at room temperature, the thermal stability of the material is improved, the energy consumption of the device is reduced, and the generation of inflammable and explosive gas in a high-temperature ignition monitoring environment is avoided; meanwhile, the thickness of the sensing coating is reduced to the minimum by utilizing the technology of the printed electronic device, so that the sensitivity and the response/recovery time of the sensor are effectively improved; the material cost and the physical volume of the device are reduced, the reliability of the device under physical impact (bending, stretching and the like) is improved, and meanwhile, low-cost large-scale production can be effectively carried out.
Description
Technical Field
The invention relates to the field of semiconductor gas sensors, in particular to a carbon monoxide gas sensor based on a graphene aerosol material.
Background
Carbon monoxide is a colorless, odorless and nonirritating gas, generally generated by incomplete combustion of carbon-containing substances or generated in leakage of liquefied gas pipelines, industrial production gas and coal mining, is also a combustible and explosive dangerous gas, has a mixed explosion limit of 12% -75% with air, is combined with hemoglobin in blood, has an affinity which is more than 200 times higher than that of oxygen and hemoglobin, and can cause hypoxia and toxic symptoms when too much carbon monoxide is absorbed in a short time, and can cause serious damage or even death of a nervous system when the carbon monoxide is seriously damaged. Therefore, the detection and monitoring of the concentration of the carbon monoxide gas are required in the fields of daily air quality detection, hazardous chemical transport gas monitoring and industrial environmental safety monitoring.
The traditional semiconductor type gas sensing mainly comes from the electron exchange between adsorbed gas and sensing material, when carbon monoxide gas contacts with tin dioxide nano particles, an electron is given, and the electron can cause the energy band of the tin dioxide semiconductor material to change, so that the resistance value of the tin dioxide semiconductor material changes. The method improves the overall porosity of the tin dioxide material and provides a better channel for the adsorption and desorption of carbon monoxide gas. However, the gas sensor in the prior art has the disadvantages of low sensing performance, low signal strength (low sensitivity) and slow signal response/recovery speed; the energy consumption is high, and the sensing is carried out at the temperature of 200 ℃ and 400 ℃; the service life of the material is short, and the service life of the sensing material is obviously reduced under the high-temperature working condition.
Therefore, those skilled in the art have made efforts to develop a carbon monoxide gas sensor based on a graphene aerosol material, which can improve sensing performance, reduce power consumption, and increase the lifetime of the sensing material.
Disclosure of Invention
In view of the above-mentioned drawbacks of the prior art, the technical problems to be solved by the present invention are: the defects of high energy consumption and short service life caused by low sensitivity of the gas sensor and the need of working under a high-temperature condition are overcome.
In order to achieve the above object, the present invention provides a graphene aerosol material-based carbon monoxide gas sensor preparation process, including: 1) combining graphene with a tin dioxide nanomaterial; 2) forming a three-dimensional graphene aerosol; 3) and (3) an electronic printing process.
Further, the step 1) comprises: graphene and tin dioxide nanomaterials were combined by using inorganic chemical synthesis means.
Further, the graphene is a two-dimensional material.
Further, the tin dioxide nano material is synthesized by a high-temperature high-pressure hydrothermal method.
Further, the step 2) comprises: and (2) carrying out freeze drying on the product obtained in the step 1) to obtain the three-dimensional structure TrGO aerosol.
Furthermore, the density of the three-dimensional structure TrGO aerosol is low, and the porosity is large.
Further, the step 3) comprises: and printing the three-dimensional structure TrGO aerosol on the sensor by adopting a printing electronic process to form a sensing material coating.
Further, the sensing material coating is 500 nanometers.
Further, a pn junction is formed between the particles of the tin dioxide nanoparticles and the graphene material.
Further, the present invention provides a graphene aerosol material-based carbon monoxide gas sensor, which is manufactured by the manufacturing process.
Compared with the prior art, the invention at least has the following beneficial technical effects:
1. the performance that the sensor can work at room temperature is realized by applying the graphene. The defect that the working temperature of the traditional carbon monoxide gas sensor is about 200 ℃ is overcome. The thermal stability of the material is improved, the energy consumption of the device is reduced, and the generation of inflammable and explosive gas in a high-temperature ignition monitoring environment is avoided.
2. The invention utilizes the technology of printed electronic devices, the thickness of the sensing coating is reduced to the minimum, and the sensitivity and the response/recovery time of the sensor are effectively improved; the material cost and the physical volume of the device are reduced, the reliability of the device under physical impact (bending, stretching and the like) is improved, and meanwhile, low-cost large-scale production can be effectively carried out.
The conception, the specific structure and the technical effects of the present invention will be further described with reference to the accompanying drawings to fully understand the objects, the features and the effects of the present invention.
Drawings
FIG. 1 is a TrGO sensing material sensing principle of the carbon monoxide gas sensor of the present invention;
FIG. 2 is a schematic illustration of a TrGO sensor material of the carbon monoxide gas sensor of the present invention;
FIG. 3 is a schematic view of the pn junction principle of the carbon monoxide gas sensor of the present invention;
fig. 4 is a schematic structural view of a carbon monoxide gas sensor of the present invention;
wherein: 1-SnO2A nanoparticle; 2-graphene; 3-CO; 4-a bottom layer polyimide flexible substrate; 5-surface layer TrGO sensing material layer; 6-high precision silver electrode.
Detailed Description
The preferred embodiments of the present invention will be described below with reference to the accompanying drawings for clarity and understanding of technical contents. The present invention may be embodied in many different forms of embodiments and the scope of the invention is not limited to the embodiments set forth herein.
In the drawings, structurally identical elements are represented by like reference numerals, and structurally or functionally similar elements are represented by like reference numerals throughout the several views. The size and thickness of each component shown in the drawings are arbitrarily illustrated, and the present invention is not limited to the size and thickness of each component. The thickness of the components may be exaggerated where appropriate in the figures to improve clarity.
As shown in fig. 4, an embodiment of the present invention provides a carbon monoxide gas sensor based on a graphene aerosol material, which includes a bottom polyimide flexible substrate 4, a surface polyurethane coating, a high-precision silver electrode 6, and a surface TrGO sensing material layer 5, where the sensing performance of the surface TrGO sensing material layer 5 is improved, and the main principle is as shown in fig. 1 to 3.
The semiconductor type gas sensing mainly comes from the electron exchange between the adsorbed gas and the sensing material, when carbon monoxide gas contacts with the tin dioxide nano-particles, an electron is given, and the electron can cause the energy band of the tin dioxide semiconductor material to change, so that the resistance value of the tin dioxide semiconductor material changes. In order to create a better contact environment for carbon monoxide and tin dioxide materials, it is a common practice to synthesize tin dioxide nanoparticles by a high-temperature high-pressure hydrothermal method. The method improves the overall porosity of the tin dioxide material and provides a better channel for the adsorption and desorption of carbon monoxide gas. On the basis of tin dioxide nanoparticles, graphene two-dimensional materials are used. Graphene, another widely used semiconductor material, also undergoes electron exchange when carbon monoxide gas is adsorbed/desorbed on the surface of graphene, thereby causing a change in resistance value. By using an inorganic chemical synthesis means, the graphene and the tin dioxide nano material are combined, and the response strength of the sensing material to carbon monoxide gas is further improved.
After the product obtained by the inorganic chemical synthesis process is frozen and dried, the three-dimensional structure TrGO aerosol can be obtained. The density of the three-dimensional TrGO aerosol is extremely low, the porosity is high, and the adsorption/desorption process of carbon monoxide gas and the TrGO sensing material is further facilitated.
In the semiconductor resistance type gas sensor, the thinner the sensing material is, the stronger the gas response signal is, and the faster the response speed is. The thickness of the sensing material coating of the traditional semiconductor resistance type gas sensor is between 5 and 10 microns. Through a printing electronic process, the coating of the sensing material reaches 500 nanometers, and the coating thickness of the sensing material is reduced to the maximum extent on the premise that the contact among sensing material particles is good, so that the highest gas response signal and the fastest response speed are obtained.
In conventional tin dioxide nano-sensing materials, the flow of electrons between tin dioxide nano-particles is often hindered due to the semiconductor properties of tin dioxide, so in order to achieve the sensing process, the material needs to be heated to an optimum temperature of 200-. The sensing principle of the TrGO sensing material of the embodiment is shown in fig. 3, the semiconductor type gas sensing mainly comes from the electron exchange between the adsorbed gas and the sensing material, when the carbon monoxide gas contacts with the tin dioxide nanoparticles, an electron is given, and the electron can cause the energy band of the tin dioxide semiconductor material to change, so that the resistance value of the tin dioxide semiconductor material changes. After the tin dioxide nanoparticles are decorated on the surface of graphene and form a TrGO sensing material, electrons obtained by the tin dioxide from carbon monoxide gas are further conducted to a graphene two-dimensional layer, and at the moment, a pn junction is formed between the tin dioxide nanoparticles and the graphene material, so that an electron transmission path is optimized. Meanwhile, the electron flow speed on the two-dimensional surface layer of the graphene is extremely high, and the circulation is completely barrier-free. Electrons can smoothly flow to the other end of the electrode from one end of the electrode through the two-dimensional graphene surface layer without any thermodynamic process acceleration. So that the sensing material realizes room temperature sensing.
The foregoing detailed description of the preferred embodiments of the invention has been presented. It should be understood that numerous modifications and variations could be devised by those skilled in the art in light of the present teachings without departing from the inventive concepts. Therefore, the technical solutions available to those skilled in the art through logic analysis, reasoning and limited experiments based on the prior art according to the concept of the present invention should be within the scope of protection defined by the claims.
Claims (10)
1. A preparation process of a carbon monoxide gas sensor based on a graphene aerosol material is characterized by comprising the following steps: 1) combining graphene with a tin dioxide nanomaterial; 2) forming a three-dimensional graphene aerosol; 3) and (3) an electronic printing process.
2. The process of claim 1, wherein step 1) comprises: graphene and tin dioxide nanomaterials were combined by using inorganic chemical synthesis means.
3. The process of claim 2, wherein the graphene is a two-dimensional material.
4. The process of claim 2, wherein the tin dioxide nanomaterial is synthesized by a high temperature high pressure hydrothermal method.
5. The process of claim 2, wherein step 2) comprises: and (2) carrying out freeze drying on the product obtained in the step 1) to obtain the three-dimensional structure TrGO aerosol.
6. The process of claim 5, wherein the three-dimensional TrGO aerosol has a low density and a high porosity.
7. The process of claim 5, wherein step 3) comprises: and printing the three-dimensional structure TrGO aerosol on the sensor by adopting a printing electronic process to form a sensing material coating.
8. The process of claim 7, wherein the sensing material coating thickness is 500 nm.
9. The process of claim 7, wherein particles of the tin dioxide nanomaterial form a pn junction with the graphene.
10. A graphene aerosol material based carbon monoxide gas sensor, characterized in that the sensor is made by the manufacturing process of claims 1-9.
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Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN102636522A (en) * | 2012-03-29 | 2012-08-15 | 浙江大学 | Graphene/ stannic oxide nanometer compounding resistance type film gas sensor and manufacturing method thereof |
CN103904313A (en) * | 2014-04-15 | 2014-07-02 | 山东省科学院能源研究所 | Preparation method and application of tin oxide-aza graphene aerosol composite material |
CN108120747A (en) * | 2017-11-30 | 2018-06-05 | 苏州慧闻纳米科技有限公司 | The preparation method of tin dioxide gas sensor and CO gas sensor system |
US10116000B1 (en) * | 2015-10-20 | 2018-10-30 | New Jersey Institute Of Technology | Fabrication of flexible conductive items and batteries using modified inks |
CN110554072A (en) * | 2019-08-30 | 2019-12-10 | 郑州大学 | Preparation method and application of composite material and gas sensor |
-
2021
- 2021-02-09 CN CN202110181375.2A patent/CN112903762A/en active Pending
Patent Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN102636522A (en) * | 2012-03-29 | 2012-08-15 | 浙江大学 | Graphene/ stannic oxide nanometer compounding resistance type film gas sensor and manufacturing method thereof |
CN103904313A (en) * | 2014-04-15 | 2014-07-02 | 山东省科学院能源研究所 | Preparation method and application of tin oxide-aza graphene aerosol composite material |
US10116000B1 (en) * | 2015-10-20 | 2018-10-30 | New Jersey Institute Of Technology | Fabrication of flexible conductive items and batteries using modified inks |
CN108120747A (en) * | 2017-11-30 | 2018-06-05 | 苏州慧闻纳米科技有限公司 | The preparation method of tin dioxide gas sensor and CO gas sensor system |
CN110554072A (en) * | 2019-08-30 | 2019-12-10 | 郑州大学 | Preparation method and application of composite material and gas sensor |
Non-Patent Citations (2)
Title |
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LEI LI等: "Three-Dimensional Mesoporous Graphene Aerogel-Supported SnO2 Nanocrystals for High-Performance NO2 Gas Sensing at Low Temperature", 《ANALYTICAL CHEMISTRY》 * |
唐婕 等著: "《环保陶瓷生产与应用》", 31 January 2018 * |
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