Structure for accurately measuring precious metal loading capacity of proton exchange membrane
By designing inner, middle, and outer tubular structures, combined with rare earth compaction sheets and Mylar membrane supports, the problem of accurately detecting the precious metal loading in proton exchange membrane fuel cells was solved, achieving both stability and non-destructive testing.
Patent Information
- Application Number
- CN202422632888.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-10-30
- Publication Date
- 2025-11-04
- Estimated Expiration
- 2034-10-30
AI Technical Summary
Existing technologies struggle to accurately detect the loading of precious metals in proton exchange membrane fuel cells, especially when the MEA film is very thin. XRF analysis suffers from penetration effects and sample instability, leading to measurement errors.
A structure comprising an inner, middle, and outer tube is designed, supported by rare earth compacted sheets and Mylar membranes. An interference fit is used to ensure sample stability, and the strong absorption capacity of rare earth elements is utilized to increase the sample thickness to accommodate XRF detection.
It improves the accuracy and stability of detection, simplifies the sample preparation process, is suitable for rapid detection in laboratories and production lines, reduces measurement errors, and achieves non-destructive testing.
Smart Images
Figure CN223513976U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of precious metal analysis technology, and in particular to a structure for accurately measuring the precious metal loading of a proton exchange membrane. Background Technology
[0002] Proton exchange membrane fuel cells (PEMFCs), as the core structure of hydrogen fuel cell technology for new energy vehicles, are well-suited for this field due to their simple structure, rapid start-up, and high energy density. The catalysts used in PEMFCs are typically platinum (Pt) catalysts, with Pt / C type catalysts considered to have the best performance. In recent years, ruthenium (Ru), copper (Cu), nickel (Ni), and cobalt (Co) have been added to the catalysts, while iridium (Ir) has also been shown to have better performance as a negative electrode material.
[0003] For the detection of precious metal content in traditional catalysts, gravimetric methods or ICP are usually used. The former is complicated and time-consuming, while the latter can perform quantitative analysis of multiple elements at the same time. However, for Pt / C catalysts, the high carbon content requires complicated pretreatment steps. For Ru, ruthenium trichloride is easily volatilized in acidic environments. For Ir, it is difficult to completely dissolve precious metals by acid dissolution or alkali melting. XRF (X-ray fluorescence spectrometry) analysis technology has become a potential detection tool due to its rapid and non-destructive characteristics.
[0004] Due to the high Pt content and complex support structure of PEMFC catalysts, they are difficult to directly apply to XRF analysis. Therefore, it is necessary to design a dedicated sample structure suitable for XRF analysis while ensuring the stability of the sample structure and preventing it from becoming loose or damaged. In addition, because the MEA membrane electrode of PEM is too thin, it is very easy to penetrate when directly used for XRF detection, thus affecting the test results. The best way to deal with the penetration effect is to increase the thickness. Moreover, the heavier the element, the easier it is to achieve the infinite thickness required for XRF detection. This invention uses a quantitative and structurally very stable alumina-cerium zirconium powder mixture, which utilizes the strong absorption of X-rays by rare earth elements to achieve the infinite thickness required for sample detection. Summary of the Invention
[0005] To address the shortcomings of existing technologies, this invention provides a structure for accurately measuring the noble metal loading of proton exchange membranes. This method is specifically designed to solve the problem of detecting the content of noble metals (such as Pt, Ru, Ir, etc.) in PEM catalysts, especially when the MEA film thickness is very thin, ensuring the accuracy and stability of the detection.
[0006] The technical solution adopted in this utility model is:
[0007] A structure for accurately measuring the noble metal loading of a proton exchange membrane, comprising an inner tube, a middle tube, and an outer tube arranged sequentially from the inside to the outside. Each of the inner, middle, and outer tubes is a hollow cylinder. A first supporting membrane is disposed at the bottom of the inner tube, and a second supporting membrane is disposed at the bottom of the middle tube. The inner, middle, and outer tubes are interference-fitted. A rare earth compaction sheet and a proton exchange membrane are sequentially disposed between the first and second supporting membranes. The rare earth compaction sheet is disposed on the side closer to the first supporting membrane, and the proton exchange membrane to be measured is disposed on the side closer to the second supporting membrane.
[0008] The first support membrane of the inner tube is used to support the sample, and a small hole is provided on the first support membrane for venting; the diameter of the rare earth compaction sheet is smaller than the inner diameter of the inner tube so that it can be properly compressed during installation to ensure the tightness of contact between the rare earth compaction sheet and the structure of this utility model.
[0009] The interference fit between the inner, middle, and outer tubes ensures that the sample will not shift or loosen during testing. The interference fit ensures that each layer fits tightly, thus providing a stable support platform during testing, preventing sample movement and avoiding measurement errors caused by sample instability.
[0010] Preferably, in the structure for accurately measuring the noble metal loading of the proton exchange membrane, the first and second supporting membranes are both Mylar membranes with a thickness of 4.0-10.0 μm.
[0011] Preferably, in the structure for accurately measuring the noble metal loading of the proton exchange membrane, the inner diameter of the inner tube is larger than the diameter of the rare earth compacted sheet.
[0012] Preferably, in the structure for accurately measuring the noble metal loading of the proton exchange membrane, an vent hole is provided on the first support membrane, and the vent hole has a diameter of 2-4 mm.
[0013] Preferably, in the structure for accurately measuring the noble metal loading of the proton exchange membrane, the inner tube has an inner diameter of 3.5-8.0 mm and a thickness of 0.1-0.2 mm; the middle tube has an inner diameter of 3.7-8.2 mm and a thickness of 0.1-0.2 mm; and the outer tube has an inner diameter of 3.9-8.4 mm and a thickness of 0.1-0.2 mm.
[0014] Preferably, in the structure for accurately measuring the noble metal loading of the proton exchange membrane, the rare earth compaction sheet is made of cerium-zirconium powder.
[0015] Preferably, in the structure for accurately measuring the noble metal loading of the proton exchange membrane, the first support membrane and the second support membrane are both circular in shape, the diameter of the first support membrane is larger than the diameter of the inner tube, and the first support membrane is fixed by the interference fit between the inner tube and the middle tube.
[0016] Preferably, in the structure for accurately measuring the noble metal loading of the proton exchange membrane, the diameter of the second support membrane is larger than the diameter of the middle tube, and the second support membrane is fixed by an interference fit between the middle tube and the outer tube. The first support membrane of the inner tube is used to support the sample, and a small hole is provided on the first support membrane for venting; the diameter of the rare earth compaction sheet is smaller than the inner diameter of the inner tube, so that it can be appropriately compressed during installation to ensure the tight contact between the rare earth compaction sheet and the structure of this invention.
[0017] The interference fit between the inner, middle, and outer tubes ensures that the sample will not shift or loosen during testing. The interference fit ensures that each layer fits tightly, thus providing a stable support platform during testing, preventing sample movement and avoiding measurement errors caused by sample instability.
[0018] The beneficial effects of the technical solution provided by this utility model embodiment are:
[0019] (1) The structure for accurately measuring the precious metal loading of proton exchange membranes of this utility model includes an inner tube, a middle tube and an outer tube arranged sequentially from the inside to the outside. A first support membrane is arranged at the bottom of the inner tube and a second support membrane is arranged at the bottom of the middle tube. A rare earth compaction sheet and the proton exchange membrane to be tested are arranged sequentially between the first support membrane and the second support membrane. The unique three-layer structure design and the use of rare earth compaction sheet not only improve the stability of the sample during the detection process, but also simplify the sample preparation process. This structure has high accuracy and reliability and is suitable for research and production environments of various proton exchange membrane fuel cells.
[0020] (2) The structure of this utility model for accurately measuring the precious metal loading of proton exchange membrane has an exhaust hole on the first support membrane, which can effectively discharge the air generated during the assembly process, ensuring the accuracy of the test results. The exhaust hole avoids the error caused by the presence of air in the sample during the test process, ensuring the authenticity and reliability of the measurement data.
[0021] (3) The structure of this utility model for accurately measuring the noble metal loading of proton exchange membrane has an interference fit between the inner tube, the middle tube and the outer tube, which makes the structure stable and ensures that the sample will not be displaced or loosened during the test. The interference fit makes each layer fit tightly together, thus providing a stable support platform during the test, preventing the sample from moving and avoiding measurement errors caused by sample instability.
[0022] (4) The structure of this utility model for accurately measuring the precious metal loading of proton exchange membrane is simple in structure, easy to assemble, and suitable for use in laboratories and production lines. This structure is not only easy for operators to quickly assemble and disassemble in laboratory environments, but also suitable for rapid detection of large batches of samples on production lines. Through simple structural design, it realizes complex functions while leaving room for possible future improvements, and has great market potential and development space.
[0023] (5) The structure of this utility model for accurately measuring the noble metal loading of proton exchange membranes, the first support membrane and the second support membrane are both Mylar membranes. Mylar membranes have good chemical stability and mechanical strength and are suitable for various testing environments. These materials not only have good chemical stability and can maintain performance in different testing environments, but also have sufficient mechanical strength to ensure that they are not easily damaged during assembly and testing.
[0024] (6) The structure of this utility model for accurately measuring the noble metal loading of proton exchange membrane solves the important problem of X-ray penetration of MEA membrane. Because the membrane electrode of proton exchange membrane is too thin, it is easy to penetrate directly by XRF detection, which affects the test results. The quantitative and structurally stable cerium zirconium powder is used to make the sample reach the infinite thickness required for detection by utilizing the strong absorption capacity of rare earth elements for X-rays, which effectively solves the penetration effect problem. The use of rare earth compaction sheet increases the thickness of the sample through cerium zirconium powder, making the sample reach the infinite thickness required for XRF, thereby solving the penetration problem of thin film sample in XRF detection.
[0025] (7) The structure of this utility model for accurately measuring the precious metal loading of the proton exchange membrane is a detachable structure that allows for complete recycling of the proton exchange membrane, thus enabling the XRF equipment to perform non-destructive testing. The design also simplifies the sample preparation process, making the entire testing process more economical and efficient. Attached Figure Description
[0026] Figure 1 This is a schematic diagram of the structure of the present invention for accurately measuring the noble metal loading of a proton exchange membrane.
[0027] Figure 2 This is a cross-sectional view of the structure of the present invention for accurately measuring the noble metal loading of a proton exchange membrane. Detailed Implementation
[0028] In the description of this utility model, it should be understood that the orientation or positional relationship indicated by directional terms such as "inner" and "outer", "upper" and "lower", "front" and "back" is usually based on the orientation or positional relationship shown in the accompanying drawings. It is only for the convenience of describing this utility model and simplifying the description. Unless otherwise stated, these directional terms do not indicate or imply that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting the scope of protection of this utility model.
[0029] To make the objectives, technical solutions, and advantages of this utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain this utility model and are not intended to limit this utility model.
[0030] like Figure 1-2 A structure for accurately measuring the noble metal loading of a proton exchange membrane includes an inner tube 1, a middle tube 2, and an outer tube 3 arranged sequentially from the inside to the outside. The inner tube 1, middle tube 2, and outer tube 3 are all hollow cylinders. A first support membrane 4 is provided at the bottom of the inner tube 1, and a second support membrane 5 is provided at the bottom of the middle tube 2. The inner tube 1, middle tube 2, and outer tube 3 are interference-fitted. A rare earth compaction sheet 6 and a proton exchange membrane 7 are arranged sequentially between the first support membrane 4 and the second support membrane 5. The rare earth compaction sheet 6 is located on the side closer to the first support membrane 4, and the proton exchange membrane 7 to be measured is located on the side closer to the second support membrane 5.
[0031] The first support membrane 4 and the second support membrane 5 are both Mylar membranes with a thickness of 4.0-10.0 μm; the inner diameter of the inner tube 1 is larger than the diameter of the rare earth compaction sheet 6; the first support membrane 4 is provided with vent holes for venting, and the vent hole diameter is 2-4 mm; the inner diameter of the inner tube 1 is 3.5-8.0 mm and the thickness is 0.1-0.2 mm; the inner diameter of the middle tube 2 is 3.7-8.2 mm and the thickness is 0.1-0.2 mm; the inner diameter of the outer tube 3 is 3.9-8.4 mm and the thickness is 0.1-0.2 mm; the rare earth compaction sheet 6 is made of cerium-zirconium powder.
[0032] The first support membrane 4 and the second support membrane 5 are both circular in shape. The diameter of the first support membrane 4 is larger than the diameter of the inner tube 1. The first support membrane 4 is fixed by the interference fit between the inner tube 1 and the middle tube 2. The diameter of the second support membrane 5 is larger than the diameter of the middle tube 2. The second support membrane 5 is fixed by the interference fit between the middle tube 2 and the outer tube 3. The rare earth compacted tablet is made of cerium zirconium powder, which is obtained by pressing the cerium zirconium powder into shape in a tablet press after high-temperature calcination.
[0033] The assembly steps of this utility model are as follows:
[0034] Step S1. Place a Mylar membrane with a diameter of 7 mm and a thickness of 6 micrometers at the bottom of the middle tube 2 as the second support membrane 5, and press the middle tube 2 into the outer tube 3 so that the middle tube 2 and the outer tube 3 are tightly bonded.
[0035] Step S2. Place the proton exchange membrane 7 to be tested on the Mylar membrane at the bottom of the middle tube 2. The size of the proton exchange membrane 7 to be tested is consistent with the area of the rare earth compaction sheet 6. The diameter of the rare earth compaction sheet 6 is smaller than the diameter of the inner tube 1. Place the rare earth compaction sheet 6 on the proton exchange membrane 7 to be tested. Then place a Mylar membrane with a diameter of 5.0 mm and a thickness of 6 micrometers at the bottom of the inner layer as the first support membrane 4, and ensure that there is a small hole on the first support membrane for venting. The diameter of the vent hole is 2 mm.
[0036] Step S3. Press the inner tube 1 into the middle tube 2 to make the inner tube 1 and the middle tube 2 tightly connected and assembled into the structure to be tested.
[0037] Step S4. After the sample test is completed, the proton exchange membrane to be tested can be recovered by destroying the first support membrane 4 and the second support membrane 5. During the test, the proton exchange membrane 7 to be tested is in an undamaged state. When using the structure prepared by this invention for XRF detection, the structure is placed in the center of the sample box.
[0038] Finally, it should be noted that the above specific embodiments are only used to illustrate the technical solution of this utility model and not to limit it. Although this utility model has been described in detail with reference to examples, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solution of this utility model without departing from the spirit and scope of the technical solution of this utility model, and all such modifications and substitutions should be covered within the scope of the claims of this utility model.
Claims
1. A structure for accurately measuring the noble metal loading of a proton exchange membrane, characterized in that: The device includes an inner tube (1), a middle tube (2), and an outer tube (3) arranged sequentially from the inside to the outside. The inner tube (1), the middle tube (2), and the outer tube (3) are all hollow cylinders. A first support membrane (4) is provided at the bottom of the inner tube (1), and a second support membrane (5) is provided at the bottom of the middle tube (2). The inner tube (1), the middle tube (2), and the outer tube (3) are interference-fitted. A rare earth compaction sheet (6) and a proton exchange membrane (7) to be tested are arranged sequentially between the first support membrane (4) and the second support membrane (5). The rare earth compaction sheet (6) is located on the side closer to the first support membrane (4), and the proton exchange membrane (7) to be tested is located on the side closer to the second support membrane (5).
2. The structure for accurately measuring the noble metal loading of a proton exchange membrane according to claim 1, characterized in that: The first support membrane (4) and the second support membrane (5) are both Mylar membranes with a thickness of 4.0-10.0 μm.
3. The structure for accurately measuring the noble metal loading of a proton exchange membrane according to claim 1, characterized in that: The inner diameter of the inner tube (1) is larger than the diameter of the rare earth compacted sheet (6).
4. The structure for accurately measuring the noble metal loading of a proton exchange membrane according to claim 1, characterized in that: The first support membrane (4) is provided with an exhaust hole, the diameter of which is 2-4 mm.
5. The structure for accurately measuring the noble metal loading of a proton exchange membrane according to claim 1, characterized in that: The inner tube (1) has an inner diameter of 3.5-8.0 mm and a thickness of 0.1-0.2 mm; the middle tube (2) has an inner diameter of 3.7-8.2 mm and a thickness of 0.1-0.2 mm; and the outer tube (3) has an inner diameter of 3.9-8.4 mm and a thickness of 0.1-0.2 mm.
6. The structure for accurately measuring the noble metal loading of a proton exchange membrane according to claim 1, characterized in that: The rare earth compacted sheet (6) is made of cerium zirconium powder.
7. The structure for accurately measuring the noble metal loading of a proton exchange membrane according to claim 1, characterized in that: The first support membrane (4) and the second support membrane (5) are both circular in shape. The diameter of the first support membrane (4) is larger than the diameter of the inner tube (1). The first support membrane (4) is fixed by the interference fit between the inner tube (1) and the middle tube (2).
8. The structure for accurately measuring the noble metal loading of a proton exchange membrane according to claim 7, characterized in that: The diameter of the second support membrane (5) is larger than the diameter of the middle tube (2), and the second support membrane (5) is fixed by the interference fit between the middle tube (2) and the outer tube (3).