Composite porous metal plate and preparation method thereof

Abstract

The invention provides a composite porous metal plate and a preparation method, the composite porous metal plate comprises a porous metal plate, a hydrophilic treatment layer and a hydrophobic treatment layer, the hydrophilic treatment layer is constructed on the surface of the porous metal plate, the hydrophobic treatment layer is constructed on a local area of the surface of the hydrophilic treatment layer, and at least one hydrophobic area is formed on the surface of the hydrophobic treatment layer. The surface of the hydrophilic treatment layer is divided into at least two hydrophilic regions by at least one hydrophobic region, the area ratio of the hydrophobic region is 30%-50%, the area ratio of the at least two hydrophilic regions is 50%-70%, the contact angle of the hydrophilic regions is smaller than 90 degrees, and the contact angle of the hydrophobic region is larger than 120 degrees. The composite porous metal plate provided by the invention can realize efficient transmission of reactants and efficient transfer of reaction products, so that the electrochemical reaction is more sufficient, the reaction efficiency is higher, and a technical support is provided for cost reduction and efficiency improvement in the field of hydrogen production by electrolysis of water.

Description

Technical Field

[0001] The present invention relates to the technical field of catalytic device manufacturing, and particularly relates to a composite porous metal plate and a preparation method thereof. Background Art

[0002] All along, porous metal sintered bodies obtained by sintering metal powders such as titanium-based, nickel-based, and stainless steel have been used as filters. However, in recent years, they have also attracted much attention in applications such as substrates for electrodes of nickel-metal hydride batteries and lithium batteries, biological materials, catalyst substrates, fuel cells, and components of hydrogen production stacks. Among them, the porous transport layer is one of the key components in the water electrolysis technology. It plays roles such as conducting electricity, transporting gas and liquid, and supporting in the water electrolysis cell. However, the traditional porous transport layer is prone to "water flooding" due to excessive hydrophilicity or "gas blockage" due to insufficient hydrophobicity during the electrolysis process, affecting the gas-liquid two-phase transport efficiency. Summary of the Invention

[0003] Aiming at the problems existing in the prior art and the performance optimization requirements of the porous transport layer in the water electrolysis hydrogen production technology, the present invention proposes a composite porous metal plate and a preparation method thereof that achieve hydrophilic-hydrophobic functional zoning through surface modification, aiming to improve the gas-liquid transport efficiency and promote the large-scale application of electrolyzers by regulating the pore structure, surface chemical composition, and microscopic morphology.

[0004] To achieve the above object, the technical solution adopted by the present invention is as follows: A composite porous metal plate includes a porous metal plate, a hydrophilic treatment layer, and a hydrophobic treatment layer. The hydrophilic treatment layer is constructed on the surface of the porous metal plate, and the hydrophobic treatment layer is constructed on a partial area of the surface of the hydrophilic treatment layer. At least one hydrophobic region is formed on the surface of the hydrophobic treatment layer. The at least one hydrophobic region divides the surface of the hydrophilic treatment layer into at least two hydrophilic regions. The area ratio of the at least two hydrophilic regions is 50% - 70%, and the area ratio of the at least one hydrophobic region is 30% - 50%. The contact angle of the hydrophilic region is less than 90°, and the contact angle of the hydrophobic region is greater than 120°.

[0005] In some embodiments, the hydrophobic treatment layer is an amorphous structure coating, and the thickness of the amorphous structure coating is 10nm - 200nm.

[0006] In some embodiments, the substrate of the amorphous structure coating is palladium-based, platinum-based, titanium-based, or zirconium-based, and the added elements of the amorphous structure coating are palladium, platinum, titanium, zirconium, tantalum, nickel, iron, carbon, nitrogen, or phosphorus.

[0007] In some embodiments, the material of the porous metal plate is titanium, nickel, titanium alloy, nickel alloy, or stainless steel.

[0008] In some of these embodiments, the titanium alloy is Ti-6Al-4V, Ti-5Al-2.5Sn, Ti-6Al-7Nb, Ti-3Al-2.5V, Ti-2Al-2.5Zr, Ti-8Mn, Ti-6Al-6V-2Sn, Ti-6Al-2Sn-4Zr-6Mo, Ti-6Al-2Sn-4Zr-2Mo, Ti-6Al-2Sn-2Zr-2Mo, Ti-3Al-5Mo-4.5V, Ti-6Al-2Sn-4Zr-2Mo, Ti-5Mo-5V-8Cr-3A1, Ti-13V-11Cr-3Al, Ti-2.25Al-11Sn-5Zr-1Mo-0.2Si, Ti-6Al-2Zr-1Mo-1V, Ti-15V-3Cr-3Sn-3Al or Ti-8Al-1Mo-1V;

[0009] the nickel alloy is Inconel 600, Inconel 601, Inconel 625, Inconel 690, Inconel718, Inconel 800, Inconel 825, Inconel 901, Hastelloy B, Hastelloy C, Hastelloy X, Hastelloy R or Hastelloy G.

[0010] In some of these embodiments, the porosity of the porous metal plate raw material is 20%-80%, and / or the gas permeability of the porous metal plate is 0.2×10 -12 m 2 ~5×10 -12 m 2 and / or the thickness uniformity of the porous metal plate is ±(1% - 3%)μm of the nominal value of the porous metal plate thickness, and / or the intrinsic contact resistance of the porous metal plate is 0.5 - 1.2 mΩ@2 MPa.

[0011] A preparation method for preparing the composite porous metal plate includes the following steps:

[0012] Pre-treat the porous metal plate, and the pre-treatment is used for surface cleaning of the porous metal plate;

[0013] Perform surface hydrophilic treatment on the pre-treated porous metal plate to construct the hydrophilic treatment layer;

[0014] Fabricate a mask according to the shape of the hydrophilic region;

[0015] Cover the mask on the surface of the hydrophilic treatment layer, and construct the hydrophobic treatment layer on the surface region of the hydrophilic treatment layer not covered by the mask to obtain a workpiece to be processed;

[0016] Remove the mask plate, and sinter and heat-treat the workpiece to be processed in an oxygen-free environment to obtain the composite porous metal plate.

[0017] In some embodiments, the surface hydrophilic treatment includes an acid pickling process.

[0018] In some embodiments, the acid used in the acid pickling process is an aqueous solution of oxalic acid, sulfuric acid, hydrochloric acid, or phosphoric acid, and the mass concentration of the aqueous solution is 2% to 16%.

[0019] In some embodiments, during the acid pickling process, the acid pickling temperature is 50°C to 90°C, and the acid pickling time is 5 min to 60 min.

[0020] In some embodiments, the sintering is carried out by pressureless sintering, hot pressing sintering or rolling sintering.

[0021] In some embodiments, the sintering heat treatment is carried out in an inert atmosphere or a vacuum environment, the heating rate of the sintering heat treatment is 0.1°C to 50°C per minute, the holding temperature of the sintering heat treatment is 200°C to 500°C, the holding time of the sintering heat treatment is 0.5 h to 3 h, and after the holding is completed, it is cooled naturally.

[0022] Compared with the prior art, the present invention has the following beneficial effects:

[0023] (1) The composite porous metal plate provided by the present invention has hydrophilic regions and hydrophobic regions, simultaneously realizing hydrophilic and hydrophobic functions, and is suitable for electrolytic hydrogen production. Among them, the hydrophilic regions can effectively transport liquids, and the hydrophobic regions can effectively exclude gases, realizing the efficient transport of reactants and the efficient transfer of reaction products, so that the electrochemical reaction is more sufficient, the reaction efficiency is higher, and it has good electrical conductivity and mechanical properties, providing technical support for cost reduction and efficiency improvement in the field of electrolytic water hydrogen production;

[0024] (2) Compared with other preparation processes of the prior art, the preparation method provided by the present invention is simple to operate and does not generate impurities that affect the service life of the electrolytic cell. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a schematic structural diagram of the use state of the composite porous metal plate in Embodiments 1 and 2 of the present invention;

[0026] Figure 2 It is a schematic structural diagram of the disconnection of the composite porous metal plate in Embodiments 1 and 2 of the present invention;

[0027] Figure 3 It is a schematic structural diagram of the use state of the composite porous metal plate in Embodiments 3 and 4 of the present invention;

[0028] Figure 4 Contact angle test results of the hydrophilic region in Example 1 of the present invention;

[0029] Figure 5 Contact angle test results of the hydrophobic region in Example 1 of the present invention.

[0030] Among them, the reference numerals are: 1, porous metal plate; 2, hydrophilic treatment layer; 3, hydrophobic treatment layer; 4, membrane electrode. Specific embodiments

[0031] To clearly illustrate the technical features of the present solution, the following will combine the drawings and embodiments to detail the implementation manners of the present application, so as to fully understand how the present application uses technical means to solve technical problems and the implementation process of achieving corresponding technical effects and implement accordingly. Each feature in the embodiments of the present application and the embodiments can be combined with each other on the premise of not conflicting, and the formed technical solutions are all within the protection scope of the present application.

[0032] It is worth noting that the methods used in the present invention are all conventional methods without special regulations; the raw materials and devices used are all conventional commercially available products without special regulations, and their sources are not specifically limited.

[0033] See the attached Figure 2 In the embodiments of the present invention, a composite porous metal plate is provided, including a porous metal plate 1, a hydrophilic treatment layer 2 and a hydrophobic treatment layer 3. The hydrophilic treatment layer 2 is constructed on the surface of the porous metal plate 1 and the hydrophobic treatment layer 3 is constructed on a partial area of the surface of the hydrophilic treatment layer 2. At least one hydrophobic region is formed on the surface of the hydrophobic treatment layer 3. See Figure 1 、 2 、3. At least one hydrophobic region divides the surface of the hydrophilic treatment layer 2 into at least two hydrophilic regions. The area ratio of at least one hydrophobic region is 30% - 50%, and the area ratio of at least two hydrophilic regions is 50% - 70%. The contact angle of the hydrophilic region is less than 90°, and the contact angle of the hydrophobic region is greater than 120°. When in use, the composite porous metal plate is laid on the membrane electrode 4.

[0034] In some embodiments, the hydrophobic treatment layer 3 is an amorphous structure coating, and the thickness of the amorphous structure coating is 10 nm - 200 nm.

[0035] In some embodiments, the substrate of the amorphous structure coating is palladium-based, platinum-based, titanium-based, or zirconium-based, and the additive elements of the amorphous structure coating are palladium, platinum, titanium, zirconium, tantalum, nickel, iron, carbon, nitrogen, or phosphorus.

[0036] In some embodiments, the material of the porous metal plate 1 is titanium, nickel, titanium alloy, nickel alloy or stainless steel.

[0037] In some of these embodiments, the titanium alloy is Ti-6Al-4V, Ti-5Al-2.5Sn, Ti-6Al-7Nb, Ti-3Al-2.5V, Ti-2Al-2.5Zr, Ti-8Mn, Ti-6Al-6V-2Sn, Ti-6Al-2Sn-4Zr-6Mo, Ti-6Al-2Sn-4Zr-2Mo, Ti-6Al-2Sn-2Zr-2Mo, Ti-3Al-5Mo-4.5V, Ti-6Al-2Sn-4Zr-2Mo, Ti-5Mo-5V-8Cr-3A1, Ti-13V-11Cr-3Al, Ti-2.25Al-11Sn-5Zr-1Mo-0.2Si, Ti-6Al-2Zr-1Mo-1V, Ti-15V-3Cr-3Sn-3Al or Ti-8Al-1Mo-1V;

[0038] The nickel alloy is Inconel 600, Inconel 601, Inconel 625, Inconel 690, Inconel 718, Inconel 800, Inconel 825, Inconel 901, Hastelloy B, HastelloyC, Hastelloy X, Hastelloy R or Hastelloy G.

[0039] In some of these embodiments, the porosity of the raw material of the porous metal plate 1 is 20% - 80%, and / or the gas permeability of the porous metal plate 1 is 0.2×10 -12 m 2 ~5×10 -12 m 2 , and / or the thickness uniformity of the porous metal plate 1 is ±(1% - 3%)μm of the nominal value of the thickness of the porous metal plate 1, and / or the intrinsic contact resistance of the porous metal plate 1 is 0.5 - 1.2 mΩ@2 MPa.

[0040] A preparation method for preparing a composite porous metal plate, comprising the following steps:

[0041] Pre-treat the porous metal plate 1, and the pre-treatment is for surface cleaning of the porous metal plate 1;

[0042] The pre-treatment steps are: first, completely immerse the porous metal plate 1 in an anhydrous ethanol solution for ultrasonic surface cleaning treatment to remove impurities such as oil stains and dust attached to the surface; completely immerse the porous metal plate after the ultrasonic surface cleaning treatment in deionized water for at least 3 times of ultrasonic vibration treatment to achieve further cleaning treatment of the porous metal plate 1; place the porous metal plate 1 after the ultrasonic vibration treatment in a fume hood to air dry naturally to complete the pre-treatment of the porous metal plate;

[0043] Perform surface hydrophilic treatment on the pretreated porous metal plate to construct a hydrophilic treatment layer 2;

[0044] In some embodiments, the surface hydrophilic treatment includes an acid pickling process (the acid pickling process is also called a surface hydroxylation treatment process). The acid used in the acid pickling process is an aqueous solution of oxalic acid, sulfuric acid, hydrochloric acid, or phosphoric acid. The mass concentration of the aqueous solution is 2-16%. During the acid pickling process, the acid pickling temperature is 50°C-90°C, and the acid pickling time is 5 min-60 min.

[0045] Fabricate a mask according to the shape of the hydrophilic region; preferably, use a numerically controlled machine tool to precisely control the preparation of masks with different grid parameters from high-temperature resistant materials, where the longitudinal grid size or the transverse grid size is 0.2 mm-2 mm respectively;

[0046] Cover the mask on the surface of the hydrophilic treatment layer 2, and construct a hydrophobic treatment layer 3 on the surface region of the hydrophilic treatment layer 2 not covered by the mask to obtain a pretreated part; preferably, construct a hydrophobic treatment layer 3 on the surface region of the hydrophilic treatment layer 2 not covered by the mask by magnetron sputtering to obtain a pretreated part;

[0047] Remove the mask, and perform sintering heat treatment on the pretreated part in an oxygen-free environment to enhance the bonding force between the hydrophobic surface layer and the porous metal plate, and obtain a composite porous metal plate.

[0048] In some embodiments, sintering is carried out by pressureless sintering, hot pressing sintering or rolling sintering.

[0049] In some embodiments, the sintering heat treatment is carried out in an inert atmosphere or a vacuum environment, and the heating rate of the sintering heat treatment is 0.1°C-50°C / minute, and the holding temperature of the sintering heat treatment is 200°C-500°C, and the holding time of the sintering heat treatment is 0.5 h-3 h, and after the holding is completed, it is cooled naturally.

[0050] Example 1;

[0051] A composite porous metal plate and a preparation method, the preparation method comprising the following steps:

[0052] (1) Prepare a titanium fiber felt with a thickness of 0.25 mm and a porosity of 50% as the porous metal plate 1;

[0053] (2) Immerse the porous metal plate 1 made of titanium fiber felt completely in an absolute ethanol solution for ultrasonic surface cleaning to remove impurities such as oil stains and dust adhering to the surface; immerse the porous metal plate 1 after the ultrasonic surface cleaning completely in deionized water for at least 3 times of ultrasonic vibration treatment to achieve further cleaning of the porous metal plate 1; place the porous metal plate 1 after the ultrasonic vibration treatment in a fume hood to air dry naturally to complete the pretreatment of the porous metal plate 1;

[0054] (3) Prepare an oxalic acid solution with a mass concentration of 10%. Place the pretreated porous metal plate 1 in the oxalic acid solution for pickling. Set the pickling temperature to 80 °C and the pickling time to 20 min to obtain a porous metal plate with a hydrophilic treatment layer 2 constructed on the surface;

[0055] (4) Use a numerical control machine tool to cut a strip-shaped mask plate on a PET sheet with a thickness of 0.25 mm. The strip width is 0.5 mm, and the length of the strip matches the length of the porous metal plate;

[0056] (5) Cover the mask plate on the surface of the hydrophilic treatment layer 2, and construct an amorphous structure coating on the surface area of the hydrophilic treatment layer 2 not covered by the mask plate through magnetron sputtering to obtain a pre-treatment piece. That is, in this embodiment, the hydrophobic treatment layer 3 is an amorphous structure coating, where the substrate of the amorphous structure coating is Fe-Si-B, and the additive elements of the amorphous structure coating include 80% by mass of Fe and 20% by mass of Si or B elements, and the deposition thickness of the amorphous structure coating is 100 nm;

[0057] (6) Remove the mask plate, and perform sintering heat treatment on the pre-treatment piece in an argon atmosphere. The heating rate of the sintering heat treatment is 1 °C / min, the temperature of the sintering heat treatment is 300 °C, and the holding time of the sintering heat treatment is 60 min; then cool down naturally to obtain a composite porous metal plate.

[0058] For the composite porous metal plate prepared by this method, the hydrophobic regions and hydrophilic regions are distributed in a strip-shaped alternating pattern. Refer to Figure 1 , 4 hydrophobic regions are formed on the surface of the hydrophobic treatment layer 3. The 4 hydrophobic regions divide the surface of the hydrophilic treatment layer 2 into 4 hydrophilic regions. The area ratio of the 4 hydrophobic regions is 50%, and the area ratio of the 4 hydrophilic regions is 50%. Refer to Figure 4 , where the contact angle of the hydrophilic region is 50°. Refer to Figure 5 The contact angle of the hydrophobic region is 150°.

[0059] Example 2;

[0060] A composite porous metal plate and a preparation method, the preparation method includes the following steps:

[0061] (1) Prepare a titanium fiber felt with a thickness of 0.5 mm and a porosity of 70% as the porous metal plate 1;

[0062] (2) Immerse the porous metal plate 1 made of titanium fiber felt completely in an anhydrous ethanol solution for ultrasonic surface cleaning treatment to remove impurities such as oil stains and dust attached to the surface; immerse the porous metal plate 1 after the ultrasonic surface cleaning treatment completely in deionized water for at least 3 times of ultrasonic vibration treatment to achieve further cleaning treatment of the porous metal plate 1; place the porous metal plate 1 after the ultrasonic vibration treatment in a fume hood to air dry naturally to complete the pretreatment of the porous metal plate 1;

[0063] (3) Prepare a sulfuric acid solution with a mass concentration of 15%, place the pretreated porous metal plate 1 in an oxalic acid solution for pickling, set the pickling temperature at 90 °C, and set the pickling time at 15 min to obtain a porous metal plate with a hydrophilic treatment layer 2 constructed on the surface;

[0064] (4) Use a numerical control machine tool to cut a strip-shaped mask plate on a 0.5-mm-thick PET sheet, with the strip width being 0.5 mm and the length of the strip matching the length of the porous metal plate;

[0065] (5) Cover the mask plate on the surface of the hydrophilic treatment layer 2, and construct an amorphous structure coating on the surface area of the hydrophilic treatment layer 2 not covered by the mask plate through magnetron sputtering to obtain a pre-treatment piece. That is, in this embodiment, the hydrophobic treatment layer 3 is an amorphous structure coating, where the substrate of the amorphous structure coating is Fe-Si-B, and the additive elements of the amorphous structure coating include 80% by mass of Fe and 20% by mass of Si or B elements, and the deposition thickness of the amorphous structure coating is 100 nm;

[0066] (6) Remove the mask plate, and perform sintering heat treatment on the pre-treatment piece in an argon atmosphere, where the heating rate of the sintering heat treatment is 1 °C / min, the temperature of the sintering heat treatment is 300 °C, and the holding time of the sintering heat treatment is 60 min; then cool down naturally to obtain a composite porous metal plate.

[0067] For the composite porous metal plate prepared by this method, the hydrophobic regions and hydrophilic regions are distributed in a strip-shaped alternating pattern. Refer to Figure 1 , 4 hydrophobic regions are formed on the surface of the hydrophobic treatment layer 3, and the 4 hydrophobic regions divide the surface of the hydrophilic treatment layer 2 into 4 hydrophilic regions. The area ratio of the 4 hydrophobic regions is 50%, and the area ratio of the 4 hydrophilic regions is 50%. Among them, the contact angle of the hydrophilic region is 32°, and the contact angle of the hydrophobic region is 162°.

[0068] Example 3;

[0069] A composite porous metal plate and a preparation method, the preparation method comprising the following steps:

[0070] (1) Prepare a titanium fiber felt with a thickness of 0.25 mm and a porosity of 50% as the porous metal plate 1;

[0071] (2) Immerse the porous metal plate 1 made of titanium fiber felt completely in an anhydrous ethanol solution for ultrasonic surface cleaning to remove impurities such as oil stains and dust attached to the surface; Immerse the porous metal plate 1 after the ultrasonic surface cleaning completely in deionized water for at least 3 times of ultrasonic vibration treatment to achieve further cleaning of the porous metal plate 1; Place the porous metal plate 1 after the ultrasonic vibration treatment in a fume hood to dry naturally to complete the pretreatment of the porous metal plate 1;

[0072] (3) Prepare an oxalic acid solution with a mass concentration of 10%, place the pretreated porous metal plate 1 in the oxalic acid solution for pickling, set the pickling temperature to 90 °C, and set the pickling time to 10 min to obtain a porous metal plate with a hydrophilic treatment layer 2 constructed on the surface;

[0073] (4) Use a numerical control machine tool to cut a rectangular mask plate on a PET plate with a thickness of 0.25 mm, and the rectangular size is 1 mm * 1 mm;

[0074] (5) Cover the mask plates on the surface of the hydrophilic treatment layer 2 at intervals, and the uncovered areas of the mask plates are in a grid pattern. Construct an amorphous structure coating on the surface area of the hydrophilic treatment layer 2 not covered by the mask plates by magnetron sputtering to obtain a pre-treatment piece, where the substrate of the amorphous structure coating is Fe-Si-B, and the additive elements of the amorphous structure coating include 80% by mass of Fe and 20% by mass of Si or B elements, and the deposition thickness of the amorphous structure coating is 100 nm;

[0075] (6) Remove the mask plate, and perform sintering heat treatment on the pre-treatment piece in an argon atmosphere, where the heating rate of the sintering heat treatment is 1 °C / min, the temperature of the sintering heat treatment is 400 °C, and the holding time of the sintering heat treatment is 30 min; Then cool down naturally to obtain a composite porous metal plate.

[0076] For the composite porous metal plate prepared by this method, the hydrophobic regions are in a grid pattern, and the hydrophilic regions are rectangular and spaced apart from each other. Refer to Figure 3 , one hydrophobic region is formed on the surface of the hydrophobic treatment layer 3, and one hydrophobic region divides the surface of the hydrophilic treatment layer 2 into 12 hydrophilic regions. The area ratio of one hydrophobic region is 50%, and the area ratio of the 12 hydrophilic regions is 50%. Among them, the contact angle of the hydrophilic region is 39°, and the contact angle of the hydrophobic region is 146°.

[0077] Example 4;

[0078] A composite porous metal plate and a preparation method thereof. The preparation method comprises the following steps:

[0079] (1) Prepare a rolled porous metal titanium plate with a thickness of 0.5 mm and a porosity of 30% as the porous metal plate 1;

[0080] (2) Immerse the porous metal plate 1 made of rolled porous metal titanium plate completely in an anhydrous ethanol solution for ultrasonic surface cleaning treatment to remove impurities such as oil stains and dust attached to the surface; Immerse the porous metal plate 1 after the ultrasonic surface cleaning treatment completely in deionized water for at least 3 times of ultrasonic vibration treatment to achieve further cleaning treatment of the porous metal plate 1; Place the porous metal plate 1 after the ultrasonic vibration treatment in a fume hood to air dry naturally to complete the pretreatment of the porous metal plate 1;

[0081] (3) Configure an oxalic acid solution with a mass concentration of 10%, place the pretreated porous metal plate 1 in the oxalic acid solution for pickling, set the pickling temperature to 90 °C, and set the pickling time to 10 min to obtain a porous metal plate with a hydrophilic treatment layer 2 constructed on the surface;

[0082] (4) Use a numerical control machine tool to cut a rectangular mask plate on a PET sheet with a thickness of 0.25 mm, and the rectangular size is 2 mm * 1 mm;

[0083] (5) Cover the mask plates on the surface of the hydrophilic treatment layer 2 at intervals. The uncovered areas of the mask plates are in a grid pattern. Construct an amorphous structure coating on the surface area of the hydrophilic treatment layer 2 not covered by the mask plates by means of magnetron sputtering to obtain a pre-treatment piece. That is, in this embodiment, the hydrophobic treatment layer 3 is an amorphous structure coating, wherein the material of the amorphous structure coating is Zr-Ni-Cu-Al, and the deposition thickness of the amorphous structure coating is 50 nm;

[0084] (6) Remove the mask plate, and perform sintering heat treatment on the pre-treatment piece in an argon atmosphere. The heating rate of the sintering heat treatment is 10 °C / min, the temperature of the sintering heat treatment is 500 °C, and the holding time of the sintering heat treatment is 60 min; Then cool down naturally to obtain the composite porous metal plate.

[0085] For the composite porous metal plate prepared by this method, the hydrophobic areas are in a grid pattern, and the hydrophilic areas are rectangular and spaced from each other. Refer to Figure 3 , one hydrophobic area is formed on the surface of the hydrophobic treatment layer 3. One hydrophobic area divides the surface of the hydrophilic treatment layer 2 into 12 hydrophilic areas. The area ratio of one hydrophobic area is 66%, and the area ratio of the 12 hydrophilic areas is 34%. Among them, the contact angle of the hydrophilic area is 27°, and the contact angle of the hydrophobic area is 136°.

[0086] Finally, it should be noted that the above content is only used to illustrate the technical solution of the present invention, rather than limiting the protection scope of the present invention. Any simple modification or equivalent replacement made by those of ordinary skill in the art to the technical solution of the present invention shall not depart from the essence and scope of the technical solution of the present invention.

Claims

1. A composite porous metal plate, characterized in that: It includes a porous metal plate, a hydrophilic treatment layer, and a hydrophobic treatment layer. The hydrophilic treatment layer is constructed on the surface of the porous metal plate, and the hydrophobic treatment layer is constructed on a partial area of the surface of the hydrophilic treatment layer. At least one hydrophobic area is formed on the surface of the hydrophobic treatment layer. The at least one hydrophobic area divides the surface of the hydrophilic treatment layer into at least two hydrophilic areas. The area ratio of the at least two hydrophilic areas is 50% - 70%, and the area ratio of the at least one hydrophobic area is 30% - 50%. The contact angle of the hydrophilic area is less than 90°, and the contact angle of the hydrophobic area is greater than 120°.

2. The composite porous metal plate according to claim 1, characterized in that: The hydrophobic treatment layer is an amorphous structure coating, and the thickness of the amorphous structure coating is 10nm - 200nm.

3. The composite porous metal plate according to claim 2, wherein: The substrate of the amorphous structure coating is palladium-based, platinum-based, titanium-based, or zirconium-based, and the additive elements of the amorphous structure coating are palladium, platinum, titanium, zirconium, tantalum, nickel, iron, carbon, nitrogen, or phosphorus.

4. The composite porous metal plate according to claim 1, wherein: The material of the porous metal plate is titanium, nickel, titanium alloy, nickel alloy, or stainless steel.

5. The composite porous metal plate according to claim 1, wherein: The porosity of the porous metal plate raw material is 20%-80%, and / or, the gas permeability of the porous metal plate is 0.2×10 -12 m 2 ~5×10 -12 m 2 , and / or, the thickness uniformity of the porous metal plate is ±(1% - 3%)μm of the nominal value of the porous metal plate thickness, and / or, the intrinsic contact resistance of the porous metal plate is 0.5 - 1.2 mΩ@2 MPa.

6. A preparation method for preparing the composite porous metal plate according to any one of claims 1-5, characterized in that: It includes the following steps: Pretreat the porous metal plate; Perform surface hydrophilic treatment on the pretreated porous metal plate to construct the hydrophilic treatment layer; Make a mask according to the shape of the hydrophilic area; Cover the mask on the surface of the hydrophilic treatment layer, and construct the hydrophobic treatment layer on the surface area of the hydrophilic treatment layer not covered by the mask to obtain a workpiece to be processed; Remove the mask, and perform sintering heat treatment on the workpiece to be processed in an oxygen-free environment to obtain the composite porous metal plate.

7. The preparation method according to claim 6, characterized in that: The surface hydrophilic treatment includes an acid pickling process.

8. The preparation method according to claim 7, wherein: The acid used in the acid pickling process is an aqueous solution of oxalic acid, sulfuric acid, hydrochloric acid, or phosphoric acid, and the mass concentration of the aqueous solution is 2% - 16%.

9. The preparation method according to claim 7, characterized in that: During the acid pickling process, the acid pickling temperature is 50°C - 90°C, and the acid pickling time is 5min - 60min.

10. The preparation method according to claim 6, characterized in that: The sintering adopts pressureless sintering, hot press sintering, or rolling sintering.

11. The preparation method according to claim 6 or 10, characterized in that: The sintering heat treatment is carried out in an inert atmosphere or a vacuum environment. The heating rate of the sintering heat treatment is 0.1°C - 50°C / minute, the holding temperature of the sintering heat treatment is 200°C - 500°C, the holding time of the sintering heat treatment is 0.5h - 3h, and it is cooled naturally after the holding ends.

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