Embedded thermoelectric hydrogel electrolyte, preparation method thereof and application of embedded thermoelectric hydrogel electrolyte in hydrogen production by using waste heat of data center

Abstract

The invention discloses an embedded thermoelectric hydrogel electrolyte, a preparation method thereof and an application of the embedded thermoelectric hydrogel electrolyte in hydrogen production by using waste heat of a data center, and low-grade waste heat is directly converted into electric energy to drive water decomposition by embedding a thermoelectric material into a solid hydrogel electrolyte with adjustable water content. Meanwhile, an integrated system is constructed by adopting a chemical cross-linking process, a thermoelectric module is integrated, and the size of the device is reduced; the platinum-based cathode and the graphene anode are combined, and zero-carbon-emission hydrogen production is realized by taking water as a raw material, so that an efficient, compact and low-cost solution is provided for green transformation of a data center and collaborative development of hydrogen energy economy.

Description

Technical Field

[0001] The present invention belongs to the field of energy and environmental engineering technology, and specifically relates to an embedded thermoelectric hydrogel electrolyte, a preparation method thereof, and an application in hydrogen production using waste heat from data centers. Background Art

[0002] The high energy consumption and carbon emissions of data centers have become a key challenge hindering the rapid development of the digital economy. The majority of data center energy consumption comes from computing and cooling equipment, generating a large amount of waste heat. However, much of this waste heat is wasted and not effectively recycled. Therefore, effectively utilizing waste heat generated by data centers has become a pressing energy issue.

[0003] As a clean energy source, hydrogen plays a vital role in the global energy transition. Traditional hydrogen production methods, such as fossil fuel reforming and water electrolysis, suffer from low energy efficiency and environmental pollution. Therefore, developing a system that can efficiently and cleanly produce hydrogen is crucial for addressing both energy and environmental challenges.

[0004] Although there are some water electrolysis hydrogen production systems in the existing technology, there is still much room for improvement due to the low energy utilization efficiency, especially in the use of waste heat for hydrogen production. Summary of the Invention

[0005] The purpose of this section is to summarize some aspects of the embodiments of the present invention and briefly introduce some preferred embodiments. Some simplifications or omissions may be made in this section and the abstract and title of this application to avoid obscuring the purpose of this section, the abstract and the title of the invention, and such simplifications or omissions should not be used to limit the scope of the present invention.

[0006] In view of the above problems and / or the problems existing in the prior art, the present invention is proposed.

[0007] Therefore, the purpose of the present invention is to overcome the deficiencies in the prior art and provide a method for preparing an embedded thermoelectric hydrogel electrolyte.

[0008] In order to solve the above technical problems, the present invention provides the following technical solutions: comprising:

[0009] Dissolve choline chloride and sodium hydroxide in deionized water and stir to obtain a clear liquid;

[0010] Polyvinyl alcohol, deacetylated glucomannan, and polyacrylic acid are added to a clear and transparent liquid to form a solution precursor;

[0011] adding the ball-milled thermoelectric material to a solution precursor to obtain a mixture, and adding a functional additive to the mixture to obtain a suspension;

[0012] The suspension is placed in an oven and heated to achieve cross-linking and curing to obtain an embedded thermoelectric hydrogel electrolyte.

[0013] As a preferred solution of the method for preparing the embedded thermoelectric hydrogel electrolyte of the present invention, the molar ratio of choline chloride to sodium hydroxide is 1:1-5.

[0014] As a preferred solution of the method for preparing the embedded thermoelectric hydrogel electrolyte of the present invention, the usage ratio of the polyvinyl alcohol, deacetylated glucomannan, and polyacrylic acid is 5-7:1:1-18.

[0015] As a preferred solution of the method for preparing the embedded thermoelectric hydrogel electrolyte of the present invention, the content of choline chloride in the solution precursor is 10-15%, and the content of polyvinyl alcohol is 5-10%.

[0016] As a preferred embodiment of the preparation method of the embedded thermoelectric hydrogel electrolyte of the present invention, the thermoelectric material includes one or more of PbTe, Bi2Te3 or Mg2Si, and the ball milling treatment refines the grains to 50-100 nm, and the addition amount is 15-20 wt% of the solution precursor.

[0017] As a preferred embodiment of the method for preparing the embedded thermoelectric hydrogel electrolyte of the present invention, the functional additives include a cross-linking agent, an initiator, and NaCl, and the cross-linking agent includes glutaraldehyde or N,N′

[0018] -methylenebisacrylamide, initiators include hydrochloric acid or ammonium persulfate.

[0019] As a preferred solution of the method for preparing the embedded thermoelectric hydrogel electrolyte of the present invention, the heating temperature of the suspension is 45-55° C. and the heating time is 1.5-2 hours.

[0020] Another object of the present invention is to provide an application of an embedded thermoelectric hydrogel electrolyte in hydrogen production using waste heat from a data center.

[0021] In order to solve the above technical problems, the present invention provides the following technical solutions: comprising:

[0022] The embedded thermoelectric hydrogel electrolyte is placed in the waste heat environment of the data center. The hydrogel electrolyte absorbs the waste heat to form a temperature difference, and the thermoelectric material generates an electric potential difference. The electric potential difference is guided through the electrolytic cell to drive the water decomposition reaction.

[0023] The cathode of the electrolytic cell is composed of platinum and ruthenium in a mass ratio of 3:1; the anode is made of a porous carbon framework and loaded with carbon nanotubes or graphene; the electrolyte is potassium hydroxide (KOH) aqueous solution;

[0024] During the electrolysis process, a constant voltage of 1.5 to 2.5 V and a current density of 8 to 12 mA / cm2 are applied across the electrodes;

[0025] The cathode region is physically separated from the anode region by a Nafion membrane, and hydrogen is generated at the cathode and oxygen is generated at the anode.

[0026] As a preferred solution for the application of the embedded thermoelectric hydrogel electrolyte of the present invention in hydrogen production using waste heat from a data center, the waste heat environment has a temperature difference of 40 to 90°C.

[0027] Beneficial effects of the present invention:

[0028] 1. Efficient waste heat utilization:

[0029] The present invention organically combines hydrogel with thermoelectric material, uses the hydrogel to efficiently absorb waste heat and activate water molecules, and uses the thermoelectric material embedded in the hydrogel to generate an electric potential difference in situ, thereby simultaneously reducing the internal resistance of the system and the overpotential for hydrogen production, and efficiently utilizing waste heat to electrolyze hydrogen. It can directly convert waste heat of 40 to 90°C into electrical energy to drive the water decomposition reaction, significantly improving the efficiency of waste heat utilization.

[0030] 2. Green hydrogen production:

[0031] This method significantly improves the ionic conductivity of the solid hydrogel electrolyte by adding a 1:1 mixed solution of choline chloride (ChCl) and sodium hydroxide (NaOH) to the traditional hydrogel preparation method, and works in synergy with thermoelectric materials. The low-grade waste heat from the data center at 40 to 90°C is then used to directly drive water electrolysis to produce hydrogen. This method uses water and waste heat as raw materials and has zero carbon emissions throughout the process. It efficiently converts waste heat into hydrogen energy, increasing energy utilization efficiency by over 30%, significantly reducing data center energy consumption and carbon footprint, meeting the requirements of green energy development and adapting to global energy transition trends.

[0032] 3. Strong system adaptability:

[0033] It is suitable for waste heat environments in data centers of different sizes, does not require additional energy input, and reduces operating costs.

[0034] 4. Compact structure and low cost:

[0035] The embedded design makes the system compact and occupies little space, while significantly reducing equipment costs and maintenance expenses.

[0036] 5. Significant economic and environmental benefits:

[0037] The present invention can stably produce high-purity hydrogen under waste heat conditions, with an hourly hydrogen production of 1.5 to 125 m3. 3 , which has broad industrial application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. Those skilled in the art can also derive other drawings based on these drawings without inventive effort. Among them:

[0039] Figure 1 This is a schematic diagram of the process of preparing an embedded thermoelectric hydrogel electrolyte and using the waste heat generated by cloud computing data center servers to perform embedded thermoelectric electrolysis to produce hydrogen. DETAILED DESCRIPTION

[0040] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described in detail below in conjunction with the embodiments of the specification.

[0041] In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention may also be implemented in other ways different from those described herein. Those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0042] Secondly, the term "one embodiment" or "embodiment" herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The phrase "in one embodiment" appearing in various places throughout this specification does not necessarily refer to the same embodiment, nor does it refer to a separate or selective embodiment that is mutually exclusive of other embodiments.

[0043] Unless otherwise specified, the raw materials and reagents of the present invention are commonly available in the market.

[0044] Polyvinyl alcohol (PVA, ≥99%), choline chloride (ChCl, AR), sodium hydroxide (NaOH, AR), deacetylated glucomannan (DAGM, AR), polyacrylic acid (PAA, AR), glutaraldehyde (GA, AR), hydrochloric acid (HCl, AR), ammonium persulfate (APS, AR), sodium chloride (NaCl, AR), acrylic acid (AA, AR), platinum (P), ruthenium (Ru), iridium (Ir), and polypropylene plastic were obtained from Sinopharm Chemical Reagent Co., Ltd. Graphene was purchased from Changzhou Sixth Element Materials Technology Co., Ltd.

[0045] The electrical equipment in the entire hydrogen production process of the present invention complies with national electrical safety standards to ensure the safe operation of the equipment; at the same time, waste heat is isolated and controlled to avoid damage to the system caused by excessive temperature.

[0046] Example 1

[0047] This embodiment provides a method for preparing an embedded thermoelectric hydrogel electrolyte, specifically:

[0048] 1) Weigh 7.78 g of choline chloride (ChCl) and 2.22 g of sodium hydroxide (NaOH) in a molar ratio of 1:1, dissolve them in 50 mL of deionized water and stir until a clear liquid is obtained;

[0049] 2) adding 5 g of polyvinyl alcohol (PVA), 0.8 g of deacetylated glucomannan (DAGM), and 3 mL of polyacrylic acid (PAA) to the above-mentioned transparent liquid to form a solution precursor;

[0050] 3) Add 15 wt% of the thermoelectric material Bi2Te3 (Bi2Te3 and grinding balls are loaded into a ball mill and ball milled for 10 hours to refine the grain size to 100 nm) to the solution precursor, and ultrasonically vibrate at 85°C for 4 hours to ensure thorough mixing and form a uniform solution I;

[0051] 4) Add a crosslinker and an initiator to solution I. The crosslinker is 0.35 mL of 50% glutaraldehyde and the initiator is 0.25 mL of 1.2 mol·L -1 The obtained suspension was placed in a vacuum drying oven and heated at 55°C for 2 hours to solidify, thereby forming a hydrogel. After the curing process, it was soaked in deionized water to obtain the solid hydrogel electrolyte of this embodiment. The water content of the hydrogel electrolyte was 70% and the ionic conductivity was 11S / m.

[0052] Example 2

[0053] This embodiment provides a method for preparing an embedded thermoelectric hydrogel electrolyte, specifically:

[0054] 1) Weigh 7.78 g of choline chloride (ChCl) and 2.22 g of sodium hydroxide (NaOH) in a molar ratio of 1:1, dissolve them in 50 mL of deionized water and stir until a clear liquid is obtained;

[0055] 2) 5 g of polyvinyl alcohol (PVA), 0.8 g of deacetylated glucomannan (DAGM), and 3 mL of polyacrylic acid (PAA) were added to the above-mentioned transparent liquid to form a solution precursor. The mass percentages of the components in the gel precursor solution were 39.5% (ChCl), 11.3% (NaOH), 25.4% (PVA), 4.1% (DAGM), and 19.8% (PAA), respectively.

[0056] 3) 15 wt% of the thermoelectric material Bi2Te3 (Bi2Te3 and grinding balls were placed in a ball mill and ball milled for 10 hours to refine the grains to 100 nm) was added to the gel precursor solution, and the resulting mixture was ultrasonically oscillated at 85°C for 4 hours to ensure sufficient mixing and form a uniform solution I.

[0057] 4) A crosslinker and an initiator were added to solution I. The crosslinker was 0.02 g N,N′-methylenebisacrylamide (MBA) and the initiator was 0.03 g ammonium persulfate (APS). After continuous stirring, the resulting mixture was placed in an ultrasonic cleaner for 10 minutes. After removing bubbles, the mixture was placed in a vacuum drying oven and heated at 55° C. for 2 hours to form a gel electrolyte. 1.17 g NaCl was added to enhance ionic conductivity. The hydrogel had a water content of 75% and a conductivity of 18 S / m.

[0058] Comparative Example 1

[0059] The difference between this comparative example and Example 1 is that choline chloride ChCl and sodium hydroxide are not added, and the remaining steps and processes are the same as those in Example 1, thereby obtaining a solid hydrogel electrolyte of this comparative example. The hydrogel electrolyte has a water content of 67% and a conductivity of 5 S / m.

[0060] Comparative Example 2

[0061] The difference between this comparative example and Example 1 is that the amount of deionized water in step 1) is adjusted from 50 ml to 40 ml, and the remaining steps and processes are the same as those in Example 1 to obtain the gel electrolyte of this example.

[0062] Comparative Example 3

[0063] The difference between this comparative example and Example 1 is that the thermoelectric material Bi2Te3 in step 4) is adjusted to GeTe, and the remaining steps and processes are the same as those in Example 1 to obtain the gel electrolyte of this example.

[0064] Comparative Example 4

[0065] The difference between this comparative example and Example 1 is that the thermoelectric material Bi2Te3 in step 4) is adjusted to AgSbTe2, and the remaining steps and processes are the same as those in Example 1 to obtain the gel electrolyte of this example.

[0066] Comparative Example 5

[0067] The difference between this embodiment and embodiment 1 is that the thermoelectric material Bi2Te3 in step 3) is adjusted to PbTe, and the remaining steps and processes are the same as those in embodiment 1 to obtain the gel electrolyte of this embodiment.

[0068] Comparative Example 6

[0069] The difference between this embodiment and embodiment 2 is that the thermoelectric material Bi2Te3 in step 4) is adjusted to Mg2Si, and the remaining steps and processes are the same as those in embodiment 1 to obtain the gel electrolyte of this embodiment.

[0070] Example 3

[0071] This embodiment provides a method for producing hydrogen through embedded thermoelectric electrolysis using waste heat generated by cloud computing data center servers. Specifically:

[0072] 1) The hydrogel electrolyte is placed in the waste heat environment of a data center, which typically generates a temperature difference of 40 to 90°C. The hydrogel electrolyte absorbs the waste heat to create a temperature difference, and the thermoelectric material generates an electric potential difference, which is used to drive the subsequent water splitting reaction.

[0073] 2) Driving the water splitting reaction by directing the potential difference through the electrolytic cell, wherein:

[0074] The cathode is made of an alloy material made of platinum (Pt) and ruthenium (Ru) in a mass ratio of 3:1, which is loaded on a titanium mesh substrate to improve conductivity and stability.

[0075] The anode is made of a porous carbon framework and loaded with carbon nanotubes (CNTs) or graphene nanosheets to increase the specific surface area and enhance catalytic activity;

[0076] The electrolyte is a 0.5 mol / L potassium hydroxide (KOH) aqueous solution, prepared with deionized water to ensure sufficient ionic conductivity;

[0077] During the electrolysis process, a constant voltage of 2.0 V was applied across the electrodes, the reaction temperature was maintained at room temperature (25°C), the current density was controlled at approximately 10 mA / cm2, and the reaction time was 12 h;

[0078] The electrolytic cell is made of acrylic plastic, with a length, width and height of 400 mm, 300 mm and 180 mm respectively.

[0079] 3) During the reaction, hydrogen is generated at the cathode and oxygen is generated at the anode, and the generated hydrogen and oxygen are collected separately through a gas separation device.

[0080] The hydrogel electrolytes prepared in Examples 1 to 4 and Comparative Examples 1 to 4 were used to produce hydrogen by thermoelectric electrolysis according to the method of this embodiment. The amounts of hydrogen and oxygen generated by different hydrogel electrolytes are shown in Table 1.

[0081] Table 1

[0082]

[0083]

[0084] As can be seen from Table 1, by comparing multiple embodiments with comparative examples, the present invention systematically verifies the significant impact of key materials and process parameters on hydrogen production performance. By introducing choline chloride (ChCl) and sodium hydroxide (NaOH) in a 1:1 molar ratio, the present invention improves the ionic conductivity of the solid hydrogel, increasing the conductivity from 5 S / m to a maximum of 18 S / m, significantly enhancing the efficiency of the water splitting reaction.

[0085] Selecting different types of thermoelectric materials further improved the hydrogel's thermal conductivity and hydrogen production capacity, producing 125.4L of hydrogen per hour, demonstrating the critical importance of thermoelectric material selection for system performance. In contrast, the control example, which did not add ChCl / NaOH or replace other thermoelectric materials, showed a significant decrease in conductivity and hydrogen production, only 1 / 20 of that in the example, demonstrating the significant effectiveness of this approach in improving thermoelectric conversion efficiency and system electrolysis performance.

[0086] In addition, when the same thermoelectric material is embedded, by adjusting the cross-linker, initiator and adding NaCl, significant differences can be produced in the hydrogel network microstructure and ion transmission channels, resulting in a significant increase in electrolyte conductivity and gas production. The microscopic pore structure of the hydrogel will affect ion migration and thus affect conductivity. Compared with Example 2, the hydrogel prepared by the method of Example 1 is interconnected and porous and has good pore uniformity. The addition of Nacl can not only improve the ionic conductivity, but also make the pore network of the hydrogel more uniform, significantly improving the ion transmission efficiency. Therefore, the technical effect of Example 1 is significantly better than that of Example 3. This shows that the type of cross-linker, initiation mechanism and addition of Nacl in the hydrogel preparation method are key parameters affecting the technical effect in this technology.

[0087] Example 6

[0088] This embodiment differs from Example 1 in that the molar ratios of choline chloride and sodium hydroxide are adjusted to 0.75:1, 1:1, and 1.25:1, respectively. The remaining steps are the same as those in Example 1 to obtain the gel electrolyte of this embodiment. The application effects of each electrolyte are measured with reference to Example 3, and the results are shown in Table 2.

[0089] Table 2

[0090] molar ratio Hydrogen production L / h 0.75:1 48.7 1:1 125.4 1.25:1 101.2

[0091] Example 7

[0092] The difference between this embodiment and Example 1 is that the addition amount of the thermoelectric material relative to the solution precursor is adjusted to 10, 15, and 20 wt%, respectively. The remaining steps are the same as those in Example 1 to obtain the gel electrolyte of this embodiment. The application effects of each electrolyte are measured with reference to Example 3, and the results are shown in Table 3.

[0093] Table 3

[0094] Addition amount Hydrogen production L / h 10 82.5 15 125.4 20 109.8

[0095] It can be seen from Tables 2 and 3 that different molar ratios of choline chloride and sodium hydroxide and the amount of thermoelectric material added will have a significant effect on the performance of the obtained electrolyte. When the molar ratio of choline chloride and sodium hydroxide is 5% and the amount of thermoelectric material added is 15wt%, the electrical conductivity and hydrogen production rate both reach the maximum value.

[0096] In summary, the present invention cleverly utilizes the low-grade waste heat of data centers to achieve clean, efficient, and low-carbon hydrogen production, has excellent economic and environmental benefits, is in line with the green energy and dual-carbon development strategies, and reflects strong industrial application prospects and technology promotion value.

[0097] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims

1. A method for preparing an embedded thermoelectric hydrogel electrolyte, characterized in that: include, Dissolve choline chloride and sodium hydroxide in deionized water and stir to obtain a clear liquid; Polyvinyl alcohol, deacetylated glucomannan, and polyacrylic acid are added to a clear and transparent liquid to form a solution precursor; adding the ball-milled thermoelectric material to a solution precursor to obtain a mixture, and adding a functional additive to the mixture to obtain a suspension; The suspension is placed in an oven and heated to achieve cross-linking and curing to obtain an embedded thermoelectric hydrogel electrolyte.

2. The method for preparing an embedded thermoelectric hydrogel electrolyte according to claim 1, wherein: The molar ratio of the choline chloride to the sodium hydroxide is 1:1-5.

3. The method for preparing an embedded thermoelectric hydrogel electrolyte according to claim 1, wherein: The usage ratio of the polyvinyl alcohol, deacetylated glucomannan and polyacrylic acid is 5-7:1:1-18.

4. The method for preparing an embedded thermoelectric hydrogel electrolyte according to claim 1, wherein: The content of choline chloride in the solution precursor is 10-15%, and the content of polyvinyl alcohol is 5-10%.

5. The method for preparing an embedded thermoelectric hydrogel electrolyte according to claim 1, wherein: The thermoelectric material includes one or more of PbTe, Bi2Te3 or Mg2Si, and the ball milling process refines the grains to 50-100 nm. The addition amount is 15-20 wt% of the solution precursor.

6. The method for preparing an embedded thermoelectric hydrogel electrolyte according to claim 1, wherein: The functional auxiliary agent includes a cross-linking agent, an initiator, and NaCl. The cross-linking agent includes glutaraldehyde or N,N'-methylenebisacrylamide, and the initiator includes hydrochloric acid or ammonium persulfate.

7. The method for preparing an embedded thermoelectric hydrogel electrolyte according to claim 1, wherein: The heating temperature of the suspension is 45-55° C., and the heating time is 1.5-2 hours.

8. The embedded thermoelectric hydrogel electrolyte prepared by the preparation method according to any one of claims 1 to 7, characterized in that: The water content of the electrolyte is 60% to 80%, and the conductivity is 0.1 to 1 S / m.

9. Application of the embedded thermoelectric hydrogel electrolyte according to claim 8 in hydrogen production using waste heat from a data center, characterized in that: The method of application includes, The hydrogel electrolyte described in claim 8 is placed in a waste heat environment of a data center. The hydrogel electrolyte forms a temperature difference by absorbing waste heat, and the thermoelectric material generates an electric potential difference. The electric potential difference is guided through the electrolytic cell to drive the water decomposition reaction, wherein: The cathode of the electrolytic cell is composed of platinum and ruthenium in a mass ratio of 3:1; the anode is made of a porous carbon framework and loaded with carbon nanotubes or graphene; the electrolyte is potassium hydroxide (KOH) aqueous solution; During the electrolysis process, a constant voltage of 1.5 to 2.5 V is applied to both ends of the electrode, and 8 to 12 mA / cm 2 The current density; The cathode region is physically separated from the anode region by a Nafion membrane, and hydrogen is generated at the cathode and oxygen is generated at the anode.

10. Application of the embedded thermoelectric hydrogel electrolyte according to claim 9 in hydrogen production using waste heat from a data center, characterized in that: The waste heat environment has a temperature difference of 40 to 90°C.

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