Moisture power generation device and preparation method and application thereof

Abstract

The invention discloses a moisture power generation device and a preparation method and application thereof, the moisture power generation device comprises a core layer, a shell layer and at least two groups of electrodes, the core layer is made of a water-absorbing material and is used for absorbing moisture and generating charges through interaction between the moisture and ions in the core layer; the shell layer wraps the core layer, is made of a conductive and waterproof material and is used for conducting charges generated by the core layer; the two groups of electrodes are respectively arranged on two sides of the shell layer, are connected with the shell layer and are used for leading out charges conducted by the shell layer; the moisture power generation device has the efficient moisture adsorption capacity, moisture resources in the environment can be fully utilized, the power generation efficiency is improved, meanwhile, the device further has the stable structural design so as to resist interference of external environment factors, the performance can be kept stable, good durability is achieved, and the requirement for long-term stable power generation is met.

Description

Technical Field

[0001] The present invention relates to the technical field of moisture power generation, and particularly relates to a moisture power generation device, a preparation method thereof, and an application thereof. Background Art

[0002] With the increasing global demand for clean energy, moisture power generation, as a new energy conversion method, has gradually become prominent. Moisture in the environment is ubiquitous, and converting it into electrical energy has great potential value. However, the existing moisture power generation technologies currently face many challenges, which limit their efficiency and application scope.

[0003] The current moisture power generation devices have a relatively simple structure, but there is still a large room for improvement in their energy conversion efficiency. For example, a patent with the publication number CN114665747B provides a soil film and a moisture power generation device and its application. The soil film is composed of dry soil particles; among them, the dry soil particles are prepared by drying, grinding, and sieving wetland bottom mud; the soil moisture power generation device includes: a top electrode, a bottom electrode, and a soil film, wherein one side surface of the soil film is closely connected to the top electrode, and the other side surface is closely connected to the bottom electrode. This device can continuously utilize the moisture in the air to generate an open-circuit voltage of 0 - 0.4 volts and a short-circuit current of 0 - 0.1 microamps, and has the advantages of being pollution-free, clean, sustainable, and having almost unlimited power generation conditions.

[0004] However, the existing moisture power generation materials have limited moisture adsorption capacity and cannot fully utilize the moisture resources in the environment, which leads to low power generation efficiency. In addition, during the long-term operation of the moisture power generation device, due to the lack of effective structural design, it is easily affected by external environmental factors, such as excessive moisture loss or penetration, resulting in unstable performance and poor durability, and it is difficult to meet the requirements of long-term stable power generation. Summary of the Invention

[0005] The purpose of the present invention is to overcome the above technical deficiencies, and propose a moisture power generation device, a preparation method thereof, and an application thereof, so as to solve the technical problems in the prior art that the moisture power generation device has low power generation efficiency, unstable performance, poor durability, and is difficult to meet the requirements of long-term stable power generation.

[0006] To achieve the above technical objectives, the present invention adopts the following technical solutions: In a first aspect, the present invention provides a moisture power generation device, comprising: a core layer, a shell layer, and at least two sets of electrodes. The core layer is made of a water-absorbing material, which is used to absorb moisture and generate charges through the interaction between the moisture and the ions in the core layer. The shell layer wraps around the outside of the core layer and is made of a conductive and waterproof material, which is used to conduct the charges generated by the core layer. The two sets of electrodes are respectively arranged on both sides of the shell layer and are connected to the shell layer, which is used to export the charges conducted by the shell layer.

[0007] Among them, the core layer can effectively absorb moisture in the environment. After the moisture is absorbed, the ions in the core layer material will interact with the moisture to form charged ions. After absorbing moisture, the positive and negative ions will migrate to different regions of the core layer respectively, and the charge separation will form a potential difference (voltage) inside the core layer, providing a driving force for power generation. Since the shell layer has conductivity, these charges will be conducted through the shell layer. Finally, the charges are exported through the electrodes on both sides of the shell layer to form a current.

[0008] In some embodiments, the water-absorbing material of the core layer is a porous water-absorbing polymer.

[0009] In some embodiments, the shell layer is a composite film prepared from a conductive agent, where the conductive agent is at least one of pyrrole, carbon nanotube powder, graphene, carbon nanotubes, Mxene, superconducting carbon black, and acetylene black.

[0010] In some embodiments, the electrodes are made of a metal material or a conductive material with excellent conductivity, preferably metal electrodes.

[0011] In a second aspect, the present invention provides a preparation method of a moisture power generation device for preparing the moisture power generation device described in any one of the above, comprising the following steps: S1: Mix the raw materials of the porous water-absorbing polymer in deionized water, and form a porous structure through a freeze-thaw cycle to obtain the core layer; S2: Disperse the conductive agent in an organic solvent, add a polymer binder and zinc oxide, stir evenly, and then use the solution casting method to cast the solution on the surface of the core layer and dry it; S3: Deposit the electrodes on both sides of the shell layer by physical vapor deposition and control the deposition thickness.

[0012] In some embodiments, in step S1, the porous water-absorbing polymer is made of one or more composites of polyvinyl alcohol, polyacrylic acid, polyaniline, and sodium alginate.

[0013] In some embodiments, in step S2, zinc oxide with a mass ratio of 0-2:100 to the polymer binder is further added to the organic solvent, and the mass ratio of the polymer binder to the conductive agent is 10-100:1.

[0014] In some embodiments, in step S2, the organic solvent is at least one of N-methylpyrrolidone, N,N-dimethylformamide, N,N-dimethylacetamide, and acetone, the polymer binder is polyvinylidene fluoride, and the mass fraction of the polymer binder is 5%-15% of the organic solvent.

[0015] In some embodiments, in step S3, the electrode is a silver or copper electrode, and its deposition thickness is between 100-500 nm.

[0016] In a third aspect, the present invention provides an application of the above-mentioned moisture power generation device in power generation.

[0017] Compared with the prior art, the moisture power generation device, its preparation method and application provided by the present invention have the following advantages: the highly water-absorbent material in the core layer of the moisture power generation device can efficiently absorb moisture in the environment and generate charges, which can provide a water source for the power generation process, improve the utilization rate of moisture, and thus enhance the power generation efficiency; the shell layer is wrapped outside the core layer and has conductivity and waterproofness, which not only ensures the effective utilization of moisture, but also can effectively conduct the generated charges, effectively improving the stability and durability of the device, so that the performance of the device is not easily degraded during long-term use; the moisture power generation device has a high moisture adsorption capacity, can make full use of the moisture resources in the environment to improve the power generation efficiency, and at the same time, the device also has a stable structural design to resist the interference of external environmental factors, maintain stable performance, and has good durability to meet the requirements of long-term stable power generation.

[0018] Through the preparation method provided by the present invention, the structure and performance of the device can be precisely controlled, and the preparation process is relatively simple, without the need for complex equipment and processes, and is easy to realize industrial large-scale production, having good application prospects. Description of the Drawings

[0019] Figure 1 is a three-dimensional structural schematic diagram of the moisture power generation device provided by an embodiment of the present invention; Figure 2 is a cross-sectional structural schematic diagram of the moisture power generation device provided by an embodiment of the present invention.

[0020] Description of the reference numerals: 1, core layer; 2, shell layer; 3, electrode. Detailed Embodiments

[0021] In order to make the objectives, technical solutions and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0022] To solve the technical problems of low power generation efficiency, unstable performance and poor durability of the moisture power generation device, which are difficult to meet the requirements of long-term stable power generation, the present invention provides a moisture power generation device, its preparation method and application. The moisture power generation device has high moisture adsorption capacity, can make full use of the moisture resources in the environment, improve the power generation efficiency. At the same time, the device also has a stable structural design to resist the interference of external environmental factors, maintain stable performance, and has good durability to meet the requirements of long-term stable power generation.

[0023] In a first aspect, referring to Figure 1 and Figure 2 , the present invention provides a moisture power generation device, including: a core layer 1, a shell layer 2 and at least two groups of electrodes 3.

[0024] The core layer 1 is made of a highly water-absorbent material. For example, it can be a porous water-absorbent polymer, which has a rich pore structure and can quickly absorb moisture from the environment, providing an abundant water source for the power generation process.

[0025] The shell layer 2 is wrapped outside the core layer 1 and is composed of a material with good electrical conductivity and certain waterproof properties. The shell layer 2 has two main functions. One is to limit the moisture absorbed by the core layer 1 within a suitable range to prevent excessive moisture loss or uncontrolled diffusion; the other is to effectively collect the charges generated by the interaction between the core layer 1 and the moisture and conduct them out.

[0026] Further, in some possible embodiments, the shell layer 2 is a composite film prepared from a conductive agent, where the conductive agent is at least one of pyrrole, carbon nanotube powder, graphene, carbon nanotubes, Mxene, superconducting carbon black, and acetylene black.

[0027] Preferably, the composite film is a graphene composite film.

[0028] The two groups of electrodes 3 are respectively arranged on both sides of the shell layer 2. The electrodes 3 are made of a metal material or a conductive material with excellent electrical conductivity, preferably metal electrodes, such as silver electrodes or copper electrodes. The electrodes 3 are in close contact with the shell layer 2, and their function is to export the charges conducted by the shell layer 2, thereby connecting to an external circuit to realize the effective utilization of electric energy.

[0029] In a second aspect, the present invention provides a preparation method of a moisture power generation device for preparing the moisture power generation device described in any one of the above embodiments, including the following steps: Step 1: Core layer preparation The preparation of core layer 1 is a key step, which determines the performance of the final product. In order to ensure the quality of the product, core layer 1 is made of highly absorbent materials, preferably porous absorbent polymers. For example, polyvinyl alcohol (PVA) / polyacrylic acid (PAA) hydrogel is selected as core layer 1, which has excellent water absorption and good mechanical properties. The preparation process of PVA / PAA hydrogel is as follows: acrylic acid, 8g of H2SO4 solution with a concentration of 0.8mol / L, polyvinyl alcohol and a-ketoglutaric acid (0.6wt% of acrylic acid monomer) are added to a flask, and magnetic stirring is used to fully dissolve them; the solution is injected into a homemade glass plate mold and irradiated with a UV lamp (365nnl, 300W) for 6h; then it is placed in a -20℃ environment and frozen for 12h, and thawed at room temperature to obtain PVA / PAA hydrogel; during the preparation process, the mixing ratio of polyvinyl alcohol and acrylic acid needs to be precisely controlled to ensure the uniformity and water absorption performance of the material. For example, different ratios such as 6:1, 8:1, 9:2, 9:1 (mass ratio) can be used for mixing to achieve the best performance effect.

[0030] In the preparation of the core layer 1, the combination of polyvinyl alcohol and polyacrylic acid can produce a synergistic effect, enhancing the water absorption and mechanical strength of the material. In addition, the prepared hydrogel can maintain a specific shape, which is consistent with the shape of the mold used. By selecting different molds, solidification and molding can be performed according to requirements. The choice of mold is based on the desired shape and size of the core layer 1, which will directly affect the appearance and applicability of the final product.

[0031] It should be noted that the mixed solution needs to be fully stirred to ensure that the polyvinyl alcohol and acrylic acid are completely and evenly mixed, so as to promote uniform crystallization and mold casting of the material during the freezing process. By implementing a freeze-thaw cycle, the mixed solution can be prompted to form a porous structure. The formation principle of this porous structure is as follows: during the freeze-thaw cycle, water crystallizes to form ice crystals, and then the ice crystals melt during the thawing stage, leaving gaps and channels. These gaps and channels form the basis of the porous structure, which significantly increases the specific surface area of ​​the material, thereby improving its water absorption performance.

[0032] The porous water-absorbent polymer prepared in the present application as the core layer 1 material not only has high water absorption, but also has low density and good mechanical strength due to its porous structure. These characteristics make the core layer 1 material excellent in absorbing and retaining water, providing ideal performance for various applications, and also providing a stable physical basis for the wet gas power generation device, which helps to improve the energy conversion efficiency and stability.

[0033] Step 2: Shell preparation The shell layer 2 is made of a material with good electrical conductivity and certain waterproofness, such as a graphene composite film. The preparation process is as follows: First, prepare a graphene dispersion. Graphene is uniformly dispersed in an organic solvent, and N-methylpyrrolidone (NMP) can be used as the organic solvent. By methods such as ultrasonic treatment, mechanical stirring, and adding a dispersant, ensure that a uniform graphene dispersion is obtained. Subsequently, an appropriate amount of polymer binder and zinc oxide are added to the dispersion; optionally, the mass ratio of zinc oxide to the polymer binder is 0-2% (m / m), and ensure uniform mixing. Polyvinylidene fluoride (PVDF) can be used as the polymer binder. Then, using the solution casting method, the mixed solution is uniformly cast on the surface of the core layer 1 material. The specific operation is to lay the core layer 1 material flat on a flat substrate, slowly pour the graphene composite solution onto the surface of the core layer 1, and finally dry it in an oven at 60°C for 12 hours to ensure firm bonding between the shell layer 2 material and the core layer 1.

[0034] It should be noted that the PVDF membrane without added zinc oxide exhibits a disordered and irregular finger-like pore structure, and the porosity is relatively low. As the content of nano-ZnO gradually increases, the thickness of the finger-like pore support layer of the membrane decreases, and the arrangement of the finger-like pore structure tends to be regular. However, when the ZnO content is too high, the morphology of the membrane pore structure becomes uneven and collapses. This is because excessive nano-ZnO particles limit the cross-linking effect between PVDF molecules; while the addition of an appropriate amount of nano-ZnO can increase the membrane pore size, thereby increasing the pure water flux. However, when the content of nano-ZnO increases excessively, the membrane flux does not increase accordingly. This may be because a large number of nanoparticles change the pore structure of the membrane, or excessive nanoparticles in the casting solution agglomerate, resulting in the membrane flux not increasing or even decreasing; therefore, the introduction of nano-ZnO can enhance the mechanical properties of the membrane, improve the strength and toughness of the membrane, and at the same time the anti-fouling performance of the membrane is also improved. However, when the nano-ZnO content is too high, due to the agglomeration phenomenon between nanoparticles and the change in the stability of the casting solution, the anti-fouling performance of the modified membrane will decrease.

[0035] Using polyvinylidene fluoride (PVDF) as the polymer binder, PVDF mainly serves as a hydrophobic porous top layer in moisture power generation, allowing the evaporated steam to pass through while preventing water from absorbing solar radiation, thereby avoiding the attenuation of the moisture gradient and water migration rate in the hydrogel due to excessive evaporation during the day. At night, the radiative cooling effect of PVDF reduces the adsorption temperature of the hydrogel, accelerates water adsorption, and helps to establish a stable adsorption-desorption cycle during the day-night alternation.

[0036] ZnO mainly serves as a humidity-sensitive component in moisture power generation. It regulates the interfacial potential of the heterostructure through Grotthuss proton hopping, significantly reducing the diffusion barrier for proton migration in ZnO and GO, and effectively improving the response rate of the moisture power generation device (GZMEG) to moisture and the persistent electrical output ability.

[0037] Step 3: Electrode Installation Electrodes 3 are arranged on both sides of the core-shell structure. The material of the electrodes 3 can be a metal electrode, such as a silver electrode or a copper electrode. The installation process is as follows: Use the physical vapor deposition (PVD) method to deposit a silver electrode or a copper electrode on both sides of the material of the shell layer 2. During the deposition process, it is necessary to strictly control the deposition thickness, generally controlled between 100 - 500 nm, to ensure that the electrode 3 has good electrical conductivity and stability, and at the same time ensure a tight contact between the electrode 3 and the shell layer 2.

[0038] This application prepares the PVA / PAA hydrogel by ultraviolet light-initiated polymerization. In some embodiments, the presence of sulfuric acid (H 2 SO 4 ) can inhibit the ionization of carboxyl groups (-COOH) on the polyacrylic acid (PAA) polymer chain. In this way, more active sites are provided for the formation of hydrogen bonds between carboxyl groups, between carboxyl groups and hydroxyl groups (-OH) on the polyvinyl alcohol (PVA) chain. The freeze-thaw process can further promote the formation of intermolecular or intramolecular hydrogen bonds of the polymer PVA molecules, thereby enhancing the mechanical strength of the hydrogel. Immerse the PVA / PAA hydrogel in an iron ion (Fe³ + ) solution, and the excess carboxylate ions (COO - ) in the hydrogel network can coordinate and complex with Fe³ + , and then a secondary cross-linked network is constructed. Finally, immerse this hydrogel with a double cross-linked network in water to make it fully swell, promoting the formation of a more stable tridentate coordination complex structure between COO - and Fe³ + , so as to obtain the hydrogel with the best mechanical properties. In the network structure of the hydrogel, hydrogen bonds and coordination bonds act as reversible "sacrificial" bonds, providing an energy dissipation mechanism for the hydrogel, which enables the hydrogel to have the characteristics of high strength and high toughness.

[0039] The following combines 7 examples to elaborate in detail on the process of preparing the PVA / PAA hydrogel and the moisture power generation device.

[0040] Example 1 Preparation of the core layer 1: Add 3 g of acrylic acid, 8 g of H2SO4 solution with a concentration of 0.8 mol / L, 0.3 g of polyvinyl alcohol, and α-ketoglutaric acid (0.6 wt% of the acrylic acid monomer) into a flask, and magnetically stir to dissolve it fully; inject the solution into a self-made glass plate mold, and irradiate it with an ultraviolet lamp (365 nm, 300 W) for 6 h; then place it in an environment of -20 °C for 12 h and thaw at room temperature to obtain a porous water-absorbing PVA / PAA hydrogel as the core layer 1 material.

[0041] Preparation of Shell Layer 2: First, prepare a graphene dispersion. Disperse 2% graphene in the organic solvent N-methylpyrrolidone (NMP), and use ultrasonic means or the like to ensure the formation of a uniform graphene dispersion. Add 10% polyvinylidene fluoride (PVDF) and 0.5% ZnO to the graphene dispersion, and heat and stir evenly. Then, use the solution casting method to cast it on the surface of the core layer 1 material. The specific process is to place the core layer 1 material on a flat substrate, slowly cast the graphene composite solution on the surface of the core layer 1, and finally dry it in an oven at 60°C for 12 hours to firmly attach the shell layer 2 material to the core layer 1.

[0042] Installation of Electrode 3: Select a copper electrode, and deposit a silver electrode on both sides of the shell layer 2 by physical vapor deposition (PVD), with a deposition thickness of 300 nm.

[0043] Performance Test: Place the prepared moisture power generation device in an environment with a humidity of 80%, and connect it to a circuit with an external resistance of 100 Ω. After testing, the device can generate a stable voltage, and the voltage value is between 0.5 - 1.5 V. Moreover, after continuous operation for 100 hours, the performance of the device does not decrease significantly and can still generate electricity stably.

[0044] Example 2 A preparation method of a moisture power generation device, other contents are the same as those in Example 1. The difference is that the preparation of the core layer 1 is as follows: Add 3 g of acrylic acid, 8 g of H2SO4 solution with a concentration of 0.8 mol / L, 0.4 g of polyvinyl alcohol, and α-ketoglutaric acid (0.6 wt% of the acrylic acid monomer) to a flask, and stir magnetically to dissolve it fully; inject the solution into a self-made glass plate mold, and irradiate it with an ultraviolet lamp (365 nm, 300 W) for 6 h; then place it in an environment at -20°C and freeze it for 12 h, and thaw it at room temperature to obtain a porous water-absorbing PVA / PAA hydrogel as the core layer 1 material. In addition, when preparing the shell layer 2, the ZnO content is changed to 1%, and the electrode 3 is selected as a silver electrode with a deposition thickness of 400 nm.

[0045] Performance Test: Place the device in an environment with a humidity of 90%, and connect it to a circuit with an external resistance of 50 Ω. The test results show that the voltage generated by this device is between 0.8 - 2.0 V, and after continuous operation for 150 hours, the performance can still remain above 90% of the initial performance, demonstrating good stability.

[0046] Example 3 A preparation method of a moisture power generation device, other contents are the same as those in Example 1. The difference is that when preparing the core layer 1, the mass of PVA is changed to 0.45 g, and in addition, when preparing the shell layer 2, the ZnO content is changed to 2%.

[0047] Performance test: Place the device in an environment with a humidity of 85%, and connect it to a circuit with an external resistance of 80 Ω. The test results show that the voltage generated by the device is between 0.6 - 1.8 V. After continuous operation for 120 hours, the performance remains above 92% of the initial performance. This indicates that the device has good stability and durability.

[0048] Example 4 A preparation method of a moisture power generation device, other contents are the same as those in Example 1, except that when preparing the core layer 1, the mass of PVA is changed to 0.6 g.

[0049] Shell layer 2: Use a composite film made by mixing graphene with a new polymer binder (such as styrene-butadiene rubber (SBR)) as the material of shell layer 2.

[0050] Electrode 3: Use a copper electrode with a deposition thickness of 200 nm.

[0051] Performance test: Place it in an environment with a humidity of 75%, and connect it to a circuit with an external resistance of 120 Ω. It is found that the voltage generated by the device is between 0.4 - 1.2 V. After continuous operation for 80 hours, the performance of the device only drops by about 5%. This indicates that the device in Example 4 can generate electricity effectively in a lower humidity environment and has good durability by adjusting the mass ratio of PVA in the core layer 1 and using a new shell layer 2 material. These improvements help to broaden the application scope of the device to some extent, making it applicable to more variable environmental conditions.

[0052] Example 5 A preparation method of a moisture power generation device, other contents are the same as those in Example 1, except that when preparing the core layer 1, the mass of PVA is changed to 0.5 g, and at the same time, a small amount of nano-silica (SiO 2 2) (accounting for 5% of the total mass) is added to the mixed solution to enhance water absorption.

[0053] Shell layer 2: The material of shell layer 2 is a graphene–PVDF–ZnO composite film, but carbon nanotubes (CNT) (accounting for 10% of the mass of graphene) are added during the preparation process to improve conductivity.

[0054] Electrode 3: Select a silver electrode with a deposition thickness of 300 nm.

[0055] Performance test: In an environment with a humidity of 90%, connect it to a circuit with an external resistance of 40 Ω. The voltage generated by the device is between 1.0 - 2.2 V. After continuous operation for 180 hours, the performance of the device can still remain above 95% of the initial performance. This shows that in a test environment with a higher humidity (90%), the device can still maintain high efficiency and stability, indicating its good environmental adaptability. This improvement in efficiency is partly attributed to the added SiO2 , the water absorption of the core layer 1 is improved, and when CNT is introduced into the graphene–PVDF-ZnO composite film, the conductivity of the shell layer 2 is significantly improved, which helps to improve the charge conduction efficiency. The improvement of both is crucial for improving the moisture power generation efficiency.

[0056] Example 6 A preparation method of a moisture power generation device, the other contents are the same as those in Example 1, except that the prepared porous water-absorbing PVA / PAA hydrogel is immersed in an FeCl3 solution of 0.2 mol / L hydrochloric acid for 20 h to obtain a PVA / PAA / Fe3+ hydrogel.

[0057] Among them, in the process of preparing the multi-component hydrogel, the PVA / PAA hydrogel containing aniline monomer is immersed in an ammonium persulfate solution with a certain acid concentration to enable the in-situ polymerization of aniline in the hydrogel to form a conductive PANI network. During this process, the color of the hydrogel will change, from transparent to dark green, and finally to black. In the network structure of the hydrogel, intermolecular or intramolecular hydrogen bonds will form between the hydroxyl group (OH) of PVA and the carboxyl group (COOH) of PAA, which is part of the hydrogel network structure. At the same time, the imine (NH) on polyaniline will also form hydrogen bonds with the carboxyl group (COOH) on polyacrylic acid and the hydroxyl group (OH) of PVA. The formation of these hydrogen bonds has an important impact on the performance of the hydrogel. During the synthesis process, the formation of polyaniline not only provides the hydrogel with electrical conductivity, but also the hydrogen bond interaction mainly serves as a physical cross-linking point in the hydrogel network structure, providing the main energy dissipation mechanism for the hydrogel, thereby improving the mechanical properties of the hydrogel. This preparation method of the multi-component hydrogel realizes the synergistic improvement of mechanical properties and electrical conductivity through the interaction between different components, providing a guarantee for the high performance of the moisture power generation device.

[0058] Performance test: The prepared moisture power generation device is placed in an environment with a humidity of 80%, and connected to a circuit with an external resistance of 100 Ω. After testing, it is found that the device can generate a stable voltage, and the voltage value is between 0.5 - 1.6 V. And after continuous operation for 110 hours, the performance of the device does not decrease significantly and can still generate electricity stably. This shows that by cross-linking the PVA / PAA hydrogel with the Fe³ + solution, the performance of the moisture power generation device can be significantly improved. This cross-linking not only enhances the mechanical strength of the hydrogel, but also improves the durability and stability of the device. Therefore, this preparation method provides an effective way to improve the performance of the moisture power generation device and is expected to be widely used in the field of clean energy.

[0059] Example 7 A preparation method of a moisture power generation device, the other contents are the same as those in Example 1, the difference is that the nuclear layer 1 is prepared as follows: Add 3 g of acrylic acid, 8 g of H2SO4 solution with a concentration of 0.8 mol / L, 0.3 g of polyvinyl alcohol, a-ketoglutaric acid (0.6 wt% of the acrylic acid monomer), and aniline (the amine accounts for 16.6% of the total monomer mass content) into a flask, and stir magnetically to dissolve it fully; Inject the solution into a self-made glass plate mold, and irradiate it with an ultraviolet lamp (365 nm, 300 W) for 6 h; Then place it in a -20 °C environment and freeze for 12 h, and thaw at room temperature to obtain a PVA / PAA hydrogel containing aniline monomers; Then soak the hydrogel in an ammonium persulfate solution containing 1 mol / L of H2SO4 for 42 h to obtain a PVA / PAA / PANI hydrogel.

[0060] Performance test: Place the prepared moisture power generation device in an environment with a humidity of 80%, and connect it to a circuit with an external resistance of 110 Ω. Through testing, it is found that the device can generate a stable voltage, and the voltage value is between 0.8 - 2.0 V. And after continuous operation for 120 hours, the performance of the device does not decrease significantly and can still generate electricity stably. This shows that by combining PVA, PAA, and PANI together, the prepared multi-component hydrogel not only enhances the mechanical properties and conductivity of the hydrogel, but also improves the electrical output stability and durability of the device. This preparation method provides an effective way for the development of high-performance moisture power generation devices and is expected to be applied in the field of sustainable energy.

[0061] Among them, the improvement of mechanical properties is attributed to: PVA itself has good film-forming properties and mechanical properties, and hydrogen bonds can be formed between its molecular chains, which helps to enhance the overall structural strength of the hydrogel. Due to the presence of its carboxyl group (-COOH), PAA can, on the one hand, form hydrogen bonds with the hydroxyl group (-OH) on the PVA molecular chain, and on the other hand, its own structure can be further strengthened through the interaction between carboxyl groups. PANI is a conductive polymer. When it combines with PVA and PAA, it may penetrate into the network structure formed by PVA and PAA. The interaction between PANI molecular chains and the chemical bonding or physical entanglement with PVA and PAA enable the hydrogel to more effectively disperse stress when subjected to external forces, thereby enhancing mechanical properties.

[0062] Among them, the increase in conductivity is attributed to the following: PANI is a conductive polymer with a conjugated structure, which can itself provide a channel for electron conduction. In the multi-component hydrogel, the binding mode of PANI with PVA and PAA helps to form a continuous conductive path. The molecular chain of PANI can interact with the carboxyl group of PAA or the hydroxyl group of PVA, enabling electrons to be transmitted more effectively inside the hydrogel. At the same time, the presence of PVA and PAA changes the microenvironment around PANI, which is conducive to increasing its conductivity. In the moisture power generation device, the increase in conductivity is directly related to the power generation efficiency of the device. When the hydrogel absorbs moisture, the ions or electrons in the moisture need to be rapidly conducted inside the hydrogel in order to effectively convert chemical energy into electrical energy. A higher conductivity can reduce the energy loss during the charge transfer process, enabling more charges to flow between the electrodes 3 of the device, thereby increasing the electrical output.

[0063] Among them, the increase in stability is attributed to the following: The hydrogen bonds between PVA and PAA and the interaction between PANI and them can prevent the hydrogel from undergoing excessive swelling or shrinkage when the humidity changes, thus maintaining the stability of the internal charge transfer channels. In addition, the presence of PANI helps to stabilize the charge distribution in the hydrogel, enabling the generation and transmission of electrons to proceed continuously and stably during the moisture power generation process.

[0064] Among them, the increase in durability is attributed to the following: The chemical structures of PVA and PAA are relatively stable. Although PANI is a conductive polymer, its overall chemical stability is also improved after being compounded with PVA and PAA. The good mechanical properties of the multi-component hydrogel also contribute to its durability. During long-term use, the hydrogel will not lose its power generation ability due to physical wear or structural damage.

[0065] Comparative Example 1 A preparation method of a moisture power generation device, with other contents being the same as in Example 1, except that instead of using a highly absorbent material with a porous structure, PVA is directly used as the core layer 1 material.

[0066] Performance test: Placed in an environment with a humidity of 80%, connected to a circuit with an external resistance of 100 Ω. It was found that the voltage generated by the device was relatively low, between 0.2 - 0.8 V, and after continuously working for 50 hours, the performance decreased significantly, only maintaining about 60% of the initial performance.

[0067] Comparative Example 2 A preparation method of a moisture power generation device, with other contents being the same as in Example 1, except that for the shell layer 2, an insulating ordinary polymer film (such as a polyethylene film) is used instead of the graphene composite film. Electrode 3: A copper electrode is used, with a deposition thickness of 300 nm.

[0068] Performance test: In an environment with a humidity of 85%, a circuit with an external resistance of 80 Ω is connected. Since the shell layer 2 is non-conductive, almost no effective voltage output can be generated, and the normal power generation function cannot be achieved.

[0069] Comparative Example 3 A preparation method of a moisture power generation device, other contents are the same as those in Example 1, the difference is that instead of using a metal electrode, a graphite electrode 3 is used.

[0070] Performance test: In an environment with a humidity of 90%, a circuit with an external resistance of 50 Ω is connected. It is found that due to the lower conductivity of the graphite electrode 3 than that of the metal electrode, the voltage generated by the device is between 0.3 - 1.0 V, which is much lower than the voltage when using the metal electrode. And after continuous operation for 100 hours, the performance drops rapidly, and only about 70% of the initial performance can be maintained.

[0071] Comparative Example 4 A preparation method of a moisture power generation device, other contents are the same as those in Example 1, the difference is that nano-zinc oxide is not added during the preparation process of the shell layer 2.

[0072] Performance test: The prepared moisture power generation device is placed in an environment with a humidity of 80%, and a circuit with an external resistance of 100 Ω is connected. After testing, it is found that compared with the example, the device without ZnO generates a slightly lower voltage, and the voltage value is lower than the range of 0.5 - 1.5 V. Because the lack of ZnO reduces the conductivity and overall performance of the shell layer 2, and at the same time, after continuous operation for 100 hours, the performance of the device drops more significantly because the absence of ZnO affects the stability and durability of the device. In summary, the preparation method of the shell layer 2 without adding ZnO results in a decrease in the performance of the moisture power generation device, especially in terms of voltage output and durability. The addition of ZnO plays an important role in improving conductivity and stability.

[0073] Comparative Example 5 A preparation method of a moisture power generation device, other contents are the same as those in Example 1, the difference is that during the preparation process of the core layer 1, the ratio of PVA and PAA is adjusted to 3:2, and PAA is replaced by SA, and at the same time, CaCl2 is added as a cross-linking agent (accounting for 0.8% of the mass of PVA).

[0074] Among them, CaCl 2 As a cross-linking agent (accounting for 0.8% of the mass of PVA), it will undergo an ionic cross-linking reaction with the carboxyl group in SA. Ca² +Ions can bind to the carboxyl groups on multiple SA chains to form a cross-linked network structure. This cross-linked network plays a role in enhancing the structural stability in the core layer 1. Compared with the situation without a cross-linking agent, the cross-linked core layer 1 can better maintain its shape and structural integrity, preventing excessive swelling or shrinkage during the moisture absorption and release process. In addition, the formation of the cross-linked network affects the charge transport inside the core layer 1. On the one hand, it restricts the free movement path of charges, making the charges need to bypass the cross-linking points for transport; on the other hand, it also stabilizes the structure of the core layer 1, making the charge transport channels more fixed. This structural design can improve the directionality of charge transport, reduce charge scattering, and thus improve the power generation efficiency.

[0075] Performance test: Place the device in an environment with a humidity of 85% and connect it to a circuit with an external resistance of 60 Ω. The test results show that the voltage generated by this device is between 0.8 - 1.8 V, and after continuous operation for 120 hours, the performance can still be maintained above 90% of the initial performance, demonstrating good stability. This indicates that by adjusting the ratio of PVA and SA in the core layer 1 and introducing CaCl2 as a cross-linking agent, the fabricated power generation device exhibits good electrical output performance and stability in a high-humidity environment. This preparation method provides an effective way to improve the performance of moisture power generation devices and is expected to be applied in the field of sustainable energy. By optimizing the material composition and cross-linking strategy, the efficiency and service life of the device can be further improved.

[0076] The working principle of the moisture power generation device involves the following key steps: 1. Moisture absorption: The highly water-absorbent materials used in the core layer 1, such as porous water-absorbent polymers, can efficiently absorb moisture from the surrounding environment. This process is the basis for the operation of the power generation device because the absorbed water is the raw material for generating electric energy.

[0077] 2. Charge generation: When the core layer 1 material absorbs moisture, charges will be generated due to changes in the chemical properties or physical structure of the material. The generation of these charges may result from the interaction between water molecules and the core layer 1 material. For example, hydration may lead to the redistribution of charges on the material surface.

[0078] 3. Charge conduction: The generated charges need to be effectively conducted to the external circuit. For this purpose, the shell layer 2 is composed of conductive materials, such as carbon-based materials or metal layers, whose function is to collect the charges generated by the core layer 1 and conduct them to the electrode 3.

[0079] 4. Electrical energy output: The charge is conducted through the shell layer 2 to the electrode 3. As a charge collector, the electrode 3 exports the charge and connects it to an external circuit. In this way, the moisture power generation device can convert the absorbed moisture into electrical energy for external devices to use.

[0080] Throughout the process, the collaborative work of the core layer 1 and the shell layer 2 is the key to achieving efficient moisture power generation. The core layer 1 is responsible for absorbing moisture and generating charges, while the shell layer 2 is responsible for quickly conducting these charges to the electrode 3 to ensure the effective output of electrical energy. The design of this device allows the direct conversion of ambient moisture into electrical energy, providing new possibilities for the development of clean energy.

[0081] The beneficial effects of the present invention are as follows: 1. Efficient utilization of moisture: The highly water-absorbent material of the core layer 1 can efficiently absorb moisture in the environment, improving the utilization rate of moisture and thus enhancing the power generation efficiency. Specifically, the efficient utilization of moisture is reflected in the following aspects: (1) Moisture capture mechanism The highly water-absorbent material of the core layer 1, such as the porous water-absorbent polymer made of polyvinyl alcohol (PVA) and polyacrylic acid (PAA), has a unique molecular structure and microscopic pore structure. This structure enables the material to form various interactions with water molecules in moisture at the molecular level, such as hydrogen bonds and van der Waals forces. From a macroscopic perspective, it is like a precise "moisture filter screen" that can efficiently capture moisture molecules in the environment. Whether the environmental humidity is at a relatively low level or a high humidity environment, it can continuously absorb moisture, thus greatly improving the moisture collection efficiency.

[0082] (2) Principle of improving power generation efficiency In the process of moisture power generation, moisture is the key element of energy conversion. More moisture being absorbed means more water molecules participating in the interaction with the material of the core layer 1. This interaction will trigger a series of complex physical and chemical processes, such as ion dissociation, migration, and charge generation. Due to more moisture participating, these processes can proceed more fully, resulting in the generation of more charges and ultimately achieving a significant improvement in power generation efficiency. Compared with traditional power generation methods, the moisture power generation device does not need to rely on specific energy resources, such as fossil fuels or large-scale water conservancy facilities. It can make full use of the moisture that is ubiquitous in the environment and is an innovative way to more efficiently utilize energy resources.

[0083] 2. Stability and durability: The special design of the shell layer 2 not only ensures the effective utilization of moisture but also can effectively conduct the generated charges. At the same time, it has a certain degree of waterproofness, effectively improving the stability and durability of the device, making the performance of the device not easily decline during long-term use.

[0084] Specifically, the stability and durability are reflected in the multi-functional design of the shell layer 2, which is composed of a conductive and somewhat waterproof material such as a graphene composite film, and it plays a key role in multiple aspects in the moisture power generation device.

[0085] First of all, in terms of water utilization, the structural design of the shell layer 2 can precisely control the entry and exit of water. Its pore structure allows moisture to smoothly enter the core layer 1 for absorption and utilization, while preventing excessive or rapid water loss, ensuring the continuous and effective utilization of water throughout the power generation process.

[0086] Secondly, in terms of charge conduction, the graphene composite film has excellent electrical conductivity. When the core layer 1 material generates charges after interacting with moisture, the shell layer 2 can quickly and efficiently conduct these charges out, just like an unobstructed "charge highway", avoiding the accumulation of charges inside the device, thus ensuring the stable progress of the power generation process.

[0087] Furthermore, the waterproof property of the shell layer 2 is an important guarantee for its durability. In actual use scenarios, the device may be exposed to various complex environmental conditions and may come into contact with liquid water or a large amount of water vapor in a high-humidity environment. The waterproof property of the shell layer 2 can effectively prevent the intrusion of liquid water, preventing damage to internal components such as the core layer 1 material and the electrode 3, thus ensuring the stable performance of the device during long-term use and being less likely to experience performance degradation. This stability and durability make the moisture power generation device more competitive in long-term energy supply scenarios. Compared with other traditional power generation devices, it can reduce maintenance costs and replacement frequencies.

[0088] 3. Simple preparation method: Through the preparation method provided by the present invention, the structure and performance of the device can be precisely controlled, and the preparation process is relatively simple, without the need for complex equipment and processes, and is easy to realize industrial large-scale production, having good application prospects. The simplicity of the preparation method is reflected in the following aspects: (1) Precise control of structure and performance The preparation method provided by the present invention has unique advantages and can precisely control the structure and performance of the moisture power generation device. During the preparation process of the core layer 1, by adjusting the ratio of polyvinyl alcohol (PVA) and polyacrylic acid (PAA), the performance parameters such as the porosity and water absorption of the porous water-absorbing polymer can be flexibly changed. For example, different ratios can make the core layer 1 material vary in terms of the speed and capacity of absorbing moisture, so as to adapt to different environmental humidity conditions.

[0089] During the preparation of the shell layer 2, by changing factors such as the concentration of graphene in the graphene dispersion, the type and dosage of the polymer binder, etc., the electrical conductivity, waterproof performance, and the bonding strength with the core layer 1 of the shell layer 2 can be precisely regulated. This precise control enables the moisture power generation device to be customized according to different application requirements. Whether it is a small portable electronic device or a large distributed energy supply system, it can meet their special requirements for the structure and performance of the power generation device.

[0090] (2)Industrial large-scale production potential The entire preparation process is relatively simple and does not require complex equipment and high-end process technologies. In the preparation of the core layer 1, after simply mixing and stirring the raw materials, the required porous structure material can be obtained using a conventional freeze-thaw cycle device. In the preparation process of the shell layer 2, common organic solvents (such as N-methylpyrrolidone), polymer binders (such as polyvinylidene fluoride), and the solution casting method are all materials and methods commonly used in the chemical industry. Although the physical vapor deposition method used for the installation of the electrode 3 is a relatively advanced technology, it has been quite mature in industrial production, and the control of the deposition thickness between 100 - 500 nm is also relatively easy to achieve. This simple and feasible preparation method means lower production costs, shorter production cycles, and higher production efficiency, which is very conducive to realizing industrial large-scale production. This can not only meet the growing market demand for moisture power generation devices but also promote the wide application of moisture power generation technology in the energy field and provide strong support for the development of sustainable energy.

[0091] 4. Environmentally friendly and sustainable: Moisture power generation is a clean energy conversion technology that does not produce pollutants and greenhouse gas emissions. It utilizes the moisture in the air, which is a renewable energy source and helps to achieve the sustainable development goals.

[0092] 5. Wide application range: Moisture power generation devices can be applied to a variety of scenarios, including but not limited to self-powered electronic devices, wearable devices, Internet of Things devices, etc. The flexibility and scalability of this technology give it broad application prospects.

[0093] 6. Improve energy utilization efficiency: Moisture power generation devices can convert the originally neglected moisture energy into electrical energy, improving the energy utilization efficiency. This is of great significance for alleviating the energy crisis and enhancing energy security.

[0094] In the description of the present application, it should be noted that the orientation or positional relationship indicated by terms such as "upper" and "lower" is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation to the present application. Unless otherwise clearly specified and defined, the terms "mounted", "connected" and "coupled" should be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or an integral connection; it may be a mechanical connection, or an electrical connection; it may be directly connected, or indirectly connected through an intermediate medium, and it may be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to specific circumstances.

[0095] It should be noted that in the present application, relational terms such as "first" and "second" are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "comprising", "including" or any other variation thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements not only includes those elements, but also includes other elements not expressly listed, or also includes elements inherent to such process, method, article or device. Without further limitation, an element defined by the statement "comprising a..." does not exclude the existence of additional identical elements in the process, method, article or device including the said element.

[0096] The specific embodiments of the present invention described above do not constitute a limitation to the protection scope of the present invention. Any corresponding changes and modifications made according to the technical concept of the present invention should be included in the protection scope of the claims of the present invention.

Claims

1. A wet gas power generation device, characterized in that: include: a core layer, the core layer being made of a water-absorbing material for absorbing moisture and generating electric charges through the interaction of moisture with ions in the core layer; A shell layer, which is wrapped around the core layer and is made of a conductive and waterproof material and is used to conduct the charge generated by the core layer; as well as, At least two groups of electrodes are disposed on both sides of the shell layer, respectively, and connected to the shell layer, for conducting the charges conducted by the shell layer.

2. The wet gas power generation device according to claim 1, characterized in that: The water-absorbing material of the core layer is a porous water-absorbing polymer.

3. The wet gas power generation device according to claim 1, characterized in that: The shell layer is a composite film prepared from a conductive agent, wherein the conductive agent is at least one of pyrrole, carbon nanotube powder, graphene, carbon nanotube, Mxene, superconducting carbon black, and acetylene black.

4. The wet gas power generation device according to claim 1, characterized in that: The electrodes are made of metal material.

5. A method for preparing a wet gas power generation device, characterized in that: The method for preparing the wet gas power generation device according to any one of claims 1 to 4 comprises the following steps: S1: mixing the raw materials of the porous water-absorbing polymer in deionized water, forming a porous structure through a freeze-thaw cycle, and obtaining the core layer; S2: dispersing the conductive agent in an organic solvent, adding a polymer binder, stirring evenly, casting the solution on the surface of the core layer using a solution casting method and drying; S3: Electrodes are deposited on both sides of the shell layer using physical vapor deposition.

6. The method for preparing a wet gas power generation device according to claim 5, characterized in that: In step S1, the porous water-absorbing polymer is made of one of polyvinyl alcohol, polyacrylic acid, polyaniline, and sodium alginate, or a combination of more than one of them.

7. The method for preparing a wet gas power generation device according to claim 5, characterized in that: In step S2, zinc oxide is further added to the organic solvent in a mass ratio of 0-2:100 to the polymer binder, and the mass ratio of the polymer binder to the conductive agent is 10-100:

1.

8. The method for preparing a wet gas power generation device according to claim 5, characterized in that: In step S2, the organic solvent is at least one of N-methylpyrrolidone, N,N-dimethylformamide, N,N-dimethylacetamide, and acetone, the polymer binder is polyvinylidene fluoride, and the mass fraction of the polymer binder is 5%-15% of the organic solvent.

9. The method for preparing a wet gas power generation device according to claim 5, characterized in that: In step S3, the electrode is a silver or copper electrode, and its deposition thickness is between 100-500 nm.

10. Use of the wet gas power generation device according to any one of claims 1 to 4 in power generation.

Images