Conductor-ionic membrane and electrodeless salinity difference power generation device manufactured by using conductor-ionic membrane
By introducing a three-dimensional network structure conductor material into the ion exchange membrane, the direct conversion of ion current to electron current is achieved by utilizing the Coulomb drag effect, which solves the problems of energy loss and system instability caused by electrode redox reactions and provides an efficient electrodeless salinity gradient power generation solution.
Patent Information
- Application Number
- CN202511059339.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-07-30
- Publication Date
- 2025-11-21
AI Technical Summary
In existing salinity gradient power generation devices, the redox reaction of the electrodes leads to energy loss and system instability, making it difficult to achieve continuous operation of the electrodes. Furthermore, existing technologies have failed to effectively utilize conductor-ion membranes for the direct conversion of ionic current to electronic current.
The conductor-ion membrane employs a three-dimensional network structure, utilizing conductive materials such as graphene and carbon nanotubes to form a continuous conductive network within the ion membrane. Through the Coulomb drag effect, ions drive electron migration during diffusion, thus eliminating the need for electrodes.
It achieves electrodeless salt gradient power generation, improves energy conversion efficiency and current transmission efficiency, avoids energy loss and system instability caused by electrode reactions, and simplifies the device structure.
Smart Images
Figure CN120990835A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of renewable energy, and in particular to a conductor-ion membrane and an electrodeless salinity gradient power generation device made using the conductor-ion membrane. Background Technology
[0002] The global energy crisis, climate change, and irreversible environmental pollution caused by the pursuit of energy have severely impacted human development. Therefore, people have been exploring renewable, clean, and green energy sources to replace high-emission and non-renewable fossil fuels. Ocean energy has come into the public eye against this backdrop. Ocean energy encompasses a variety of energy forms, with tidal energy, wave energy, ocean current energy, ocean thermal energy conversion (OTEC), and ocean salinity gradient energy being the main areas of research. According to entropy change estimates, each ton of seawater / freshwater (river water) mixture can release 0.8 kWh of salinity gradient energy. For example, the Amazon River alone can reach 1 TW (10¹² watts) of power. Because salinity gradient energy is concentrated at river mouths, it has high energy density and is easy to collect, making it a promising area. Currently, three methods for extracting permeable energy are widely studied: pressure-delayed permeation (PRO), reverse electrodialysis (RED), and chemical power source mixing technology (Accmix). However, current challenges include high equipment investment and maintenance costs, and low energy efficiency of the equipment.
[0003] With breakthroughs in membrane materials science and nanotechnology, ion exchange membranes (REDs) have made significant progress in energy conversion efficiency, system stability, and cost control. REDs place ion-selective permeable membranes between salt solutions of varying concentrations. Utilizing the concentration difference between different ions, ions migrate directionally under the sieving of the ion exchange membrane, thereby converting chemical potential energy into electrical energy. The development of high-performance ion-selective membranes is crucial for collecting permeate energy, and achieving strong ion selectivity and high ion flux has become a current research focus. High-performance ion exchange membranes can also be combined with ion electronics for use in flexible electronic devices, powering implantable electronic devices in human-machine interfaces. Furthermore, the role of the electrode system in converting ion current into electron current through redox reactions cannot be ignored. In laboratory-scale RED systems, Ag / AgCl electrodes are widely used to measure their electrochemical performance. Energy losses caused by redox reactions at the electrodes are generally neglected. However, in practical applications, electrode reactions can affect scaling and fouling of the ion exchange membrane in the RED system, thus affecting electrochemical kinetics and increasing resistance. To reduce electrode resistance and improve thermal / chemical stability, metal oxides or noble metals are used in electrode modification, but their high overall cost limits their widespread adoption. Graphite composite electrodes have gained popularity due to their low cost and high-performance electrochemical properties, but they face challenges in practical applications, such as low mechanical durability and the need for frequent replacements. Electrodes play a crucial role in redox extraction of permeate energy, and ensuring continuous electrode operation is one of the key challenges for large-scale application of RED systems. Three solutions exist: first, periodic mechanical electrode swapping, which is complex and uneconomical in practice; second, periodic feed water swapping combined with membrane surface cleaning techniques to alter the current direction and ensure continuous electrode operation, but this leads to colloidal fouling and scaling on the membrane surface, increasing the device's internal resistance; third, using an asymmetric electrode layout, which increases concentration polarization, reducing overall power and potentially causing side reactions such as the formation of chlorate (ClO3). ⁻ ) and hypochlorite (ClO - ).
[0004] The dragging effect of ions has been observed in nanofluidic devices, extending the concept of Coulomb drag to the interaction between moving ion fluids and electrons in conductors; or utilizing the amplified current generated by the Coulomb drag effect to solve the low-current bottleneck in the practical application of nanoenergy generators. Furthermore, Jiang et al. developed a nanofluidized electric generator (NCEG) composed of a carbon nanotube membrane (CNTM) sandwiched between metal electrodes, where a spontaneous redox reaction between the metal and oxygen in the electrolyte solution allows ions to move within the carbon nanotubes. Through the Coulomb dragging effect between the moving ions in these nanotubes and electrons in the CNTM, a current of 1.2 mA / cm² was generated. 2 The amplified current is 16 times higher than the current collected without CNTM.
[0005] The concept of ion-electron coupling transport has been applied to amplify current in flexible sensors and nanofluidic devices. Ion-electron coupling transport is thought to generate current through the Coulomb drag effect under the influence of spontaneous ion flow. Based on this, it is possible to break the dependence of traditional salinity gradient power generation on electrodes, and directly convert ion current into electron current by utilizing the ion selectivity and conductivity of the conductor-ion membrane. However, the direct application of the theory of ion-electron coupling transport to ion membranes and overcoming the dependence of extraction permeation energy on electrodes has not been reported. Summary of the Invention
[0006] To address the challenge of maintaining continuous electrode operation in current salinity gradient electrode power generation devices, this invention provides a conductor-ion membrane and an electrodeless salinity gradient power generation device made using the conductor-ion membrane.
[0007] The specific technical solution of the present invention is as follows: A conductor-ion membrane for an electrodeless salinity gradient power generation device includes an ion membrane with a three-dimensional mesh structure of conductors inside, allowing electrons in the ion membrane to be transferred through the conductors inside the ion membrane.
[0008] The ion exchange membrane is a biopolymer membrane or a graphene oxide membrane.
[0009] The biopolymer membrane is made of sodium alginate and chitosan oligosaccharide; the graphene oxide membrane is made of graphene oxide; and the conductor is made of graphene, carbon nanotubes, or metal nanowires.
[0010] The conductor accounts for 0.1%-10% of the mass of the ion exchange membrane, and the conductor diameter ranges from 1 to 100 nm.
[0011] The method for preparing the conductor-ion membrane includes the following steps: (1) Weigh a certain amount of chitosan oligosaccharide powder, add it to deionized water to form a first solution, stir for 4 hours to fully dissolve it, and let it stand to remove bubbles, so that the mass ratio of chitosan oligosaccharide powder in the first solution is 30%-40%; (2) Weigh a certain amount of sodium alginate powder, add it to deionized water to form a second solution, stir for 4 h, then heat it to 50℃ and continue stirring for 0.5 h to fully dissolve it, so that the mass ratio of sodium alginate powder in the first solution is 1%-2%; (3) Weigh 3g of single-layer graphene and 3g of single-walled carbon nanotubes and add them to the second solution. Sonicate for 1 hour to form a uniform suspension, so that the total mass of single-layer graphene and single-walled carbon nanotubes accounts for 3% of the weight of the suspension. (4) Pour the prepared first solution into a plastic petri dish and let it stand to defoam. After defoaming, quickly immerse it in the suspension prepared in step (3). The first solution and the suspension prepared in step (3) react at the interface and form a film after 1 minute of reaction. (5) Take out the membrane formed in step (4) and rinse it with deionized water to obtain a conductor-ion membrane.
[0012] The method for preparing the conductor-ion membrane includes the following steps: (1) Dilute the graphene oxide dispersion with N-methylpyrrolidone to obtain a 10 mg / mL graphene oxide dispersion; then take 0-5 g of graphene dispersion and add it dropwise to the 10 mg / mL graphene oxide dispersion, and ultrasonically disperse for 1 h to obtain a uniform graphene oxide-graphene dispersion. (2) The graphene oxide-graphene dispersion obtained in step (1) is filtered through a polytetrafluoroethylene membrane by vacuum method to obtain a wet conductor-ion membrane with a thickness of 0.5-1 mm. (3) The wet conductor-ion membrane was dried at room temperature for 48 hours and then peeled off from the surface of the polytetrafluoroethylene membrane to obtain the dried conductor-ion membrane.
[0013] An electrodeless salinity gradient power generation device using a conductor-ion membrane is disclosed. The device includes a solution pool and a membrane plate. The membrane plate is disposed inside the solution pool, forming two independent chambers. The two independent chambers are respectively filled with a concentrated salt solution and a dilute salt solution. A conductor-ion membrane is disposed between the two membrane plates, and the conductor-ion membrane is in direct contact with the solutions in the two chambers. The side of the conductor-ion membrane in contact with the concentrated salt solution forms the positive electrode, and the side of the conductor-ion membrane in contact with the dilute salt solution forms the negative electrode. The positive and negative electrodes are connected to an external circuit via wires.
[0014] An electrodeless salinity gradient power generation device made using a conductor-ion membrane is disclosed. The device includes at least one capsule-shaped conductor-ion membrane placed in a solution pool. An opening is provided at the top of the capsule-shaped conductor-ion membrane. A concentrated salt solution is placed inside the capsule-shaped conductor-ion membrane, and a low-salt solution is placed in the solution pool outside the capsule-shaped conductor-ion membrane. The side of the capsule-shaped conductor-ion membrane in contact with the concentrated salt solution forms a positive electrode, and the side of the capsule-shaped conductor-ion membrane in contact with the dilute salt solution forms a negative electrode. The positive and negative electrodes are connected to an external circuit via wires.
[0015] An electrodeless salinity gradient power generation device made using a conductor-ion membrane is provided. The electrodeless salinity gradient power generation device includes at least one tubular conductor-ion membrane placed in a closed container. The two ends of the tubular conductor-ion membrane are insulated from the outside of the closed container to form a first liquid inlet and a first liquid outlet. The closed container is provided with a second liquid inlet and a second liquid outlet. The inner and outer walls of the tubular conductor-ion membrane are respectively connected to an external circuit.
[0016] The molar concentration ratio of the concentrated salt solution to the dilute salt solution is 0.001M-0.5M.
[0017] Compared with the prior art, the beneficial effects of the present invention are: 1. This invention simplifies the salinity gradient power generation device. In the process of extracting osmotic energy, there is no need for the redox steps of the electrodes. By adding a conductor during the preparation of the ion membrane, a conductor-ion membrane is obtained. Since the conductor itself has a large number of freely moving electrons, when the conductor is doped into the ion membrane, these conductor particles or conductive phases can be interconnected or form a continuous three-dimensional conductive network inside the conductor-ion membrane, thereby generating a stable current.
[0018] 2. Electrodeless salinity gradient power generation device using conductor-ion membrane. This device utilizes the principle of diffusion and Coulomb force to enable electrons inside the conductor-ion membrane to migrate under the influence of Coulomb force during ion diffusion. Electron accumulation forms on the conductor-ion membrane side of the dilute solution. When a certain number of electrons accumulate, they move towards the external circuit, forming a current. After circulating through the external circuit, the current returns to the conductor-ion membrane side of the concentrated solution. This theoretical method is applicable to various ions or ion clusters, and there are no issues related to potential adaptation, material consumption, or volume changes. Furthermore, the electrodeless salinity gradient power generation device using conductor-ion membrane has higher efficiency in electron transfer and energy conversion.
[0019] 3. The salinity gradient power generation device provided by this invention allows ions to transfer from a high concentration region to a low concentration region until... Evenly distributed clothDuring the diffusion process, the moving ions attract internal electrons at the conductor-ion membrane interface and bind to them, thereby realizing the transfer of electrons by ions and the conversion of current. This process does not require electrodes and avoids some unavoidable side reactions that occur at the cathode and anode during the oxygen reduction reaction in the salt gradient power generation process, which can lead to energy loss and system instability. Attached Figure Description
[0020] Figure 1 This is a schematic diagram of the electrodeless salinity gradient power generation device according to Embodiment 1 of the present invention.
[0021] Figure 2 This is a schematic diagram of the structure of the membrane plate in Embodiment 1 of the present invention.
[0022] Figure 3 This is a comparison chart showing the voltage and current generated by an ion-exchange membrane prepared without carbon nanotubes in this invention used in an electrode-salt gradient power generation device, and a conductor-ion-exchange membrane prepared with carbon nanotubes used in an electrodeless salinity gradient power generation device.
[0023] Figure 4 This is a physical image of the electrodeless salinity gradient power generation device according to Embodiment 1 of the present invention.
[0024] Wherein, 1 is the solution pool; 2 is the membrane plate; 3 is the conductor-ion membrane; 21 is groove I; and 22 is groove II. Detailed Implementation
[0025] The present invention will be further described below through specific embodiments, but the implementation of the present invention is not limited thereto. Other examples obtained by those skilled in the art without creative effort are all within the scope of protection of this application.
[0026] A method for preparing a conductor-ion membrane, using chitosan oligosaccharide-sodium alginate as the substrate membrane, specifically includes the following steps: (1) Weigh a certain amount of chitosan oligosaccharide powder, add it to deionized water to form a first solution, stir for 4 hours to fully dissolve it, and let it stand to remove bubbles, so that the mass ratio of chitosan oligosaccharide powder in the first solution is 30%-40%; (2) Weigh a certain amount of sodium alginate powder, add it to deionized water to form a second solution, stir for 4 h, then heat it to 50℃ and continue stirring for 0.5 h to fully dissolve it, so that the mass ratio of sodium alginate powder in the first solution is 1%-2%; (3) Weigh 3g of single-layer graphene and 3g of single-walled carbon nanotubes and add them to the second solution. Sonicate for 1 hour to form a uniform suspension, so that the total mass of single-layer graphene and single-walled carbon nanotubes accounts for 3% of the weight of the suspension. (4) Pour the prepared first solution into a plastic petri dish and let it stand to defoam. After defoaming, quickly immerse it in the suspension prepared in step (3). The first solution and the suspension prepared in step (3) react at the interface and form a film after 1 minute of reaction. (5) Take out the membrane formed in step (4) and rinse it with deionized water to obtain a conductor-ion membrane.
[0027] This invention provides a method for preparing a conductor-ion membrane, using chitosan oligosaccharide-sodium alginate as the substrate membrane. Sodium alginate and chitosan oligosaccharide can be bonded together via hydrogen bonding and electrostatic interactions to form the membrane. Chitosan oligosaccharide dissolves in water to form -NH3. + Therefore, more conductors can be anchored through electrostatic interaction. The negative charge on the surface of the conductor will attract cations to pass through. The conductor-ion membrane has cation selectivity, so it will attract more cations to transport across the membrane, which will allow more electrons to be transferred.
[0028] A method for preparing a conductor-ion membrane, using graphene oxide as the substrate membrane, specifically includes the following steps: (1) Dilute the graphene oxide dispersion with N-methylpyrrolidone to obtain a 10 mg / mL graphene oxide dispersion; then take 0-5 g of graphene dispersion and add it dropwise to the 10 mg / mL graphene oxide dispersion, and ultrasonically disperse for 1 h to obtain a uniform graphene oxide-graphene dispersion. (2) The graphene oxide-graphene dispersion obtained in step (1) is filtered through a polytetrafluoroethylene membrane by vacuum method to obtain a wet conductor-ion membrane with a thickness of 0.5-1 mm. (3) The wet conductor-ion membrane was dried at room temperature for 48 hours and then peeled off from the surface of the polytetrafluoroethylene membrane to obtain the dried conductor-ion membrane.
[0029] This invention provides a method for preparing a conductor-ion membrane using graphene oxide as the substrate. Graphene oxide and graphene oxide can interact through π-π stacking (non-covalent interaction), supplemented by a small number of covalent bonds, forming a dual effect of non-covalent and covalent bonding, thus improving the mechanical properties of the conductor-ion membrane. The surface of graphene oxide is rich in hydroxyl (-OH) and carboxyl (-COOH) groups, giving the conductor-ion membrane a large number of negatively charged groups. The conductor-ion membrane is selective for cations, thus attracting more cations for transmembrane transport, resulting in the transfer of more electrons.
[0030] To prevent the conductor-ion membrane from drying out, the prepared conductor-ion membrane is immersed in ultrapure water for subsequent use.
[0031] The conductor-ion membrane prepared by this invention has a large number of freely moving electrons. When conductors are doped into the ion membrane, these conductor particles or conductive phases can connect with each other or form a continuous three-dimensional conductive network inside the conductor-ion membrane, thereby generating a stable current.
[0032] The conductor-ion membrane includes an ion membrane, wherein a three-dimensional mesh structure of conductors is disposed inside the ion membrane, so that electrons in the ion membrane are transferred through the conductors inside the ion membrane.
[0033] Ion exchange membranes are ion-selective membranes, and they can be biopolymer membranes or graphene oxide membranes.
[0034] The materials for the biopolymer membrane are selected from sodium alginate and chitosan oligosaccharide.
[0035] The material of the graphene oxide film is selected from graphene oxide; the conductor material is selected from graphene, or carbon nanotubes, or metal nanoparticles, with a conductor diameter ranging from 1 to 100 nm.
[0036] To ensure the continuity of the electron migration network, the conductor mass accounts for 0.1%-10% of the ion-exchange membrane, and the conductor diameter ranges from 1 to 100 nm.
[0037] An electrodeless salinity gradient power generation device using a conductor-ion membrane is further described below through specific embodiments. However, these embodiments are merely exemplary and do not constitute any limitation on the scope of protection of this invention.
[0038] Example 1 like Figure 1-2 As shown, an electrodeless salinity gradient power generation device made using a conductor-ion membrane is disclosed. The electrodeless salinity gradient power generation device includes a solution pool 1 and a membrane plate 2. The membrane plate 2 is disposed inside the solution pool 1, so that the solution pool 1 forms two independent chambers. The two independent chambers are respectively filled with a concentrated salt solution and a dilute salt solution. A conductor-ion membrane 3 is disposed between the two membrane plates 2. The conductor-ion membrane 3 is in direct contact with the solutions in the two chambers. The side of the conductor-ion membrane 3 in contact with the concentrated salt solution forms the positive electrode, and the side of the conductor-ion membrane 3 in contact with the dilute salt solution forms the negative electrode. The positive and negative electrodes are connected to an external circuit through wires.
[0039] Furthermore, the membrane plate 2 is provided with a groove I 21, and a groove II 22 is provided inside the groove I 21. Carbon cloth or copper sheet is placed in the groove I 21 to connect the wires. The groove II 22 is connected to a voltmeter, an ammeter, or other equipment through the wires to test the electrochemical data of the electrodeless salt gradient power generation device. The current is drawn out through the carbon cloth or copper sheet placed in the groove I and connected to the outside through the wires. The carbon cloth or copper sheet acts as a current collector, which can conduct electricity more uniformly, reduce losses, adapt to the device structure, and withstand the electrochemical environment, significantly improving the performance and stability of the device.
[0040] Example 2 An electrodeless salinity gradient power generation device using a conductor-ion membrane is disclosed. The device comprises at least one capsule-shaped conductor-ion membrane placed in a solution pool. An opening is provided at the top of the capsule-shaped conductor-ion membrane. A concentrated salt solution is placed inside the capsule-shaped conductor-ion membrane, while a low-salt solution is placed in the solution pool outside the capsule-shaped conductor-ion membrane. The side of the capsule-shaped conductor-ion membrane in contact with the concentrated salt solution forms a positive electrode, and the side in contact with the dilute salt solution forms a negative electrode. The positive and negative electrodes are connected to an external circuit via wires. Optimizing the conductor-ion membrane into a capsule shape effectively increases the contact area, facilitating ion diffusion. Simultaneously, the concentrated salt solution inside the capsule-shaped conductor-ion membrane reduces its dispersion in space, continuously maintaining the concentration difference across the membrane.
[0041] The capsule-shaped conductor-ion membrane can be spherical, elliptical, or disc-shaped.
[0042] Example 3 An electrodeless salinity gradient power generation device using a conductor-ion membrane is disclosed. The device comprises at least one tubular conductor-ion membrane placed in a closed container. The two ends of the tubular conductor-ion membrane are insulated from the outside of the closed container, forming a first inlet and a first outlet. The closed container has a second inlet and a second outlet. The inner and outer walls of the tubular conductor-ion membrane are connected to an external circuit. The tubular conductor-ion membrane can be connected in series or in parallel, similar to the structure of a heat exchanger. This invention provides an electrodeless salinity gradient power generation device using a tubular conductor-ion membrane. The two ends of the tubular conductor-ion membrane are connected to the outside of the closed container, forming a first inlet and a first outlet. The closed container has a second inlet and a second outlet. A continuous supply of salt solution is provided through the inlet, and a diluted salt solution flows out through the outlet, maintaining the concentration difference between the inside of the tubular conductor-ion membrane and the outside of the closed container, thereby providing a stable current and ensuring circuit stability.
[0043] According to a preferred embodiment of the present invention, the molar concentration ratio of the concentrated salt solution to the dilute salt solution is 0.001M-0.5M.
[0044] In a further preferred embodiment, the molar concentration of the concentrated salt solution is 500 times that of the dilute salt solution.
[0045] According to a preferred embodiment of the present invention, the electrodeless salinity gradient power generation device is printed with an identical electrodeless salinity gradient power generation device using a 3D printer. The external circuit of the electrodeless salinity gradient power generation device can be connected in parallel or in series; series connection is used to increase voltage, and parallel connection is used to increase current.
[0046] The following describes, with reference to specific embodiment 1, the process of generating current using an electrodeless salinity gradient power generation device made of a conductor-ion membrane.
[0047] First, a 0.01mm thick copper sheet is fixed in groove I of the clamping plate and connected with wires. Groove II is connected to a digital source meter via wires. A conductor-ion membrane with chitosan oligosaccharide-sodium alginate as the base membrane is selected and placed between the two clamping plates. This membrane is then inserted into the solution pool, creating two independent chambers. 0.001mol / L KCl solution and 0.5mol / L KCl solution are added to the two chambers respectively. Due to the difference in ion concentration on both sides of the conductor-ion membrane, this concentration imbalance generates a chemical potential difference, driving ions to diffuse from the high-concentration solution side to the low-concentration solution side. Therefore, KCl... + Diffusion from high-salt solution to high-salt solution involves cations diffusing and attracting electrons (holes) inside the ion exchange membrane under the influence of Coulomb force. The movement of electrons is reflected as an electric current on the conductor-ion exchange membrane. The current is transmitted to the copper plate, and the generated current and voltage can be recorded on a digital source meter. At the instant KCl solution is added to the solution pool, the voltage and current will change abruptly, proving the feasibility of the "ion transport electron" theory.
[0048] Then, conductor-ion membranes with conductor concentrations of 0%, 1.3%, 2.3%, and 3.3% were used in an electrodeless salinity gradient power generation device to detect whether the device generated current and voltage. The results showed that when the conductor-ion membrane with a conductor concentration of 0% was used in the electrodeless salinity gradient power generation device, no current or voltage was detected.
[0049] The reason is that in electrode-salt gradient power generation, electrons themselves cannot directly migrate within the ion-exchange membrane; it is ions that actually migrate. However, electrons participate in the entire charge transfer process through electrodes and external circuits, thereby generating current. In an ion-exchange membrane doped with a conductor, cations, under the influence of Coulomb forces, drive electrons in the conductor within the membrane to move within the membrane, forming an electron accumulation on the dilute salt solution side. Once a certain number of electrons accumulate, they move towards the external circuit, generating current, and return to the concentrated salt solution conductor-ion-exchange membrane side. This allows electrons to migrate and generate current on the conductor-ion-exchange membrane, eliminating the need for electrodes in the concentrated and dilute salt solution chambers to form a complete circuit.
[0050] Finally, an ion-exchange membrane prepared without carbon nanotubes was used in an electrode-salt gradient power generation device, and a conductor-ion-exchange membrane prepared with carbon nanotubes was used in an electrodeless salinity gradient power generation device. The current and voltage generated by the devices were detected. Figure 3 As shown, the conductor-ion membrane prepared with carbon nanotubes exhibits conductivity in electrodeless salinity gradient power generation devices. Furthermore, the short-circuit current and open-circuit voltage generated by the conductor-ion membrane prepared with carbon nanotubes in electrodeless salinity gradient power generation devices are higher than those generated by the ion membrane prepared without carbon nanotubes in electrode-salinity gradient power generation devices. This demonstrates that the electrodeless salinity gradient power generation devices made with conductor-ion membranes have higher electron transfer efficiency and energy conversion efficiency.
[0051] In summary, this invention provides a conductor-ion membrane and an electrodeless salinity gradient power generation device made using the conductor-ion membrane: (1) By adding a conductor during the preparation of the ion membrane, a conductor-ion membrane is obtained. Since the conductor itself has a large number of freely moving electrons, when the conductor is doped into the ion membrane, these conductor particles or conductive phases can be connected to each other or form a continuous conductive network inside the conductor-ion membrane, thereby generating a stable current.
[0052] (2) Electrodeless salinity gradient power generation device made using conductor-ion membrane. Electrodeless salinity gradient power generation device utilizes the principle of diffusion phenomenon and Coulomb force to realize that ions migrate electrons inside the conductor-ion membrane under the action of Coulomb force during diffusion. Electron accumulation is formed on the conductor-ion membrane side of dilute solution. When a certain number of electrons accumulate, they will move towards the external circuit to form current. After circulating through the external circuit, they return to the conductor-ion membrane side of concentrated solution. This theoretical method is applicable to all kinds of ions or ion groups. There are no problems of potential adaptation, material consumption and volume change. Moreover, the electrodeless salinity gradient power generation device made of conductor-ion membrane has higher efficiency in electron transfer and energy conversion.
[0053] (3) In the salt gradient power generation device provided by the present invention, during the diffusion process of ions from high concentration area to low concentration area until uniform distribution, the moving ions are attracted to the internal electrons at the conductor-ion membrane interface to bind and move, thereby realizing the ion transfer of electrons and the process of current conversion. No electrodes are required, avoiding some unavoidable side reactions generated by the cathode and anode in the oxygen reduction reaction during the salt gradient power generation process, which leads to energy loss and system instability.
[0054] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the present invention. Various changes and modifications can be made to the present invention without departing from its spirit and scope. All such changes and modifications fall within the scope of the present invention as claimed, which is defined by the appended claims and their equivalents.
Claims
1. A conductor-ion membrane for an electrodeless salinity gradient power generation device, comprising an ion membrane, characterized in that, The ion membrane is equipped with a three-dimensional mesh structure of conductors, which allows electrons in the ion membrane to be transferred through the conductors inside the ion membrane.
2. The conductor-ion membrane for an electrodeless salinity gradient power generation device as described in claim 1, characterized in that, The ion exchange membrane is a biopolymer membrane or a graphene oxide membrane.
3. The conductor-ion membrane for an electrodeless salt gradient power generation device as described in claim 2, characterized in that, The biopolymer membrane is made of sodium alginate and chitosan oligosaccharide; the graphene oxide membrane is made of graphene oxide; and the conductor is made of graphene, carbon nanotubes, or metal nanowires.
4. The conductor-ion membrane for an electrodeless salinity gradient power generation device as described in claim 3, characterized in that, The conductor accounts for 0.1%-10% of the mass of the ion exchange membrane, and the conductor diameter ranges from 1 to 100 nm.
5. A conductor-ion membrane for an electrodeless salinity gradient power generation device as described in any one of claims 1-4, characterized in that, The method for preparing the conductor-ion membrane includes the following steps: (1) Weigh a certain amount of chitosan oligosaccharide powder, add it to deionized water to form a first solution, stir for 4 hours to fully dissolve it, and let it stand to remove bubbles, so that the mass ratio of chitosan oligosaccharide powder in the first solution is 30%-40%; (2) Weigh a certain amount of sodium alginate powder, add it to deionized water to form a second solution, stir for 4 hours, then heat it to 50°C and continue stirring for 0.5 hours to fully dissolve it, so that the mass ratio of sodium alginate powder in the first solution is 1%-2%; (3) Weigh 3g of single-layer graphene and 3g of single-walled carbon nanotubes and add them to the second solution. Sonicate for 1 hour to form a uniform suspension, so that the total mass of single-layer graphene and single-walled carbon nanotubes accounts for 3% of the weight of the suspension. (4) Pour the prepared first solution into a plastic petri dish and let it stand to defoam. After defoaming, quickly immerse it into the suspension prepared in step (3). The first solution and the suspension prepared in step (3) react at the interface and form a film after 1 minute of reaction. (5) Take out the membrane formed in step (4) and rinse it with deionized water to obtain a conductor-ion membrane.
6. A conductor-ion membrane for an electrodeless salinity gradient power generation device as described in any one of claims 1-4, characterized in that, The method for preparing the conductor-ion membrane includes the following steps: (1) Dilute the graphene oxide dispersion with N-methylpyrrolidone to obtain a 10 mg / mL graphene oxide dispersion; then take 0-5 g of graphene dispersion and add it dropwise to the 10 mg / mL graphene oxide dispersion, and ultrasonically disperse for 1 h to obtain a uniform graphene oxide-graphene dispersion. (2) The graphene oxide-graphene dispersion obtained in step (1) is filtered through a polytetrafluoroethylene membrane by vacuum method to obtain a wet conductor-ion membrane with a thickness of 0.5-1 mm. The wet conductor-ion membrane was dried at room temperature for 48 hours and then peeled off from the surface of the polytetrafluoroethylene membrane to obtain the dried conductor-ion membrane.
7. An electrodeless salinity gradient power generation device using a conductor-ion membrane, characterized in that, The electrodeless salinity gradient power generation device includes a solution tank and a membrane plate. The membrane plate is disposed inside the solution tank, so that the solution tank forms two independent chambers. The two independent chambers are respectively filled with concentrated salt solution and dilute salt solution. A conductor-ion membrane is disposed between the two membrane plates. The conductor-ion membrane is in direct contact with the solutions in the two chambers. The side of the conductor-ion membrane in contact with the concentrated salt solution forms the positive electrode, and the side of the conductor-ion membrane in contact with the dilute salt solution forms the negative electrode. The positive and negative electrodes are connected to an external circuit through wires.
8. An electrodeless salinity gradient power generation device made using a conductor-ion membrane, characterized in that, The electrodeless salinity gradient power generation device includes at least one capsule-shaped conductor-ion membrane placed in a solution pool. The capsule-shaped conductor-ion membrane has an opening at its top. A concentrated salt solution is placed inside the capsule-shaped conductor-ion membrane, and a low-salt solution is placed in the solution pool outside the capsule-shaped conductor-ion membrane. The side of the capsule-shaped conductor-ion membrane in contact with the concentrated salt solution forms a positive electrode, and the side of the capsule-shaped conductor-ion membrane in contact with the dilute salt solution forms a negative electrode. The positive and negative electrodes are connected to an external circuit through wires.
9. An electrodeless salinity gradient power generation device made using a conductor-ion membrane, characterized in that, The electrodeless salinity gradient power generation device includes at least one tubular conductor-ion membrane placed in a closed container. The two ends of the tubular conductor-ion membrane are insulated from the outside of the closed container to form a first liquid inlet and a first liquid outlet. The closed container is provided with a second liquid inlet and a second liquid outlet. The inner and outer walls of the tubular conductor-ion membrane are respectively connected to an external circuit.
10. A conductor-ion membrane-based electrodeless salinity gradient power generation device as described in any one of claims 7-9, characterized in that, The molar concentration ratio of the concentrated salt solution to the dilute salt solution is 0.001M-0.5M.