A porous monolayer graphene membrane, a preparation method thereof and application thereof in salinity power generation
By preparing porous monolayer graphene films using chemical vapor deposition and ozone etching, the problem of difficult pore size control was solved, enabling efficient conversion and large-scale production of salinity gradient energy power generation.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- HARBIN INST OF TECH
- Filing Date
- 2026-05-19
- Publication Date
- 2026-07-14
AI Technical Summary
The pore size of existing porous graphene membranes is difficult to control, resulting in low conversion efficiency of salinity gradient energy generation and hindering its large-scale development.
Porous monolayer graphene films were prepared by chemical vapor deposition and nanoporous structures were obtained by ozone etching. The etching conditions were controlled to achieve controllability of pore size and porosity.
The prepared porous monolayer graphene membrane has high porosity and ion selectivity, which improves the power density and energy conversion efficiency of the salt gradient power generation device and is suitable for large-scale production.
Smart Images
Figure CN122380355A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of graphene materials and new energy technology, specifically relating to a porous single-layer graphene membrane, its preparation method, and its application in salinity gradient power generation. Background Technology
[0002] Salinity gradient energy has the advantages of being renewable and providing stable 24-hour power supply. However, current salinity gradient energy generation technology has long been constrained by bottlenecks such as the inability to simultaneously achieve high flux and selectivity in traditional membrane materials, making it difficult to develop on a large scale.
[0003] Graphene is a type of graphene produced by sp 2 Two-dimensional materials composed of hybrid carbon atoms possess excellent mechanical properties and chemical stability, and are widely studied for applications in energy, sensing, and membrane separation. Due to its atomic-level thickness, monolayer graphene exhibits extremely low ion transport resistance, making it a promising candidate for salinity gradient power generation.
[0004] However, dense graphene films themselves lack ion permeability, requiring the introduction of nanopores to impart ion selectivity. Existing methods for preparing porous graphene mainly include wet etching, template methods, and laser etching. Wet etching is carried out in a liquid environment, making it difficult to control uniformity and easily resulting in irregular pore structures; template methods are complex and may introduce impurities or cause structural damage; laser etching is highly dependent on equipment, has a narrow process window, and is difficult to scale up.
[0005] Therefore, developing a simple, controllable, repeatable, and scalable method for preparing porous monolayer graphene is of great significance for improving the conversion efficiency of salinity gradient power generation. Summary of the Invention
[0006] The purpose of this invention is to solve the problems of difficult control of pore size and low salt gradient energy conversion efficiency in the prior art, and to provide a porous monolayer graphene film, its preparation method and its application in salt gradient power generation.
[0007] The porous monolayer graphene film in this invention is prepared by chemical vapor deposition and etched by ozone (O3) vaporization. The porous monolayer graphene film exhibits a uniform and controllable nanopore structure, high porosity, and excellent ion selectivity, making it suitable for salinity gradient power generation. The method of this invention is simple, safe, and environmentally friendly.
[0008] This invention obtains graphene films with different pore sizes and porosities by controlling etching conditions, which can achieve directional selective migration of cations, thereby improving the power density and energy conversion efficiency of salinity gradient power generation devices.
[0009] The method of this invention is simple to operate, highly controllable, and produces a uniform and highly repeatable pore structure. The resulting porous monolayer graphene film is continuous, intact, and flexible, exhibiting excellent mechanical stability.
[0010] A method for preparing a porous single-layer graphene film is specifically carried out according to the following steps:
[0011] 1. The copper foil is ultrasonically cleaned and then dried with nitrogen to obtain the pretreated copper foil.
[0012] 2. The pretreated copper foil is placed in the reaction chamber of the chemical vapor deposition equipment and reduced in a mixed atmosphere of hydrogen and argon at 1000℃. After the reduction is completed, the hydrogen and argon are stopped to obtain the reduced copper foil.
[0013] 3. Methane gas and hydrogen gas are introduced into the reaction chamber at a volume ratio of 3:1 to grow monolayer graphene and obtain a monolayer graphene film.
[0014] IV. The single-layer graphene film is etched under an ozone atmosphere, and oxygen-containing functional groups are introduced through ozone oxidation to obtain an ozone-treated single-layer graphene film.
[0015] 5. The ozone-treated monolayer graphene is reduced in a hydrogen atmosphere. During the reduction process, some C atoms are removed to form nanopores, resulting in a porous monolayer graphene film.
[0016] Application of a porous monolayer graphene in salinity gradient power generation.
[0017] The beneficial effects of this invention are:
[0018] 1. In this invention, the O3 vaporization method is used to form nanopores on graphene, avoiding acid etching and traditional liquid-phase chemical corrosion processes.
[0019] II. By adjusting the ozone concentration, etching temperature and time, this invention can precisely control the pore size distribution and porosity, and the prepared porous monolayer graphene film has a stable structure and small batch-to-batch differences, making it suitable for large-scale production.
[0020] Third, the porous monolayer graphene membrane prepared by this invention has high ion permeability, effectively reducing ion transport resistance and improving ion migration rate.
[0021] IV. When this invention is used in a salinity gradient energy generation system, the power generation density can reach 5W / m³. 2 ~20W / m 2 It significantly improves upon traditional polymer semipermeable membranes;
[0022] V. This invention provides a new approach for the development of graphene-based ion-selective membranes, which can be further extended to fields such as energy conversion and ion sieving. Attached Figure Description
[0023] Figure 1 This is a high-resolution transmission electron microscope image of the monolayer graphene film prepared in Example 1 of this invention with spherical aberration correction.
[0024] Figure 2 This is a high-resolution transmission electron microscope image with spherical aberration correction of the single-layer porous graphene film prepared in Example 1 of this invention;
[0025] Figure 3 This is the Raman spectrum of the monolayer graphene film prepared in Example 1 of this invention;
[0026] Figure 4 This is the Raman spectrum of the monolayer porous graphene film prepared in Example 1 of this invention;
[0027] Figure 5 This relates to the salt gradient energy generation performance of the single-layer porous graphene membrane prepared in Example 1 of this invention. Detailed Implementation
[0028] The present application is further illustrated below with reference to specific embodiments. The following descriptions are merely a few embodiments of the present application and are not intended to limit the present application in any way. Although the present application discloses preferred embodiments as follows, they are not intended to limit the present application. Any modifications or variations made by those skilled in the art without departing from the scope of the technical solution of the present application using the disclosed technical content are equivalent to equivalent implementation cases and all fall within the scope of the technical solution.
[0029] Unless otherwise specified, the raw materials used in the embodiments of this application are all purchased commercially and used directly without any special treatment.
[0030] The analysis method in the embodiments of this application is as follows:
[0031] Morphological analysis was performed using a Thermo Fisher Scientific Spectra 300 transmission electron microscope.
[0032] Raman analysis was performed using a Horiba France SAS XploRA INV Raman scattering spectrometer.
[0033] Salinity gradient energy generation performance analysis was performed using the Keithley SourceMeter® 2450 digital source meter.
[0034] Specific Implementation Method 1: This implementation method is a method for preparing a porous single-layer graphene film, specifically completed according to the following steps:
[0035] 1. The copper foil is ultrasonically cleaned and then dried with nitrogen to obtain the pretreated copper foil.
[0036] 2. The pretreated copper foil is placed in the reaction chamber of the chemical vapor deposition equipment and reduced in a mixed atmosphere of hydrogen and argon at 1000℃. After the reduction is completed, the hydrogen and argon are stopped to obtain the reduced copper foil.
[0037] 3. Methane gas and hydrogen gas are introduced into the reaction chamber at a volume ratio of 3:1 to grow monolayer graphene and obtain a monolayer graphene film.
[0038] IV. The single-layer graphene film is etched under an ozone atmosphere, and oxygen-containing functional groups are introduced through ozone oxidation to obtain an ozone-treated single-layer graphene film.
[0039] 5. The ozone-treated monolayer graphene is reduced in a hydrogen atmosphere. During the reduction process, some C atoms are removed to form nanopores, resulting in a porous monolayer graphene film.
[0040] Specific Implementation Method Two: This implementation method differs from Specific Implementation Method One in that: in step one, propanol and isopropanol are used to ultrasonically clean the copper foil for 5 to 30 minutes. The other steps are the same as in Specific Implementation Method One.
[0041] Specific Implementation Method Three: This implementation method differs from Specific Implementation Method One or Two in that: the flow rate of hydrogen in the hydrogen-argon mixed atmosphere described in step two is selected from any value among 10 sccm, 15 sccm, 20 sccm, 25 sccm, and 30 sccm, or a range between any two of the above values; the flow rate of argon in the hydrogen-argon mixed atmosphere described in step two is selected from any value among 100 sccm, 150 sccm, 200 sccm, 250 sccm, and 300 sccm, or a range between any two of the above values. Other steps are the same as in Specific Implementation Method One or Two.
[0042] Specific Implementation Method Four: This implementation method differs from Specific Implementation Methods One to Three in that: the pressure during the reduction process in step two is selected from any value among 400 torr, 450 torr, 500 torr, 550 torr, 600 torr, 650 torr, and 700 torr, or a range between any two of the above values; the reduction time in step two is selected from any value among 20 min, 30 min, 40 min, 50 min, and 60 min, or a range between any two of the above values. Other steps are the same as in Specific Implementation Methods One to Three.
[0043] Specific Implementation Method Five: This implementation method differs from Specific Implementation Methods One to Four in the following ways: The growth time in step three is selected from any value among 20 min, 25 min, 30 min, 35 min, 40 min, and 45 min, or a range between any two of the above values; the pressure during growth in step three is selected from any value among 0.3 torr, 0.35 torr, 0.4 torr, 0.45 torr, and 0.5 torr, or a range between any two of the above values; the growth temperature in step three is selected from any value among 800℃, 850℃, 900℃, 950℃, and 1000℃, or a range between any two of the above values. Other steps are the same as in Specific Implementation Methods One to Four.
[0044] Specific Implementation Method Six: This implementation method differs from Specific Implementation Methods One to Five in the following ways: The etching temperature in step four is selected from any value among 30℃, 40℃, 50℃, 60℃, 70℃, 80℃, 90℃, and 100℃, or a range between any two of the above values; the ozone concentration in step four is selected from any value among 160mg / L, 180mg / L, 200mg / L, 220mg / L, 240mg / L, 260mg / L, 280mg / L, and 300mg / L, or a range between any two of the above values; the etching time in step four is 1h to 2h. Other steps are the same as in Specific Implementation Methods One to Five.
[0045] Specific Implementation Method Seven: This implementation method differs from Specific Implementation Methods One to Six in the following ways: The reduction temperature in step five is selected from any value among 500℃, 550℃, 600℃, 650℃, and 700℃, or a range between any two of the above values; the hydrogen flow rate in step five is selected from any value among 10 sccm, 15 sccm, 20 sccm, 25 sccm, and 30 sccm, or a range between any two of the above values; the pressure during the reduction process in step five is selected from any value among 400 torr, 450 torr, 500 torr, 550 torr, 600 torr, 650 torr, and 700 torr, or a range between any two of the above values; the reduction time in step five is selected from any value among 20 min, 30 min, 40 min, 50 min, and 60 min, or a range between any two of the above values. Other steps are the same as in Specific Implementation Methods One to Six.
[0046] Specific Implementation Method Eight: This implementation method is prepared according to any one of Specific Implementation Methods One through Seven; the porous monolayer graphene film has a single-layer structure with a pore size of 0.3~5nm and a porosity of 10. 12 cm -2The porous monolayer graphene film has a uniform pore distribution on its surface, with no obvious cracks or macroscopic defects.
[0047] Specific implementation method nine: This implementation method is an application of porous single-layer graphene in salinity gradient power generation.
[0048] Specific Implementation Method Ten: This implementation method differs from Specific Implementation Methods One to Nine in that: the application of a porous single-layer graphene film in salinity gradient power generation is specifically accomplished according to the following steps:
[0049] 1. Using porous single-layer graphene membranes as semi-permeable membrane materials, assemble them into a salt gradient energy generation device;
[0050] The salinity gradient power generation device described in step one includes a high-concentration side, a low-concentration side, and a porous monolayer graphene membrane sandwiched between the two.
[0051] 2. A 0.5 mol / L NaCl solution is injected into the high concentration side to simulate seawater; a 0.01 mol / L NaCl solution is injected into the low concentration side to simulate freshwater; the ion selectivity of the membrane enables the directional migration of cations, thereby forming a potential difference and outputting electrical energy.
[0052] The power density of the salinity gradient energy generation device can reach 5W / m³. 2 ~20W / m 2 The power generation process is stable and has high energy conversion efficiency. Other steps are the same as those in specific implementation methods one through nine.
[0053] The beneficial effects of the present invention are verified using the following embodiments:
[0054] Example 1: A method for preparing a single-layer porous graphene membrane, specifically comprising the following steps:
[0055] 1. Select copper foil as the substrate, and ultrasonically clean the copper foil in acetone and isopropanol for 20 minutes each to remove surface organic contaminants. Then dry it with nitrogen to obtain the pretreated copper foil.
[0056] 2. Place the pretreated copper foil into the reaction chamber of the chemical vapor deposition equipment. Under a pressure of 600 torr, introduce 10 sccm of hydrogen and 100 sccm of argon, heat to 1000℃ and hold for 30 min. After the reduction is completed, stop introducing hydrogen and argon to obtain the reduced copper foil.
[0057] 3. At 900℃ and 0.3 torr, methane gas and hydrogen gas were introduced into the reaction chamber at a volume ratio of 3:1 to obtain monolayer graphene for 30 min, resulting in a monolayer graphene film grown on the copper foil surface.
[0058] IV. Place the monolayer graphene film in an ozone reaction environment and treat it at 40°C with an ozone concentration of 220 mg / L for 1.5 h. Oxygen-containing defects are introduced on the graphene surface through oxidation to obtain an ozone-treated monolayer graphene film.
[0059] 5. Place the ozone-treated monolayer graphene in a tube furnace, introduce 15 sccm of hydrogen gas, and perform heat treatment at a pressure of 450 torr, a temperature of 600℃, and a treatment time of 30 min to obtain a monolayer porous graphene membrane.
[0060] Example 2: A method for preparing a single-layer porous graphene membrane, specifically carried out according to the following steps:
[0061] 1. Select copper foil as the substrate, and ultrasonically clean the copper foil in acetone and isopropanol for 20 minutes each to remove surface organic contaminants. Then dry it with nitrogen to obtain the pretreated copper foil.
[0062] 2. Place the pretreated copper foil into the reaction chamber of the chemical vapor deposition equipment. Under a pressure of 600 torr, introduce 10 sccm of hydrogen and 100 sccm of argon, heat to 1000℃ and hold for 30 min. After the reduction is completed, stop introducing hydrogen and argon to obtain the reduced copper foil.
[0063] 3. At 900℃ and 0.3 torr, methane gas and hydrogen gas were introduced into the reaction chamber at a volume ratio of 3:1 to obtain monolayer graphene for 30 min, resulting in a monolayer graphene film grown on the copper foil surface.
[0064] IV. Place the monolayer graphene film in an ozone reaction environment and treat it at 40°C with an ozone concentration of 260 mg / L for 2 hours. Oxygen-containing defects are introduced on the graphene surface through oxidation, resulting in an ozone-treated monolayer graphene film.
[0065] 5. Place the ozone-treated monolayer graphene in a tube furnace, introduce 15 sccm of hydrogen gas, and perform heat treatment at a pressure of 450 torr, a temperature of 600℃, and a treatment time of 30 min to obtain a monolayer porous graphene membrane.
[0066] Example 3: A method for preparing a porous single-layer graphene film, specifically carried out according to the following steps:
[0067] 1. Select copper foil as the substrate, and ultrasonically clean the copper foil in acetone and isopropanol for 20 minutes each to remove surface organic contaminants. Then dry it with nitrogen to obtain the pretreated copper foil.
[0068] 2. Place the pretreated copper foil into the reaction chamber of the chemical vapor deposition equipment. Under a pressure of 600 torr, introduce 10 sccm of hydrogen and 100 sccm of argon, heat to 1000℃ and hold for 30 min. After the reduction is completed, stop introducing hydrogen and argon to obtain the reduced copper foil.
[0069] 3. At 900℃ and 0.3 torr, methane gas and hydrogen gas were introduced into the reaction chamber at a volume ratio of 3:1 to obtain monolayer graphene for 30 min, resulting in a monolayer graphene film grown on the copper foil surface.
[0070] IV. Place the monolayer graphene film in an ozone reaction environment and treat it at 45°C with an ozone concentration of 260 mg / L for 2 hours. Oxygen-containing defects are introduced on the graphene surface through oxidation, resulting in an ozone-treated monolayer graphene film.
[0071] 5. Place the ozone-treated monolayer graphene in a tube furnace, introduce 15 sccm of hydrogen gas, and perform heat treatment at a pressure of 450 torr, a temperature of 600℃, and a treatment time of 30 min to obtain a monolayer porous graphene membrane.
[0072] Characterization:
[0073] AC-HRTEM images of the sample before the introduction of pore size into the graphene membrane are shown below. Figure 1 As shown;
[0074] Figure 1 This is a high-resolution transmission electron microscope image of the monolayer graphene film prepared in Example 1 of this invention with spherical aberration correction.
[0075] Figure 1 The graphene film is uniform and continuous, exhibiting a single-layer structure with a clear six-membered ring structure and no pores. The morphology of other samples is similar to that of the graphene film. Figure 1 resemblance.
[0076] AC-HRTEM images of graphene membranes with introduced pore sizes are shown below. Figure 2 As shown;
[0077] Figure 2 This is a high-resolution transmission electron microscope image with spherical aberration correction of the single-layer porous graphene film prepared in Example 1 of this invention;
[0078] Figure 2 The results show that the pore size distribution of sample 1 is uniform after drilling, and is concentrated in the range of 0.2~0.4nm.
[0079] Raman spectra of graphene films before the introduction of nanopores, such as... Figure 3 As shown;
[0080] Figure 3This is the Raman spectrum of the monolayer graphene film prepared in Example 1 of this invention;
[0081] Figure 3 The Raman spectrum shows 1350 cm⁻¹ -1 The absence of a distinct D peak nearby indicates that the graphene is defect-free.
[0082] Raman spectra of graphene films with introduced nanopores, as shown in the figure. Figure 4 As shown;
[0083] Figure 4 This is the Raman spectrum of the monolayer porous graphene film prepared in Example 1 of this invention;
[0084] Figure 4 The Raman spectrum of the graphene film is shown at 1350 cm⁻¹. -1 The significant enhancement of the nearby D peak indicates that drilling introduced a large number of edge defects.
[0085] Application Example 1: The application of a single-layer porous graphene film prepared in Example 1 in salinity gradient power generation is specifically carried out according to the following steps:
[0086] 1. The porous monolayer graphene membrane prepared in Example 1 is used as a semi-permeable membrane material to assemble a salt gradient energy generation device.
[0087] The salinity gradient power generation device described in step one includes a high-concentration side, a low-concentration side, and a porous monolayer graphene membrane sandwiched between the two.
[0088] 2. A 0.5 mol / L NaCl solution is injected into the high-concentration side to simulate seawater; a 0.01 mol / L NaCl solution is injected into the low-concentration side to simulate freshwater; the ion selectivity of the membrane enables the directional migration of cations, thereby creating a potential difference and outputting electrical energy. Figure 5 As shown;
[0089] Figure 5 This relates to the salt gradient energy generation performance of the single-layer porous graphene membrane prepared in Example 1 of this invention.
[0090] Figure 5 The results show that in a NaCl solution concentration gradient system of 50 times (i.e., 0.5 M / 0.01 M NaCl), the power density first increases and then decreases with increasing external resistance, reaching a low level around 10. 4 It reaches its maximum value near Ω, with a maximum power density of approximately 7.8 W / m². 2 The current density gradually decreases with the increase of the external resistance, exhibiting typical ohmic decay characteristics, indicating that the ion transport process is stable and significantly regulated by the external circuit.
Claims
1. A method for preparing a porous monolayer graphene membrane, characterized in that... The preparation method is specifically carried out according to the following steps:
1. The copper foil is ultrasonically cleaned and then dried with nitrogen to obtain the pretreated copper foil.
2. The pretreated copper foil is placed in the reaction chamber of the chemical vapor deposition equipment and reduced in a mixed atmosphere of hydrogen and argon at 1000℃. After the reduction reaction is completed, the hydrogen and argon are stopped to obtain the reduced copper foil.
3. Methane gas and hydrogen gas are introduced into the reaction chamber at a volume ratio of 3:1 to grow monolayer graphene and obtain a monolayer graphene film. IV. The single-layer graphene film is etched under an ozone atmosphere, and oxygen-containing functional groups are introduced through ozone oxidation to obtain an ozone-treated single-layer graphene film.
5. The ozone-treated monolayer graphene is reduced in a hydrogen atmosphere. During the reduction process, some C atoms are removed to form nanopores, resulting in a porous monolayer graphene film.
2. The method for preparing a porous monolayer graphene membrane according to claim 1, characterized in that... In step one, the copper foil is ultrasonically cleaned using propanol and isopropanol for 5 to 30 minutes.
3. The method for preparing a porous single-layer graphene membrane according to claim 1, characterized in that... In step two, the flow rate of hydrogen in the mixed atmosphere of hydrogen and argon is selected from any value of 10 sccm, 15 sccm, 20 sccm, 25 sccm, 30 sccm or a range between any two of the above values; the flow rate of argon in the mixed atmosphere of hydrogen and argon in step two is selected from any value of 100 sccm, 150 sccm, 200 sccm, 250 sccm, 300 sccm or a range between any two of the above values.
4. The method for preparing a porous single-layer graphene membrane according to claim 1, characterized in that... The pressure during the reduction process in step two is selected from any value of 400 torr, 450 torr, 500 torr, 550 torr, 600 torr, 650 torr, or 700 torr, or a range between any two of the above points; the reduction time mentioned in step two is selected from any value of 20 min, 30 min, 40 min, 50 min, or 60 min, or a range between any two of the above points.
5. The method for preparing a porous single-layer graphene membrane according to claim 1, characterized in that... The growth time mentioned in step three is selected from any value of 20 min, 25 min, 30 min, 35 min, 40 min, 45 min, or any range between any two of the above points; the pressure during growth in step three is selected from any value of 0.3 torr, 0.35 torr, 0.4 torr, 0.45 torr, 0.5 torr, or any range between any two of the above points; the growth temperature mentioned in step three is selected from any value of 800℃, 850℃, 900℃, 950℃, 1000℃, or any range between any two of the above points.
6. The method for preparing a porous single-layer graphene membrane according to claim 1, characterized in that... The etching temperature in step four is selected from any value among 30℃, 40℃, 50℃, 60℃, 70℃, 80℃, 90℃, and 100℃, or a range between any two of the above values; the ozone concentration in step four is selected from any value among 160mg / L, 180mg / L, 200mg / L, 220mg / L, 240mg / L, 260mg / L, 280mg / L, and 300mg / L, or a range between any two of the above values; the etching time in step four is 1h to 2h.
7. The method for preparing a porous monolayer graphene membrane according to claim 1, characterized in that... The reduction temperature in step five is selected from any value among 500℃, 550℃, 600℃, 650℃, and 700℃, or a range between any two of the above points; the hydrogen flow rate in step five is selected from any value among 10 sccm, 15 sccm, 20 sccm, 25 sccm, and 30 sccm, or a range between any two of the above points; the pressure during the reduction process in step five is selected from any value among 400 torr, 450 torr, 500 torr, 550 torr, 600 torr, 650 torr, and 700 torr, or a range between any two of the above points; the reduction time in step five is selected from any value among 20 min, 30 min, 40 min, 50 min, and 60 min, or a range between any two of the above points.
8. A porous single-layer graphene membrane, characterized in that... It is prepared according to the preparation method described in any one of claims 1 to 7; the porous monolayer graphene film has a single-layer structure, a pore size of 0.3 to 5 nm, and a porosity of 10. 12 cm -2 The porous monolayer graphene film has a uniform pore distribution on its surface, with no obvious cracks or macroscopic defects.
9. The application of a porous single-layer graphene membrane as described in claim 8, characterized in that... Application of a porous monolayer graphene in salinity gradient power generation.
10. The application of a porous monolayer graphene membrane according to claim 9, characterized in that... The application of a porous monolayer graphene membrane in salinity gradient power generation is specifically accomplished through the following steps:
1. Using porous single-layer graphene membranes as semi-permeable membrane materials, assemble them into a salt gradient energy generation device; The salinity gradient power generation device described in step one includes a high-concentration side, a low-concentration side, and a porous monolayer graphene membrane sandwiched between the two.
2. A 0.5 mol / L NaCl solution is injected into the high concentration side to simulate seawater; a 0.01 mol / L NaCl solution is injected into the low concentration side to simulate freshwater; the ion selectivity of the membrane enables the directional migration of cations, thereby forming a potential difference and outputting electrical energy. The power density of the salinity gradient energy generation device can reach 5W / m³. 2 ~20W / m 2 The power generation process is stable and has high energy conversion efficiency.