Carbon-based tannic acid-Fe composite aerogel with good power generation performance as well as preparation method and application of carbon-based tannic acid-Fe composite aerogel

Abstract

The invention relates to the technical field of nano composite materials, in particular to a carbon-based tannic acid-Fe composite aerogel with good power generation performance and a preparation method and application thereof. According to the aerogel, through the design of a single-oriented structure and the modification of a tannic acid-Fe coating on the surface, the water transmission capacity and the interface charge migration efficiency in the material are effectively enhanced. In a 3D working mode, the material shows excellent electric output performance, and the power density of the material can reach 48.92 under a sun illumination condition and is remarkably improved compared with that of unmodified carbon-based aerogel.

Description

Technical Field

[0001] This invention relates to the field of nanocomposite materials technology, specifically to a carbon-based tannic acid-Fe composite aerogel with good power generation performance, its preparation method, and its applications. Background Technology

[0002] In today's era, with the accelerating pace of industrial modernization and the continuous rise in energy consumption, the current reliance on traditional petroleum energy urgently requires breakthroughs and replacements in new energy technologies. Currently, various simple green energy generators are under widespread development, such as piezoelectric, triboelectric, thermoelectric, and hydroelectric generators. Among them, hydroelectric power generation technology possesses significant resource advantages due to the fact that over 70% of the Earth's surface is covered by natural water bodies. Unlike traditional power generation methods that require complex power conversion systems and large equipment, hydroelectric power generation is mainly based on the interaction between evaporation-induced water flow and the surface of micro-nano channels, achieving continuous and stable power output without relying on chemical reactions. Currently, hydroelectric power generation technology has made some progress in multi-energy complementarity and efficient energy utilization. Carbon materials, due to their excellent photothermal conversion performance, electrical properties, physicochemical stability, cost advantages, and environmental friendliness, show significant potential in hydroelectric power generation. However, conventional carbon materials generally have poor water wettability and transport capabilities, limiting further improvements in their electrical output performance. To address these issues, this invention proposes a carbon-based tannic acid-Fe composite aerogel. This material significantly improves hydrovoltaic power generation performance by introducing a tannic acid-Fe composite coating, which optimizes water transport performance and enhances interfacial charge migration efficiency.

[0003] In view of the above-mentioned defects, the inventors of this invention have finally obtained this invention after a long period of research and practice. Summary of the Invention

[0004] The purpose of this invention is to solve the problem that conventional carbon materials have poor water wettability and transport capacity, resulting in generally low electrical output performance. The invention provides a carbon-based tannic acid-Fe composite aerogel with good power generation performance, its preparation method, and its application.

[0005] To achieve the above objectives, this invention discloses a carbon-based tannic acid-Fe composite aerogel with good power generation performance, its preparation method, and its applications, comprising the following steps:

[0006] S1, Preparation of chitosan-graphene oxide aerogel: Chitosan-graphene oxide solution is poured into a polystyrene mold, frozen by unidirectional cryogenic casting, and then freeze-dried to obtain chitosan-graphene oxide aerogel with unidirectional structure. Carbonization is carried out under N2 atmosphere to obtain carbon-based aerogel with unidirectional structure.

[0007] S2, Preparation of carbon-based tannic acid-Fe composite aerogel: Prepare a tannic acid-aminopropyltriethoxysilane solution, immerse the carbon-based aerogel in the tannic acid-aminopropyltriethoxysilane solution, wash off excess tannic acid-aminopropyltriethoxysilane solution on the surface with deionized water, then immerse it in ferric sulfate solution to form a tannic acid-Fe coating, wash with deionized water and dry to obtain a unidirectional carbon-based tannic acid-Fe composite aerogel.

[0008] In step S1, the mass ratio of chitosan to graphene oxide in the chitosan-graphene oxide solution is 15:5.

[0009] In step S1, the specific process of the unidirectional cryogenic casting method is as follows: the chitosan-graphene oxide mixture is poured into the polystyrene mold on the cold plate, and liquid nitrogen is poured in to control the temperature at about -30 ℃.

[0010] In step S1, the carbonization process is as follows: heating from 20 ℃ to 500 ℃ at a heating rate of 2 ℃ / min and holding for 1 h; heating from 500 ℃ to 800 ℃ at a heating rate of 5 ℃ / min and holding for 2 h.

[0011] In step S2, the preparation method of tannic acid-aminopropyltriethoxysilane solution is as follows: tannic acid-Tris buffer solution and aminopropyltriethoxysilane solution are mixed at a volume ratio of 5:1 and reacted for 1 h.

[0012] The tannic acid-Tris buffer solution is prepared as follows: 0.2 g of tannic acid powder is dissolved in 100 mL of Tris-HCl buffer solution and sonicated for 10 min to obtain the tannic acid-Tris buffer solution. The pH of the Tris-HCl buffer solution is 8.5.

[0013] The preparation method of the aminopropyltriethoxysilane solution is as follows: 0.2 g of aminopropyltriethoxysilane is dissolved in 20 mL of anhydrous ethanol.

[0014] In step S2, the ferric sulfate solution is prepared as follows: 0.2 g of ferric sulfate hydrate is dissolved in 100 mL of water and reacted for 1 h.

[0015] This invention also discloses a carbon-based tannic acid-Fe composite aerogel with good power generation performance prepared by the above-described method. The carbon-based tannic acid-Fe composite aerogel comprises a carbon-based aerogel oriented pore structure and a tannic acid-Fe coating. The tannic acid-Fe coating is uniformly distributed within the inner walls of the pores of the carbon-based aerogel oriented pore structure. The carbon-based tannic acid-Fe composite aerogel exhibits good power generation performance at 1 kW / m³. 2 Under simulated sunlight intensity, the electrical output power density is 48.92 μW / cm².-2 .

[0016] This invention also discloses the application of the above-mentioned carbon-based tannic acid-Fe composite aerogel with good power generation performance in hydrovolt power generation.

[0017] The carbon-based tannic acid-Fe composite aerogel prepared in this invention comprises a unidirectional porous structure and a hydrophilic tannic acid-Fe coating. This aerogel exhibits a stable structure and good power generation performance. The unidirectional porous structure of the aerogel facilitates water transport while ensuring continuous and efficient water evaporation. Modifying the carbon-based porous aerogel with a tannic acid-Fe coating enhances its hydrophilicity and increases the number of ion sites. Compared to carbon-based aerogels, the carbon-based tannic acid-Fe composite aerogel demonstrates superior power generation performance.

[0018] Compared with existing technologies, the beneficial effects of this invention are as follows: the carbon-based tannic acid-Fe composite aerogel prepared by this invention can improve the power generation performance of carbon-based aerogels. In contrast, the electrical output performance of carbon-based tannic acid-other metal composite aerogels in simulated seawater is weak, indicating that the design of hydroelectric power generation for carbon-based materials requires surface modification to optimize water transport and charge transfer in order to enhance power generation performance. Attached Figure Description

[0019] Figure 1 Scanned image of carbon-based aerogel;

[0020] Figure 2 Photographs and pore scan images of carbon-based tannic acid-Fe composite aerogels;

[0021] Figure 3 (a) Elemental distribution diagram and (b) infrared spectrum of carbon-based tannic acid-Fe composite aerogel;

[0022] Figure 4 (a) Experimental operation diagram and (b) thermal infrared image of carbon-based and carbon-based tannic acid-Fe composite aerogels for transporting cold water;

[0023] Figure 5 (a) Voltage and (b) Current plots of carbon-based, carbon-based tannic acid, carbon-based tannic acid-Zn, carbon-based tannic acid-Mg, carbon-based tannic acid-Cu, carbon-based tannic acid-Mn, carbon-based tannic acid-Ni, carbon-based tannic acid-Co, carbon-based tannic acid-Ca, carbon-based tannic acid-K, and carbon-based tannic acid-Fe aerogels;

[0024] Figure 6(a) Internal resistance and (b) Electrical output power density diagrams for carbon-based, carbon-based tannic acid, carbon-based tannic acid-Zn, carbon-based tannic acid-Mg, carbon-based tannic acid-Cu, carbon-based tannic acid-Mn, carbon-based tannic acid-Ni, carbon-based tannic acid-Co, carbon-based tannic acid-Ca, carbon-based tannic acid-K, and carbon-based tannic acid-Fe aerogels;

[0025] Figure 7 (a) Voltage and (b) Current graphs showing the change in above-water length with a fixed underwater length of 4 mm.

[0026] Figure 8 The diagram shows the electrical output power density as the above-water length varies when the underwater length is fixed at 4 mm.

[0027] Figure 9 (a) Voltage and (b) Current graphs showing the change in underwater length when the above-water length is fixed at 8 mm;

[0028] Figure 10 The diagram shows the electrical output power density as the underwater length varies when the above-water length is fixed at 8 mm.

[0029] Figure 11 (a) Voltage and (b) Current plots of carbon-based tannic acid-Fe composite aerogels with ferric sulfate solution of 0.2% (w / v) and tannic acid solutions of 0.05%, 0.1%, 0.2%, 0.4%, 0.8%, and 1.6% (w / v) respectively.

[0030] Figure 12 Power output density diagrams of carbon-based tannic acid-Fe composite aerogels with ferric sulfate solution of 0.2% (w / v) and tannic acid solutions of 0.05%, 0.1%, 0.2%, 0.4%, 0.8%, and 1.6% (w / v) respectively.

[0031] Figure 13 (a) Voltage and (b) Current plots of carbon-based tannic acid-Fe composite aerogels with tannic acid solution of 0.2% (w / v) and ferric sulfate solution of 0, 0.025, 0.05, 0.1, 0.2, 0.4, 0.8, and 1.6% (w / v) fixed.

[0032] Figure 14 Power output density diagrams of carbon-based tannic acid-Fe composite aerogels with fixed tannic acid solution of 0.2% (w / v) and ferric sulfate solution of 0, 0.025, 0.05, 0.1, 0.2, 0.4, 0.8, and 1.6% (w / v);

[0033] Figure 15 The graph shows the stability test results of carbon-based tannic acid-Fe composite aerogel within 3600 s. Detailed Implementation

[0034] The above-mentioned and other technical features and advantages of the present invention will be described in more detail below with reference to the accompanying drawings.

[0035] Example 1

[0036] The specific steps for preparing carbon-based aerogels in this embodiment are as follows:

[0037] (1) Take 4 g of chitosan powder and mix it evenly into 98 mL of deionized water and 2 mL of acetic acid. Stir overnight to obtain a 4% chitosan solution.

[0038] (2) Take 0.4 g of graphene oxide powder and mix it evenly into 40 mL of deionized water. Disperse it in an ultrasonic crusher at 500 W for 5 min to obtain a graphene oxide solution of 10 mg / mL.

[0039] (3) Mix the prepared chitosan and graphene oxide solution at a mass ratio of 15:5, and ultrasonically crush them at 700 W for 10 min to obtain a chitosan-graphene oxide mixed solution.

[0040] (4) Orientation freezing of chitosan-graphene oxide mixed solution: The mixture was poured into a cylindrical mold on a cold plate, and liquid nitrogen was poured in to control the temperature at -30 ℃. Then, the initial chitosan-graphene oxide aerogel was obtained by freeze drying for 60 h;

[0041] (5) Chitosan-graphene oxide aerogel was calcined in a nitrogen atmosphere. The carbonization process was to raise the temperature from 20 ℃ to 500 ℃ at a rate of 2 ℃ / min and hold for 1 h; then raise the temperature from 500 ℃ to 800 ℃ at a rate of 5 ℃ / min and hold for 2 h to obtain carbon-based aerogel.

[0042] Figure 1 The image shows a scanned image of a carbon-based aerogel. The scanned image shows that the longitudinal cross-section of the carbon-based aerogel has vertical and parallel pores from bottom to top, and the cross-section exhibits a honeycomb structure.

[0043] Example 2

[0044] The specific steps for preparing carbon-based tannic acid-Fe composite aerogel in this embodiment are as follows:

[0045] (1) Preparation of tannic acid-Tris buffer solution: Dissolve 0.2 g of tannic acid powder in 100 mL of Tris-HCl buffer solution (pH=8.5) and sonicate for 10 min to obtain tannic acid-Tris buffer solution;

[0046] (2) Preparation of tannic acid-aminopropyltriethoxysilane (TA-APTES) solution: Dissolve 0.2 g APTES in 20 mL of anhydrous ethanol, and then slowly add it to tannic acid buffer solution and mix well to obtain TA-APTES solution;

[0047] (3) The carbon-based aerogel was immersed in TA-APTES solution for 1 h, and after washing to remove excess TA-APTES solution, it was immersed in 0.2% (w / v) ferric sulfate solution for 1 h to obtain carbon-based tannic acid-Fe composite aerogel.

[0048] Figure 2 These are photographs and pore scanning images of a carbon-based tannic acid-Fe composite aerogel. The images show that the tannic acid-Fe coating is uniformly dispersed on the aerogel surface.

[0049] Figure 3 The images show the elemental distribution and infrared spectrum of the carbon-based tannic acid-Fe composite aerogel. Graph a shows the uniform distribution of Fe, Si, N, and O elements, while graph b shows the wavelength at 1635 cm⁻¹. -1 1540 cm -1 , and 760 cm -1 The absorption peaks that appear at certain times correspond to the -C=N, benzene ring stretching vibration, and tannic acid-Fe vibration, respectively, indicating that tannic acid-Fe was successfully modified on the aerogel surface.

[0050] Figure 4 The thermal infrared images of carbon-based and carbon-based tannic acid-Fe composite aerogels for transporting cold water show that the carbon-based aerogel with the tannic acid-Fe coating transports cold water from the bottom to the top at a faster speed, proving that the carbon-based aerogel with the tannic acid-Fe coating has a stronger water transport capacity.

[0051] Example 3

[0052] In this embodiment, aerogels modified with coordination coatings of different metal salts and tannic acid were prepared and their power generation performance was tested.

[0053] (1) Preparation of carbon-based, carbon-based tannic acid, carbon-based tannic acid-Zn, carbon-based tannic acid-Mg, carbon-based tannic acid-Cu, carbon-based tannic acid-Mn, carbon-based tannic acid-Ni, carbon-based tannic acid-Co, carbon-based tannic acid-Ca, and carbon-based tannic acid-K aerogels respectively: The carbon-based aerogel was immersed in TA-APTES solution, and after washing, it was immersed in water, 0.2 % (w / v) zinc chloride, magnesium chloride, copper chloride, manganese chloride, nickel chloride, cobalt chloride, calcium chloride, and potassium chloride solution respectively to obtain carbon-based tannic acid, carbon-based tannic acid-Zn, carbon-based tannic acid-Mg, carbon-based tannic acid-Cu, carbon-based tannic acid-Mn, carbon-based tannic acid-Ni, carbon-based tannic acid-Co, carbon-based tannic acid-Ca, and carbon-based tannic acid-K aerogels;

[0054] (2) The aerogel immersed in 3.5 wt% NaCl solution was placed in a self-made silver-carbon cloth electrode sheet. After the xenon lamp was turned on and the light intensity stabilized, the light intensity on the upper surface of the aerogel was adjusted to 1 kW / m. 2 Use a multimeter to measure its voltage, current, power density, etc.

[0055] Figure 5 a and 5b are voltage and current diagrams for carbon-based, carbon-based tannic acid, carbon-based tannic acid-Zn, carbon-based tannic acid-Mg, carbon-based tannic acid-Cu, carbon-based tannic acid-Mn, carbon-based tannic acid-Ni, carbon-based tannic acid-Co, carbon-based tannic acid-Ca, carbon-based tannic acid-K, and carbon-based tannic acid-Fe aerogels. It can be seen that the voltage of tannic acid-Fe is 387.25 mV and the current is 57.94 μA, which is superior to the coordination of other metal salts with tannic acid.

[0056] Figure 6 a represents the internal resistance diagrams of carbon-based, carbon-based tannic acid, carbon-based tannic acid-Zn, carbon-based tannic acid-Mg, carbon-based tannic acid-Cu, carbon-based tannic acid-Mn, carbon-based tannic acid-Ni, carbon-based tannic acid-Co, carbon-based tannic acid-Ca, carbon-based tannic acid-K, and carbon-based tannic acid-Fe aerogels. It can be seen that tannic acid-Fe has the lowest internal resistance, proving that the tannic acid-Fe coating modification can form new conductive pathways on the carbon-based framework. At the same time, the introduction of Fe element not only increases the conductive active sites in the material, but also improves the disadvantage of tannic acid being easily oxidized. Figure 5 b is the electrical output power density diagram of carbon-based, carbon-based tannic acid, carbon-based tannic acid-Zn, carbon-based tannic acid-Mg, carbon-based tannic acid-Cu, carbon-based tannic acid-Mn, carbon-based tannic acid-Ni, carbon-based tannic acid-Co, carbon-based tannic acid-Ca, carbon-based tannic acid-K, and carbon-based tannic acid-Fe aerogels. It can be seen from the figure that the carbon-based aerogel modified with tannic acid-Fe has a higher electrical output power density than aerogels coordinated with tannic acid by other metal ions.

[0057] Example 4

[0058] This embodiment tests the electrical output performance of carbon-based tannic acid-Fe composite aerogels under different 3D modes, and the steps are as follows:

[0059] (1) The aerogel immersed in 3.5 wt% NaCl solution was placed in a self-made silver-carbon cloth electrode sheet. After the xenon lamp was turned on and the light intensity stabilized, the light intensity on the upper surface of the aerogel was adjusted to 1 kW / m. 2 Use a multimeter to measure its voltage, current, power density, etc.

[0060] (2) The electrical output performance of carbon-based tannic acid-Fe composite aerogels of different lengths in air and water was tested three times for each sample.

[0061] Figure 7 , Figure 8 The voltage, current, and electrical output power density are measured as the above-water length varies with a fixed underwater length of 4 mm. With a fixed underwater length, increasing the height of the carbon-based tannic acid-Fe composite aerogel exposed to air provides a larger evaporation area and extends the ion transport path, thus increasing the electrical output power density. However, when the overall length is too long, the current decreases, and the electrical output power density decreases.

[0062] Figure 9 , Figure 10 To determine the voltage, current, and electrical output power density as the underwater length changes when the above-water length is fixed at 8 mm, the study found that with a fixed above-water length, the electrical output power density initially increases and then decreases with increasing underwater length. Based on the above data, this study selected an optimal length of 8 mm in air and 4 mm in water for the unidirectional carbon-based tannic acid-Fe composite aerogel.

[0063] Example 5

[0064] This embodiment describes the control of tannic acid and ferric sulfate concentrations in carbon-based tannic acid-Fe composite aerogels, and the steps are as follows:

[0065] (1) Prepare tannic acid solutions of 0.05%, 0.1%, 0.2%, 0.4%, 0.8%, and 1.6% (w / v) respectively;

[0066] (2) Prepare ferric sulfate solutions of 0%, 0.025%, 0.05%, 0.1%, 0.2%, 0.4%, 0.8%, and 1.6% (w / v) respectively;

[0067] (3) Carbon-based tannic acid-Fe composite aerogels were synthesized according to the steps in Example 2, with the ferric sulfate solution being 0.2% (w / v) and the tannic acid solution being 0.05%, 0.1%, 0.2%, 0.4%, 0.8%, and 1.6% (w / v).

[0068] (4) Carbon-based tannic acid-Fe composite aerogels were synthesized according to the steps in Example 2, with fixed tannic acid solution of 0.2% (w / v) and ferric sulfate solution of 0, 0.025, 0.05, 0.1, 0.2, 0.4, 0.8 and 1.6% (w / v).

[0069] Figure 11 , Figure 12 The voltage, current, and electrical output power density of carbon-based tannic acid-Fe composite aerogels with ferric sulfate solution at 0.2% (w / v) and tannic acid solutions at 0.05%, 0.1%, 0.2%, 0.4%, 0.8%, and 1.6% (w / v) were determined. The figure shows that the electrical output power density initially increases and then decreases, reaching its maximum at a tannic acid solution concentration of 0.2% (w / v).

[0070] Figure 13 , Figure 14 The voltage, current, and electrical output power density of carbon-based tannic acid-Fe composite aerogels were measured with tannic acid solution at 0.2% (w / v) and ferric sulfate solution at 0, 0.025, 0.05, 0.1, 0.2, 0.4, 0.8, and 1.6% (w / v) concentrations. The graph shows that the electrical output power density initially increases and then decreases, reaching its maximum at 0.2% (w / v) ferric sulfate solution. Based on the above data, the optimal experimental group was selected in this study with both 0.2% (w / v) tannic acid solution and 0.2% (w / v) ferric sulfate solution.

[0071] Figure 15 The figure shows the stability test results of carbon-based tannic acid-Fe composite aerogel within 3600 s. As can be seen from the figure, the voltage fluctuation is very small within 3600 s, and no salt crystallization occurs on the aerogel surface, indicating its significant stability.

[0072] The above description is merely a preferred embodiment of the present invention and is illustrative rather than restrictive. Those skilled in the art will understand that many changes, modifications, and even equivalents can be made within the spirit and scope defined by the claims of the present invention, all of which will fall within the protection scope of the present invention.

Claims

1. A method for preparing a carbon-based tannic acid-Fe composite aerogel with good power generation performance, characterized in that, Includes the following steps: S1, Preparation of chitosan-graphene oxide aerogel: Chitosan-graphene oxide solution is poured into a polystyrene mold, frozen by unidirectional cryogenic casting, and then freeze-dried to obtain chitosan-graphene oxide aerogel with unidirectional structure. Carbonization is carried out under N2 atmosphere to obtain carbon-based aerogel with unidirectional structure. S2, Preparation of carbon-based tannic acid-Fe composite aerogel: Prepare a tannic acid-aminopropyltriethoxysilane solution, immerse the carbon-based aerogel in the tannic acid-aminopropyltriethoxysilane solution, wash off excess tannic acid-aminopropyltriethoxysilane solution on the surface with deionized water, then immerse it in ferric sulfate solution to form a tannic acid-Fe coating, wash with deionized water and dry to obtain a unidirectional carbon-based tannic acid-Fe composite aerogel.

2. The method for preparing a carbon-based tannic acid-Fe composite aerogel with good power generation performance as described in claim 1, characterized in that, In step S1, the mass ratio of chitosan to graphene oxide in the chitosan-graphene oxide solution is 15:

5.

3. The method for preparing a carbon-based tannic acid-Fe composite aerogel with good power generation performance as described in claim 1, characterized in that, In step S1, the specific process of the unidirectional cryogenic casting method is as follows: the chitosan-graphene oxide mixture is poured into the polystyrene mold on the cold plate, and liquid nitrogen is poured in to control the temperature at about -30 ℃.

4. The method for preparing a carbon-based tannic acid-Fe composite aerogel with good power generation performance as described in claim 1, characterized in that, In step S1, the carbonization process is as follows: heating from 20 ℃ to 500 ℃ at a heating rate of 2 ℃ / min and holding for 1 h; heating from 500 ℃ to 800 ℃ at a heating rate of 5 ℃ / min and holding for 2 h.

5. The method for preparing a carbon-based tannic acid-Fe composite aerogel with good power generation performance as described in claim 1, characterized in that, In step S2, the preparation method of tannic acid-aminopropyltriethoxysilane solution is as follows: tannic acid-Tris buffer solution and aminopropyltriethoxysilane solution are mixed at a volume ratio of 5:1 and reacted for 1 h.

6. The method for preparing a carbon-based tannic acid-Fe composite aerogel with good power generation performance as described in claim 5, characterized in that, The tannic acid-Tris buffer solution is prepared as follows: 0.2 g of tannic acid powder is dissolved in 100 mL of Tris-HCl buffer solution and sonicated for 10 min to obtain the tannic acid-Tris buffer solution. The pH of the Tris-HCl buffer solution is 8.

5.

7. The method for preparing a carbon-based tannic acid-Fe composite aerogel with good power generation performance as described in claim 5, characterized in that, The preparation method of the aminopropyltriethoxysilane solution is as follows: 0.2 g of aminopropyltriethoxysilane is dissolved in 20 mL of anhydrous ethanol.

8. The method for preparing a carbon-based tannic acid-Fe composite aerogel with good power generation performance as described in claim 1, characterized in that, In step S2, the ferric sulfate solution is prepared as follows: 0.2 g of ferric sulfate hydrate is dissolved in 100 mL of water and reacted for 1 h.

9. A carbon-based tannic acid-Fe composite aerogel with good power generation performance, prepared by the method according to any one of claims 1 to 8, characterized in that, The carbon-based tannic acid-Fe composite aerogel comprises a carbon-based aerogel oriented pore structure, a tannic acid-Fe coating, and the tannic acid-Fe coating being uniformly distributed within the inner walls of the pores of the carbon-based aerogel oriented pore structure. The carbon-based tannic acid-Fe composite aerogel operates at 1 kW / m³. 2 Under simulated solar illumination intensity, the electrical output power density is 48.92 μW / cm². -2 .

10. The application of a carbon-based tannic acid-Fe composite aerogel with good power generation performance as described in claim 9 in hydrovolt power generation.

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