Chitosan-based photovoltaic power generation device and system

Abstract

The invention provides a chitosan-based photovoltaic power generation device and system, and belongs to the technical field of new materials. The water photovoltaic power generation device provided by the invention adopts chitosan as a functional layer material, the chitosan is proved to have good biocompatibility and biodegradability, and a degradation product has no toxic or side effect on a human body, is not accumulated in the body and has no immunogenicity, so that the water photovoltaic power generation device has an extremely wide prospect in the field of biomedicine. The preparation method of the photovoltaic generator device provided by the invention is simple and easy, the production efficiency is high, good economical efficiency and biocompatibility are achieved, and a novel sustainable power supply scheme can be provided for human body wearable and implantable bioelectronic devices.

Description

Technical Field

[0001] The invention relates to the technical field of new materials, and in particular to a chitosan-based hydrovoltaic power generation device and system. Background Art

[0002] Hydrovoltaic power generation technology is a new power generation mode that uses the interaction between materials and fluid interfaces to generate electricity. It has attracted widespread attention from researchers in recent years due to its green, sustainable and low-cost advantages. Hydrovoltaic power generation devices use abundant atmospheric water vapor to achieve electrical energy output by converting the latent heat energy released by water vapor during condensation (that is, capturing the chemical potential energy change that occurs when water vapor condenses into liquid water. This transition from gas to liquid changes the potential energy of water molecules, thereby achieving electrical energy output). Its composition usually includes a hygroscopic composite functional layer material of the active layer and a pair of electrodes that transfer electrons.

[0003] The electricity generated by hydrovoltaic devices comes directly from the chemical energy generated by the diffusion of water vapor in the environment. Some materials, such as graphene oxide, will ionize carriers after interacting with water vapor, and because of the concentration gradient distribution of their functional groups, this gradient distribution causes the carriers to diffuse from the higher concentration end to the lower concentration end, thereby generating voltage and current, and realizing the output of electrical energy.

[0004] However, in the prior art, the biosafety of functional layer materials (such as graphene oxide) has not been verified, and the output current of the power generation device is small and the load capacity is poor. The manufacture of hydrovoltaic power generation devices requires pretreatment of materials, such as plasma oxidation, chemical oxidation, and electric field induction, to meet the requirements of different concentration gradient distributions, and the manufacturing process is relatively complicated. In addition, the manufactured device is relatively fragile and lacks flexibility. These factors limit the practical application of hydrovoltaic power generation devices.

[0005] For example, Chinese patent CN111641353A discloses a wet flexible power generation device and system, the functional layer material of which is poly (3,4-ethylenedioxythiophene) / polystyrene sulfonate film. The biosafety has not been verified and the application scenarios are relatively limited. The flexible wet gas generator device contains two PET substrates. Array-type through holes need to be opened on the first substrate and the second substrate to realize the series-parallel integration of the power generation device, and the integration scheme is relatively complicated. Summary of the invention

[0006] The purpose of the present invention is to provide a chitosan-based hydrovoltaic power generation device and system, which has better application prospects and performance.

[0007] In order to achieve the above-mentioned object of the invention, the present invention provides the following technical solutions:

[0008] The invention provides a chitosan-based hydrovoltaic power generation device, comprising a substrate, an electrode and a chitosan-organic acid-potassium chloride functional layer.

[0009] Preferably, the chitosan-organic acid-potassium chloride functional layer is prepared by a preparation method comprising the following steps:

[0010] Mixing a chitosan organic acid hydrogel dispersion and a potassium chloride solution to obtain a functional layer dispersion;

[0011] The functional layer dispersion is deposited on the electrode and dried to obtain the chitosan-organic acid-potassium chloride functional layer.

[0012] Preferably, the concentration of the chitosan organic acid hydrogel dispersion is 10 to 30 mg / mL;

[0013] The concentration of the potassium chloride solution is 250-350 mg / mL.

[0014] Preferably, the solvent used in the chitosan organic acid hydrogel dispersion is an organic weak acid solution.

[0015] Preferably, the organic weak acid solution is a citric acid solution;

[0016] The concentration of the citric acid solution is 50-150 mg / ml.

[0017] Preferably, the chitosan organic acid hydrogel dispersion and the potassium chloride solution are independently subjected to magnetic stirring before mixing;

[0018] The rotation speed of the magnetic stirring is 300-500 rpm.

[0019] Preferably, the total mixing time is 60 to 120 minutes.

[0020] Preferably, the deposition onto the electrode is carried out by dispensing or spin coating;

[0021] The substrate adopts a flexible PI substrate;

[0022] The electrodes include gold-plated electrodes and aluminum electrodes.

[0023] The present invention also provides a hydrovoltaic generator system, comprising a plurality of the above-mentioned chitosan-based hydrovoltaic power generation devices integrated in series.

[0024] The present invention also provides a hydrovoltaic generator system, comprising a plurality of the above-mentioned chitosan-based hydrovoltaic power generation devices integrated in parallel.

[0025] Beneficial effects of the present invention:

[0026] The hydrovoltaic power generation device provided by the present invention uses chitosan as a functional layer material. Chitosan has been proven to have good biocompatibility and biodegradability. The degradation products have no toxic side effects on the human body, do not accumulate in the body, and have no immunogenicity. Therefore, it has a very broad prospect in the biomedical field. The preparation method of the hydrovoltaic power generation device provided by the present invention is simple, has high production efficiency, has good economy and biocompatibility, and can provide a new sustainable power supply solution for wearable and implantable bioelectronic devices. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 This is a schematic diagram of the working principle of chitosan hydrovoltaic power generation;

[0028] Figure 2 This is a diagram of the composition of a hydrovoltaic power generation device;

[0029] Figure 3 The preparation flow chart of chitosan-citric acid-potassium chloride functional layer:

[0030] Figure 4 Schematic diagram of modular integration scheme of hydroelectric generator devices, where (A) is a schematic diagram of series integration and parallel integration scheme; (B) is a schematic diagram of series-parallel integration (5×6 modules);

[0031] Figure 5 It is a hydroelectric generator unit module, wherein (A) is the output voltage; (B) is the output current;

[0032] Figure 6 It is the series and parallel power control of hydroelectric generator devices;

[0033] Figure 7 The figures are scanning electron microscope images of a hydroelectric generator device, where (A) is an electron microscope image of the surface of the functional layer film; (B) is an electron microscope image of the cross section of the functional layer film. DETAILED DESCRIPTION

[0034] The novel hydroelectric generator device based on the chitosan / citric acid / potassium chloride composite material provided by the present invention has the following working principle:

[0035] After the chitosan / citric acid / potassium chloride functional material layer reacts with water vapor, the water-absorbing groups in the functional material layer, such as carboxyl (-COOH) and protonated amino (-NH 3+ ) can generate charged ions such as H+, and the functional group deprotonates (loses a proton) to form a carboxylate anion (-COO-) or an amino group (-NH2), and the induced proton (H +) diffuses along the concentration gradient inside the electrolyte of the hydrovoltaic power generation device. In addition, moisture or water vapor acts on the functional material layer and ionizes the metal cation K+. Due to the concentration gradient distribution, the carriers diffuse from the higher concentration end to the lower concentration end (i.e., the upper surface → the lower surface); when connected to a pair of electrodes and an external circuit to form a conductive loop, a redox reaction will occur on the electrode surface, and the metal aluminum will be oxidized to trivalent aluminum ions and enter the functional material layer. Due to the concentration gradient, the other cations will migrate in the same direction, and the electrons accumulated on the surface will flow along the external conductive loop to the lower surface, and will interact with the protons H on the positive electrode. + or metal cation Al 3+ , K + The two circuits are combined to generate voltage and current in the external circuit to achieve the output of electrical energy. The working principle is as follows: Figure 1 shown.

[0036] The components of hydrovoltaic power generation devices are as follows: Figure 2 As shown, the hydrovoltaic generator device includes: 1) a PI flexible substrate, 2) an electrode and 3) a chitosan / citric acid / potassium chloride functional film layer. The preparation flow chart of the chitosan / citric acid / potassium chloride functional film layer is as shown in Figure 3 shown.

[0037] The technical solutions provided by the present invention are described in detail below in conjunction with the embodiments, but they should not be construed as limiting the protection scope of the present invention.

[0038] Example 1 Preparation of Hydrovoltaic Generator Device

[0039] Preparation of chitosan / citric acid / potassium chloride functional mixed material dispersion:

[0040] 1) Preparation of citric acid solution. When preparing the citric acid solution, 3 g of citric acid crystals were added to 20 mL of deionized water. Then, the mixture was heated and stirred at a magnetic stirring speed of 400 rpm and a temperature of 50°C. Subsequently, additional deionized water was added to bring the total volume to 30 mL. This resulted in a citric acid solution with a concentration of 100 mg / mL. During this stirring process, the mixture was sealed with a film to prevent evaporation or contamination, and the procedure lasted for about 90 minutes.

[0041] 2) Pretreatment of CS (chitosan) dispersion. A CS dispersion with a concentration of 10 mg / mL was used. In the pretreatment, CS powder was dissolved in citric acid with a concentration of 100 mg / ml so that the mass ratio of CS to CA (citric acid) was 1:10, and stirred at a speed of 400 rpm for 1 hour. During this stirring process, the mixture was sealed with a film to prevent evaporation or contamination, and finally a chitosan hydrogel dispersion was obtained.

[0042] 3) Preparation of potassium chloride (KCl) solution: The KCl concentration was set to 300 mg / ml, the maximum solubility at room temperature, and the stirring speed was 400 rpm, controlled by a magnetic stirrer.

[0043] 4) Preparation of CS / CA / KCl mixture. To prepare the CS / CA / KCl mixture, a certain amount of KCl solution was dropped into the pretreated chitosan dispersion with a concentration of 10 mg / mL, so that the final mass ratio of CS to citric acid to KCl was 1:10:5. The operation was carried out at room temperature, the stirring speed was 400 rpm, and it was controlled by a magnetic stirrer. To ensure the consistency and purity of the stirring process, the beaker was sealed with a film, and the stirring was continued for 90 minutes to obtain a CS / CA / KCl functional layer mixed material dispersion.

[0044] Preparation process of a single module of a hydroelectric generator device:

[0045] The hydroelectric generator device is composed of a flexible PI (Polyimide) substrate, a CS / CA / KCl functional layer and a pair of electrodes. In this embodiment, a gold-plated electrode and an aluminum (Al) electrode are used.

[0046] A PI film washed with deionized water was used as the substrate of the wet gas generator. After drying, a uniform CS / CA / KCl functional layer mixed material dispersion was deposited on the Au bottom electrode (formed on the substrate by a doctor blade pressure coating method) by pipette dispensing or spin coating, and then dried at 80°C for one hour. Finally, an aluminum mesh electrode was placed on the CS / CA / KCl to obtain a hydrovoltaic generator device.

[0047] Example 2 Modular Integration of Hydroelectric Generator Devices - Series Integration

[0048] Each hydrovoltaic generator unit module is connected in series by head-to-tail connection. 1) Paste insulating tape on the designated area of ​​the dry bottom Au electrode on the flexible PI substrate. 2) Then apply chitosan / citric acid / potassium chloride composite material functional layer coating on the designated area above the bottom Au electrode layer by dispensing or spin coating. 3) After the coating is dry, paste insulating tape on the designated area again. 4) Subsequently, use aluminum mesh electrode as the electrode material, and use dispensing or spin coating to establish electrical connection between the top of the chitosan / citric acid / potassium chloride functional layer in a specific area and the bottom electrode of the adjacent unit module. 5) Continue the series connection process of the entire system. This iterative process can realize the series integration of any unit module wet gas generator, such as Figure 4 shown.

[0049] Example 3: Modular Integration of Hydroelectric Generator Devices - Parallel Integration

[0050] The parallel integration of the hydrovoltaic generator system adopts head-to-head and tail-to-tail connection methods for multiple unit modules. 1) Paste insulating tape on the designated area of ​​the dry bottom Au electrode on the flexible PI substrate. 2) Then apply the chitosan / citric acid / potassium chloride composite material functional layer coating on the designated area of ​​the dry bottom Au electrode by dispensing or spin coating. 3) After the coating is dry, paste insulating tape for regional isolation. 4) Finally, make claw-shaped copper wire electrical interconnections at the head or tail end of each unit module. This process can realize the parallel integration of any unit module wet gas generator.

[0051] By combining the above series connection and parallel connection, any unit module hydropower generator can be connected in series and parallel, thus realizing modular integration and expansion of the hydropower generator system. Figure 4 shown.

[0052] The structure of the hydrovoltaic generator device unit module assembly is simple and layered, which is conducive to the modular integration and expansion of the hydrovoltaic power generation system (such as a large-scale hydrovoltaic power generation film or a series-parallel expansion system of multiple hydrovoltaic power generation modules). In addition, the provision of insulating tape can facilitate the system packaging process, which can not only prevent short circuits, but also enhance the output stability of the device.

[0053] Figure 5 The test and characterization results of the hydrovoltaic generator unit module. Under 80% relative humidity conditions, a single hydrovoltaic generator module can output an open circuit voltage of 0.59V ( Figure 5 A), and a peak current of 951μA ( Figure 5 B). The hydroelectric generator system can be modularly expanded according to design requirements.

[0054] The functional units of the hydropower generator device have a simple structure and clear hierarchy, which makes them easy to integrate and expand. Figure 6 a is the test result of series voltage regulation of the hydrovoltaic generator device: through the series integration example of 1 to 15 generator unit modules, a linear and controllable increase in output voltage can be achieved. Figure 6 A is the parallel current control test result of the hydrovoltaic generator device: through the parallel integration example of 1 to 15 generator unit modules, a linear and controllable increase in output current can be achieved. The number of series-parallel units can be adjusted according to the external circuit power requirements (not limited to 15), which can provide flexible electrical output standards and expand the application range of hydrovoltaic generator devices.

[0055] Figure 7 It is the microscopic characterization result of the functional layer of the hydrovoltaic generator. Figure 7A is an electron microscope image of the surface of the hydrovoltaic generator functional layer film. KCl crystals evenly distributed on the surface can be clearly observed. They improve the water absorption capacity of the material. The large amount of charge generated after wetting can increase the overall ion concentration of the material and promote the conduction of current. Figure 7 B is an electron microscope image of the cross-section of the functional layer of the hydrovoltaic generator. The criss-crossing pore structure contributes to the strong capillary action of the material, improving water absorption and enhancing the response speed to water. At the same time, it significantly increases the number of atoms exposed at the edge and the space for active adsorption of water molecules, thereby improving energy conversion efficiency.

[0056] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A chitosan-based hydrovoltaic power generation device, characterized in that: include: Substrate, electrode and chitosan-organic acid-potassium chloride functional layer.

2. The chitosan-based hydrovoltaic power generation device according to claim 1, characterized in that: The chitosan-organic acid-potassium chloride functional layer is prepared by a preparation method comprising the following steps: Mixing a chitosan organic acid hydrogel dispersion and a potassium chloride solution to obtain a functional layer dispersion; The functional layer dispersion is deposited on the electrode and dried to obtain the chitosan-organic acid-potassium chloride functional layer.

3. The chitosan-based hydrovoltaic power generation device according to claim 2, characterized in that: The concentration of the chitosan organic acid hydrogel dispersion is 10 to 30 mg / mL; The concentration of the potassium chloride solution is 250-350 mg / mL.

4. The chitosan-based hydrovoltaic power generation device according to claim 3, characterized in that: The solvent used in the chitosan organic acid hydrogel dispersion is an organic weak acid solution.

5. The chitosan-based hydrovoltaic power generation device according to claim 4, characterized in that: The organic weak acid solution is a citric acid solution; The concentration of the citric acid solution is 50-150 mg / ml.

6. The chitosan-based hydrovoltaic power generation device according to claim 2, characterized in that: The chitosan organic acid hydrogel dispersion and the potassium chloride solution are independently subjected to magnetic stirring before mixing; The rotation speed of the magnetic stirring is 300-500 rpm.

7. The chitosan-based hydrovoltaic power generation device according to claim 2, characterized in that: The total mixing time is 60 to 120 minutes.

8. The chitosan-based hydrovoltaic power generation device according to claim 2, characterized in that: The deposition onto the electrode is carried out by dispensing or spin coating; The substrate adopts a flexible PI substrate; The electrodes include gold-plated electrodes and aluminum electrodes.

9. A hydroelectric generator system, characterized in that: The invention comprises a plurality of chitosan-based hydrovoltaic power generation devices according to any one of claims 1 to 8 integrated in series.

10. A hydroelectric generator system, characterized in that: The invention comprises a plurality of chitosan-based hydrovoltaic power generation devices according to any one of claims 1 to 8 integrated in parallel.

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