Light collection device based on ionic gelatin hydrogel liquid drops as well as preparation method and application of light collection device

Abstract

The invention discloses a light collection device based on ionic gelatin hydrogel liquid drops and a preparation method and application thereof, and relates to the technical field of light collection, the light collection device comprises an electrode module and a gelatin hydrogel functional layer which are sequentially arranged on a substrate module; the substrate module is a substrate sheet, and the substrate sheet is any one of a flexible substrate sheet and a rigid substrate sheet; the electrode modules are metal electrodes arranged on the two sides of the gelatin hydrogel functional layer; the gelatin hydrogel functional layer comprises common hydrogel liquid drops and light response hydrogel liquid drops. The light collection device can be prepared only through a simple drop casting method, can be used for collecting and converting various clean energy sources, achieves light collection, supports manufacturing of units of any size or shape, has the advantage of being simple in system, still has the output capacity after illumination is removed, and solves the problems that a traditional light collection device is complex in structure and low in cost. The biocompatibility is poor, and the like.

Description

Technical Field

[0001] The present invention relates to the field of light collection technology, and in particular to a light collection device based on ionic gelatin hydrogel droplets, a preparation method and an application thereof. Background Art

[0002] Energy harvesting technology offers a promising alternative to conventional continuous energy conversion and storage, and is closely related to the strategic goal of sustainable energy development. Light harvesting devices that collect ambient light can power electronic devices, soft robots, and smart IoT sensors without the need for wired connections or battery replacement. Ideally, energy harvesting devices should combine biocompatibility, mechanical flexibility, and efficient energy conversion and storage. However, current light harvesting devices are mainly based on solid or liquid systems, in which separate conversion and storage modules are integrated. This integration not only limits compatibility and space utilization, but also increases manufacturing, maintenance, and repair costs due to the complexity of combining multiple components. Therefore, it is challenging to develop flexible, biocompatible devices suitable for various applications.

[0003] In summary, how to propose a flexible, biocompatible light collection device and preparation method that can collect light and convert it into electrical output and has a simple structure has become an important issue that needs to be urgently addressed in the industry. Summary of the Invention

[0004] The purpose of the present invention is to provide a light-collecting device based on ionic gelatin hydrogel droplets, its preparation method and application, to solve the above-mentioned problems. The prepared light-collecting device has the characteristics of simple structure, low cost, good biocompatibility and the ability to convert light collection into electrical output.

[0005] The present invention discloses a light collecting device based on ionic gelatin hydrogel droplets, comprising an electrode module and a gelatin hydrogel functional layer sequentially arranged on a base module;

[0006] The base module is a base sheet, and the base sheet is either a flexible base sheet or a rigid base sheet;

[0007] The electrode module is a metal electrode arranged on both sides of the gelatin hydrogel functional layer;

[0008] The gelatin hydrogel functional layer includes ordinary hydrogel droplets and light-responsive hydrogel droplets.

[0009] The present invention also provides a method for preparing the above-mentioned light collecting device, comprising the following steps:

[0010] S1. Clean the substrate with deionized water and modify its surface using a plasma cleaner;

[0011] S2. Depositing a metal film on a substrate using a coating technique or attaching a commercial metal sheet to a substrate to serve as a metal electrode, with a gap left between the two metal electrodes for subsequent drop casting of hydrogel droplets;

[0012] S3, mixing the gelatin material with deionized water and an alcohol material, and dissolving them to obtain a common hydrogel droplet dispersion P1; mixing the gelatin material with deionized water, a photoresponsive material, and an alcohol material, and dissolving them to obtain a photoresponsive hydrogel droplet dispersion P2;

[0013] S4: Drop-casting the ordinary hydrogel droplet dispersion P1 and the photoresponsive hydrogel droplet dispersion P2 respectively into the gap between the two metal electrodes on the substrate, ensuring that the two droplets are in contact with the electrodes on both sides and the middle interfaces of the two droplets are also in contact with each other; after the drop-casting is completed, the mixture is allowed to stand at room temperature;

[0014] S5: Wires are configured for the two metal electrodes respectively, and finally a light collection device based on ionic gelatin hydrogel droplets is obtained.

[0015] Preferably, in step S1, the substrate sheet includes but is not limited to flexible polyethylene terephthalate or rigid glass.

[0016] Preferably, in step S2, the metal electrodes include but are not limited to gold, copper, platinum, silver, and zinc, and the coating technology includes but is not limited to magnetron sputtering technology and thermal evaporation technology; a gap with a length of 5mm-40mm is retained in the middle of the metal electrodes.

[0017] Preferably, a gap with a length of 10 mm is retained in the middle of the metal electrode.

[0018] Preferably, in step S3, in the common hydrogel droplet dispersion P1, the mass ratio of gelatin material, deionized water, and alcohol material is (1-3):10:(2-8), wherein the alcohol material includes but is not limited to one of ethylene glycol, glycerol, and ethanol;

[0019] In the photoresponsive hydrogel droplet dispersion P2, the mass ratio of gelatin material, deionized water, photoresponsive material and alcohol material is (1-3):10:(0.2-0.8):(2-8).

[0020] Preferably, in step S3, in the ordinary hydrogel droplet dispersion P1, the mass ratio of gelatin material, deionized water, and alcohol material is 1.5:10:5, and in the photoresponsive hydrogel droplet dispersion P2, the mass ratio of gelatin material, deionized water, photoresponsive material, and alcohol material is 1.5:10:0.5:5.

[0021] Preferably, the photoresponsive material includes but is not limited to ammonium molybdate material, tungstic acid material, ammonium tungstate material and one of other polyoxometalate materials, and the polyol material includes but is not limited to one of ethylene glycol, glycerol and ethanol; the dissolution temperature is 40°C-50°C, and the heating method is a water bath.

[0022] Preferably, in step S4, the patterns of the P1 and P2 droplets when cast include but are not limited to square and circle, and their sizes may be symmetrically the same or different, and the standing time is 10 min-20 min.

[0023] Preferably, in step S5, the wires configured as the metal electrodes are copper wires.

[0024] The present invention provides a light collection device based on ionic gelatin hydrogel droplets, which undergoes a photochemical reaction under excitation light, has voltage output performance, and maintains the voltage after the light is removed. The device is used in the fields of light collection, biomedicine, and flexible electronics.

[0025] Therefore, the present invention adopts the above-mentioned light collection device based on ionic gelatin hydrogel droplets and its preparation method and application, which has the following beneficial effects:

[0026] The gelatin hydrogel functional layer of the present invention comprises two-component droplets. Conventional gelatin hydrogel droplets maintain the system's photostability, while photoresponsive hydrogel droplets, upon light excitation, alter the surrounding charged particle concentration and redox potential. Consequently, when excited, an ion concentration gradient is generated between the conventional and photoresponsive hydrogel droplets, ensuring ion diffusion and biocompatibility. This change in redox potential leads to a change in the counter electrode potential. Consequently, the combined effects of the ion concentration gradient and the redox pair generate a voltage across the electrodes or a current in the circuit. During the energy conversion process, light energy is first converted into chemical energy and then into electrical energy via the electrodes' capacitive storage mechanism. This highlights the potential of ions as carriers for converting and storing ambient light energy. Furthermore, the prepared material exhibits excellent flexibility and toughness. The hydrogel droplets exhibit liquid-like properties at 45 degrees Celsius and spontaneously form a stable three-dimensional hydrogel network at room temperature over a short period of time. This phase change process has good thermal reversibility, and the supporting power generation device adopts a simple structural design. The device assembly can be achieved through a convenient drop casting process, showing broad application potential in the fields of energy harvesting and bioelectronic devices.

[0027] The photoelectric power generation device constructed based on ionic gelatin hydrogel droplets described in the present invention can achieve a steady-state voltage output of the order of 250mV under light excitation conditions, and can still maintain a significant residual potential response one hour after the light is terminated. At the same time, because the rheological properties of the hydrogel droplets show unique advantages and support the construction of units of arbitrary geometric configurations, when the characteristic dimensions of the device are proportionally reduced by dozens of times, its open-circuit voltage output characteristics can still be stably maintained at a baseline level of 250mV. The linear superposition of output performance can be achieved by adopting basic series and parallel combinations, providing a feasible technical path for the construction of large-scale energy harvesting arrays.

[0028] The technical solution of the present invention is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 This is a schematic structural diagram of a light collection device based on ionic gelatin hydrogel droplets of the present invention;

[0030] Figure 2 This is a physical picture of the light collection device based on ionic gelatin hydrogel droplets in Example 1 of the present invention;

[0031] Figure 3 1. Actual images of liquid and solidified states of ordinary hydrogel droplets and light-responsive hydrogel droplets in a light-collecting device based on ionic gelatin hydrogel droplets in Example 1 of the present invention;

[0032] Figure 4 This is a performance diagram of the light-excitation voltage output test of the light-collecting device based on ionic gelatin hydrogel droplets prepared in Example and Example 2 of the present invention using different electrodes;

[0033] Figure 5 Graphs showing the light excitation voltage output performance of light collection devices based on ionic gelatin hydrogel droplets prepared in Examples 1, 3, and 4 of the present invention at different volume sizes;

[0034] Figure 6 This is a diagram showing the application of the light collection device based on ionic gelatin hydrogel droplets prepared in Example 1 of the present invention for repairing epidermal wounds in organisms;

[0035] Reference numerals:

[0036] 1. First metal electrode; 2. Second metal electrode; 3. Ordinary gelatin hydrogel droplets; 4. Photoresponsive gelatin hydrogel droplets; 5. Base sheet. DETAILED DESCRIPTION

[0037] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the following will refer to the accompanying drawings of the embodiments of the present invention. Figures 1 to 6The technical solutions of the present invention are clearly and completely described. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts are within the scope of protection of the present invention.

[0038] In the description of the present invention, it should be understood that the terms "center", "surroundings", "horizontal", "longitudinal", "length", "thickness", "angle", "up", "down", "left", "right", etc., which indicate directions or positions, are limited to simplifying the description of the present invention, rather than specific positions or directions. The above terms are not limitations of the present invention.

[0039] The present invention discloses a light collecting device based on ionic gelatin hydrogel droplets, comprising an electrode module and a gelatin hydrogel functional layer sequentially arranged in a base module; the base module is a base sheet, which is either a flexible base sheet or a rigid base sheet; the electrode module is a metal electrode arranged on both sides of the gelatin hydrogel functional layer.

[0040] The gelatin hydrogel functional layer includes ordinary hydrogel droplets and photoresponsive hydrogel droplets.

[0041] The present invention also provides a method for preparing the above-mentioned light collecting device, comprising the following steps:

[0042] S1. Clean the substrate with deionized water and modify its surface using a plasma cleaner.

[0043] S2. Use coating technology to deposit a metal film on the substrate or attach a commercial metal sheet to the substrate to serve as a metal electrode, leaving a gap between the two metal electrodes for subsequent drop casting of hydrogel droplets.

[0044] S3. Mix the gelatin material with deionized water and an alcohol material, and dissolve them to obtain a common hydrogel droplet dispersion P1; mix the gelatin material with deionized water, a photoresponsive material, and an alcohol material, and dissolve them to obtain a photoresponsive hydrogel droplet dispersion P2.

[0045] S4: Drop-cast the ordinary hydrogel droplet dispersion P1 and the photoresponsive hydrogel droplet dispersion P2 respectively in the gap between the two metal electrodes on the substrate, ensuring that the two droplets are in contact with the electrodes on both sides and the middle interfaces of the two droplets are also in contact with each other; after the drop-casting is completed, let it stand at room temperature.

[0046] S5: Wires are configured for the two metal electrodes respectively, and finally a light collection device based on ionic gelatin hydrogel droplets is obtained.

[0047] Wherein; in step S1, the substrate sheet includes but is not limited to flexible polyethylene terephthalate or rigid glass.

[0048] In step S2, the metal electrodes include but are not limited to gold, copper, platinum, silver, and zinc, and the coating technology includes but is not limited to magnetron sputtering technology and thermal evaporation technology; a gap with a length of 5mm-40mm is retained in the middle of the metal electrode, among which the effect is better when the gap length is 10mm.

[0049] In step S3, in the ordinary hydrogel droplet dispersion P1, the mass ratio of gelatin material, deionized water, and alcohol material is (1-3):10:(2-8). When the ratio is 1.5:10:5, the effect is better; wherein the alcohol material includes but is not limited to one of ethylene glycol, glycerol, and ethanol.

[0050] In the photoresponsive hydrogel droplet dispersion P2, the masses of gelatin material, deionized water, photoresponsive material and alcohol material are (1-3):10:(0.2-0.8):(2-8). When the ratio is 1.5:10:0.5:5, the effect is better.

[0051] The photoresponsive material includes but is not limited to ammonium molybdate material, tungstic acid material, ammonium tungstate material and one of other polyoxometalate materials; the polyol material includes but is not limited to one of ethylene glycol, glycerol and ethanol; the dissolution temperature is 40°C-50°C, and the heating method is a water bath.

[0052] In step S4, the patterns of the P1 and P2 droplets when cast include but are not limited to square and circle, and their sizes may be symmetrical, identical or different, and the standing time is 10-20 minutes.

[0053] In step S5 , the wires configured as the metal electrodes are copper wires.

[0054] The present invention provides a light collection device based on ionic gelatin hydrogel droplets, which undergoes a photochemical reaction under excitation light, has voltage output performance, and maintains the voltage after the light is removed. The device is used in the fields of light collection, biomedicine, and flexible electronics.

[0055] The following will be combined with the accompanying drawings of the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Generally, the various components of the embodiments of the present invention described and shown in the drawings herein can be configured and designed with a variety of similar materials. The specific ratio of the metal electrode and the hydrogel functional layer materials needs to be optimized based on the materials used in the device. The specific metal electrode preparation method adopts the existing magnetron sputtering technology in the field, so it will not be described in detail.

[0056] Example 1

[0057] This embodiment provides a light collection device based on ionic gelatin hydrogel droplets, the preparation method of which includes the following steps:

[0058] S1: Clean the commercial flexible polyethylene terephthalate substrate with deionized water and perform surface modification in an air atmosphere using a plasma cleaner for 2 minutes to ensure enhanced bonding with the subsequent magnetron sputtered metal electrode.

[0059] S2: A gold thin film was sputter-deposited onto the substrate using magnetron sputtering technology to serve as the metal electrode. Sputtering conditions included an argon atmosphere with a pressure of 0.2 Pa and a DC power of 5 W for 5 minutes. A 10 mm gap was maintained between the two metal electrodes to allow for subsequent hydrogel droplet casting.

[0060] S3: The gelatin material was mixed with deionized water and ethylene glycol materials in a mixing mass ratio of 1.5:10:5, and dissolved at 45°C to obtain a normal hydrogel droplet dispersion P1; the gelatin material was mixed with deionized water, ammonium molybdate material and ethylene glycol material in a mixing mass ratio of 1.5:10:0.5:5, and dissolved at 45°C to obtain a photoresponsive hydrogel droplet dispersion P2.

[0061] S4: Ordinary hydrogel droplet dispersion P1 and photoresponsive hydrogel droplet dispersion P2 are drop-casted in the gap between the two metal electrodes on the substrate, ensuring that the two droplets are in contact with the gold electrodes on both sides, and the middle interfaces of the two droplets are also in contact with each other; after the two droplets are drop-casted, they are left to stand at room temperature for 15 minutes, and the effective volume of the hydrogel functional layer is 10mm×10mm×2mm.

[0062] S5: After the above steps, a light-collecting device based on ionic gelatin hydrogel droplets is finally obtained. Copper wires are configured for each metal electrode for performance testing.

[0063] like Figure 1 As shown, the light collection device based on ionic gelatin hydrogel droplets in this embodiment is sequentially configured with a substrate module, an electrode module, and a gelatin hydrogel functional layer module. The substrate module is a substrate sheet 5. In this embodiment, substrate sheet 5 is a commercially available flexible polyethylene terephthalate substrate, which provides a support for the placement and assembly of the electrodes and gelatin hydrogel functional layer. The electrode module comprises a first metal electrode 1 and a second metal electrode 2, fabricated on substrate sheet 5 by magnetron sputtering. These two metal electrodes are identical, and in this embodiment, are made of gold. They are used to convert the changes in charged particles generated by the light-induced changes in the hydrogel droplets into electrical output.

[0064] The gelatin hydrogel functional module includes conventional gelatin hydrogel droplets 3 and photoresponsive gelatin hydrogel droplets 4. Conventional gelatin hydrogel droplets are photostable, while photoresponsive hydrogel droplets, when stimulated by light, alter the concentration of surrounding charged particles and their redox potential. Consequently, when stimulated, an ion concentration gradient is generated between the conventional and photoresponsive hydrogel droplets. This shift in redox potential also alters the counter electrode potential, generating a voltage between the two metal electrodes.

[0065] Figure 2 This is a practical picture of the light collection device based on ionic gelatin hydrogel droplets in this embodiment. Figure 3 The following are the actual pictures of the liquid and solidified states of ordinary hydrogel droplets and light-responsive hydrogel droplets in the light collection device based on ionic gelatin hydrogel droplets in this embodiment. Figure 2 As shown, the hydrogel droplet light collection device provided by the present invention includes a substrate, a metal electrode and a gelatin hydrogel functional layer.

[0066] The metal electrodes on the substrate are obtained by magnetron sputtering technology, and a certain gap is retained in the middle for the subsequent drop casting of hydrogel droplets. The gelatin hydrogel functional layer includes ordinary gelatin hydrogel droplets and photoresponsive gelatin hydrogel droplets. These two types of hydrogel droplets have flexible transition temperatures and are liquid at 45°C. After about 15 minutes at room temperature, a stable hydrogel network can be formed. Figure 3 As shown. Therefore, the drop casting method can be used to assemble light-collecting devices simply and flexibly. When the hydrogel light-collecting device is excited by the excitation light field, the ammonium molybdate material in the photoresponsive hydrogel droplets undergoes a photochemical process under light excitation, generating negatively charged particles. Ordinary gelatin hydrogel droplets are photostable, so an ion concentration difference is formed between the two hydrogel droplets. The valence state of the molybdenum element changes, causing the redox potential of the counter electrode to change. Therefore, under the combined action of the ion concentration difference and the redox potential of the counter electrode, a voltage output is generated on both sides of the metal electrode.

[0067] Example 2

[0068] This embodiment provides a preparation method for a light collecting device based on ionic gelatin hydrogel droplets, which is the same as the preparation method in Example 1, except that the metal electrode deposited in step S2 is made of copper, and the sputtering conditions are to adjust the working gas pressure to 0.0005 Pa in an argon atmosphere, followed by sputtering for 20 minutes at a DC power of 40 W.

[0069] Example 3

[0070] This embodiment provides a method for preparing a light collecting device based on ionic gelatin hydrogel droplets, which is the same as the preparation method in Example 1, except that the effective volume of the hydrogel functional layer in step S4 is 5 mm×1 mm×2 mm.

[0071] Example 4

[0072] This embodiment provides a method for preparing a light collecting device based on ionic gelatin hydrogel droplets, which is the same as the preparation method in Example 1, except that the effective volume of the hydrogel functional layer in step S4 is 20 mm × 20 mm × 2 mm.

[0073] Figure 4 The light collection device based on ionic gelatin hydrogel droplets prepared in Example 1 and Example 2 uses the light excitation voltage output test performance diagram under different electrodes (the light excitation power density is 5.7mW / cm 2 , wavelength is 365nm); Figure 5 The light excitation voltage output test performance diagram of the light collection device based on ionic gelatin hydrogel droplets prepared in Examples 1, 3-4 of the present invention at different volume sizes (the light excitation power density is 5.7mW / cm 2 , wavelength is 365nm). Figure 4 As shown in the figure, after the voltage of the device reaches a steady state when the excitation light is applied, the gold electrode device in Example 1 can generate an output voltage of 250mV, and the copper electrode device in Example 2 can generate an output voltage of 80mV. It should be noted that due to the ion diffusion and oxidation-reduction changes in the hydrogel functional layer, it still has a voltage output within 1 hour after the light is removed. Figure 5 The results show that flexible hydrogel droplets can be used to make units of any volume, and their output performance remains at 250mV even when the device size differs eighty times.

[0074] In addition, the performance of the light collecting device can be further improved by simple series and parallel connection, and it can be used as a bioelectronic device. The output power can be used to repair the skin damage of the organism, such as Figure 6 As shown, the ionic gelatin hydrogel droplet light collecting device prepared in Example 1 was placed above the damaged biological epidermis. The results showed that compared with the control group using medical gauze, the damaged biological epidermis covered with the light collecting device repaired faster, and the edges were smooth after repair, with almost no damage outline.

[0075] Therefore, the present invention proposes a light collection device based on ionic gelatin hydrogel droplets and a preparation method thereof, which combines gelatin hydrogel materials and light-responsive materials. The light collection device can be realized through simple and flexible hydrogel droplet casting assembly, has the advantages of energy conversion, good biocompatibility and system simplicity, can realize light collection and support the manufacture of units of any size or shape, solving the difficulties of traditional light collection devices such as complex system, high cost and poor biocompatibility.

[0076] The specific implementation methods described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific implementation method of the present invention and does not limit the scope of protection of the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A light collection device based on ionic gelatin hydrogel droplets, characterized in that: It includes an electrode module and a gelatin hydrogel functional layer sequentially arranged on a base module; The base module is a base sheet, and the base sheet is either a flexible base sheet or a rigid base sheet; The electrode module is a metal electrode arranged on both sides of the gelatin hydrogel functional layer; The gelatin hydrogel functional layer includes ordinary hydrogel droplets and light-responsive hydrogel droplets.

2. The method for preparing a light collecting device based on ionic gelatin hydrogel droplets according to claim 1, characterized in that: The following steps are involved: S1. Clean the substrate with deionized water and modify its surface using a plasma cleaner; S2. Depositing a metal film on the substrate using a coating technique or attaching a metal sheet to the substrate to serve as a metal electrode, with a gap left between the two metal electrodes for subsequent drop casting of hydrogel droplets; S3, mixing the gelatin material with deionized water and an alcohol material, and dissolving them to obtain a common hydrogel droplet dispersion P1; mixing the gelatin material with deionized water, a photoresponsive material, and an alcohol material, and dissolving them to obtain a photoresponsive hydrogel droplet dispersion P2; S4: Drop-casting the ordinary hydrogel droplet dispersion P1 and the photoresponsive hydrogel droplet dispersion P2 respectively into the gap between the two metal electrodes on the substrate, ensuring that the two droplets are in contact with the electrodes on both sides and the middle interfaces of the two droplets are also in contact with each other; after the drop-casting is completed, the mixture is allowed to stand at room temperature; S5: Wires are configured for the two metal electrodes respectively, and finally a light collection device based on ionic gelatin hydrogel droplets is obtained.

3. The method for preparing a light collecting device based on ionic gelatin hydrogel droplets according to claim 2, characterized in that: In step S1 , the substrate is made of either flexible polyethylene terephthalate or rigid glass.

4. The method for preparing a light collecting device based on ionic gelatin hydrogel droplets according to claim 2, characterized in that: In step S2, the metal electrode is any one of gold, copper, platinum, silver, and zinc, and a gap with a length of 5 mm to 40 mm is retained in the middle of the metal electrode.

5. The method for preparing a light collecting device based on ionic gelatin hydrogel droplets according to claim 2, characterized in that: In step S3, in the common hydrogel droplet dispersion P1, the mass ratio of gelatin material, deionized water, and alcohol material is (1-3):10:(2-8), wherein the alcohol material is any one of ethylene glycol, glycerol, and ethanol; In the photoresponsive hydrogel droplet dispersion P2, the mass ratio of gelatin material, deionized water, photoresponsive material and alcohol material is (1-3):10:(0.2-0.8):(2-8).

6. The method for preparing a light collecting device based on ionic gelatin hydrogel droplets according to claim 2, characterized in that: The light-responsive material is any one of ammonium acid material, tungstic acid material, ammonium tungstate material and polyoxometalate material other than ammonium and tungsten metal; the polyol material is any one of ethylene glycol, glycerol and ethanol; the dissolution temperature is 40°C-50°C, and the heating method is a water bath.

7. The method for preparing a light collecting device based on ionic gelatin hydrogel droplets according to claim 2, wherein in step S4, the standing time is 10 min to 20 min.

8. The method for preparing a light collecting device based on ionic gelatin hydrogel droplets according to claim 2, wherein in step S5, the wires configured as the metal electrodes are copper wires.

9. The use of a light collecting device based on ionic gelatin hydrogel droplets according to claim 1, characterized in that: The light collection device undergoes a photochemical reaction under excitation light, has a voltage output performance, and maintains the voltage after the light is removed. It is used in the fields of light collection, biomedicine, and flexible electronics.

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