A rechargeable and dischargeable battery and a photorechargeable battery based on bismuth element material

Abstract

The present invention relates to a rechargeable and dischargeable battery and a photorechargeable battery based on bismuth material, which sequentially comprises an FTO conductive substrate, an electron transport layer, a photoelectric active layer based on Bi, and a platinum or carbon counter electrode. The electron transport layer is composed of a dense layer of porous oxide and a mesoporous layer of porous oxide, and the porous oxide is TiO2, SnO2, ZnO or Sb2O5. The rechargeable and dischargeable battery can be charged using sunlight, converting light energy into electrical energy for storage, and powering electrical devices in the dark state. The present invention expands the electroactive material system of secondary batteries and provides a solid-state two-electrode photorechargeable battery device, which will greatly promote the practical application of photorechargeable battery devices.

Description

Technical Field

[0001] The present invention belongs to the field of new energy and energy-saving technology, and specifically relates to a rechargeable and dischargeable battery and a photorechargeable battery based on bismuth element material. Background Art

[0002] Solar energy is an important source of renewable energy. Due to the fluctuations and discontinuities in sunlight intensity, solar cells must be coupled with energy storage devices to provide a continuous, uninterrupted power supply. Currently, three strategies exist for connecting solar cells to energy storage devices: wire connection (four-electrode system), three-electrode integrated system, and two-electrode system. The combination of solar cells and rechargeable batteries is typically achieved by externally connecting two separate devices, such as in space solar power plants and solar rooftop power systems. These systems require additional circuitry and electronic components to overcome the mismatch between the energy harvesting unit and the energy storage device. Furthermore, such systems are large, heavy, and expensive. Another integration technique combines solar cells and rechargeable batteries in a single device. This can be achieved using dual-function electrodes that can both harvest and store solar energy, similar to a battery (three-electrode integration). Three-electrode integration can address some of the issues associated with four-electrode systems. However, three-electrode integrated systems have complex structures and a complex relationship between light absorption and energy storage properties. Compared with four-electrode and three-electrode systems, two-electrode photorechargeable batteries are the most attractive integration strategy due to their simple, compact, high-quality, and flexible fabrication process and the possibility of commercial production.

[0003] Based on this, the present invention proposes a rechargeable and dischargeable battery and a photorechargeable battery based on bismuth. This rechargeable and discharge battery can be charged using sunlight, converting light energy into stored electrical energy, and then powering electrical devices in the dark. This invention expands the electroactive material system of secondary batteries and provides a solid-state two-electrode photorechargeable battery device, which will greatly promote the practical application of photorechargeable battery devices. Summary of the Invention

[0004] The present invention aims to overcome the defects of the prior art and provide a rechargeable and dischargeable battery and a photorechargeable battery based on bismuth element materials.

[0005] The present invention also provides a method for preparing the above-mentioned rechargeable and dischargeable battery and photorechargeable battery based on bismuth element material.

[0006] To achieve the above object, the present invention adopts the following technical solutions:

[0007] A rechargeable and dischargeable battery and a photorechargeable battery based on bismuth material adopt a typical sandwich structure system. The battery structure includes an FTO conductive substrate, an electron transport layer, a photoelectric active layer based on Bi element, and a platinum or carbon counter electrode. Figure 1 shown.

[0008] The above-mentioned rechargeable and dischargeable battery and photorechargeable battery, further, the electron transport layer is composed of a porous oxide dense layer and a porous oxide mesoporous layer, and the porous oxide is an n-type porous oxide such as TiO2, SnO2, ZnO or Sb2O5.

[0009] The present invention provides a method for preparing the above-mentioned rechargeable and dischargeable battery and photorechargeable battery based on bismuth element material, which comprises the following steps:

[0010] 1) Pretreatment of FTO conductive substrate;

[0011] 2) Preparation of electron transport layer;

[0012] 3) Preparation of a Bi-based photoelectric active layer: CsI and BiI3 are dissolved in a mixed solvent of DMF and DMSO at a certain molar ratio to prepare a precursor solution with a BiI3 concentration of 0.2-0.7 M. An appropriate amount of HI is then added and the reaction is stirred for 20-30 hours to obtain a photoelectric active layer solution. The photoelectric active layer solution is then dripped onto the electron transport layer to cover the entire surface of the electron transport layer.

[0013] 4) Preparation of platinum or carbon counter electrode;

[0014] 5) Hot-press the platinum or carbon counter electrode obtained in step 4) onto the photoelectric active layer obtained in step 3) at 80-110°C. Then, anneal it on a hotplate at 85-95°C for 3-10 minutes. Then, raise the temperature to 100-110°C and anneal it for 3-10 minutes. The platinum or carbon counter electrode and electron transport layer in the prepared battery device are then connected with wires for testing of photoelectric performance and charge-discharge performance.

[0015] Specifically, in step 3), the molar ratio of CsI to BiI3 is 1:1-3, and the amount of HI added is 4-6% of the volume of the mixed solvent.

[0016] Furthermore, the volume ratio of N,N-dimethylformamide (DMF) to dimethyl sulfoxide (DMSO) is 4:1-2, preferably 4:1.

[0017] Furthermore, the pretreatment of the FTO conductive substrate in step 1) is specifically as follows: the FTO conductive substrate is first ultrasonically cleaned with detergent, anhydrous ethanol, isopropyl alcohol, and deionized water in sequence, dried, and then placed in a plasma cleaning machine for cleaning at room temperature to remove residual organic impurities.

[0018] Specifically, the preparation of the electron transport layer in step 2) consists of the preparation of a TiO2 dense layer and the preparation of a TiO2 mesoporous layer;

[0019] The TiO2 dense layer is prepared by dissolving 5 mL of isopropyl titanate in 15-20 mL of n-butanol to obtain a dense layer precursor solution, coating the dense layer precursor solution on a pretreated clean FTO conductive substrate (spin coating speed of 2000 ± 500 rpm), and then sintering in a muffle furnace at 450-500°C for 0.5-1.5h to obtain the obtained product.

[0020] The preparation of the TiO2 mesoporous layer is specifically as follows: 1g of titanium dioxide P25 powder is evenly mixed with 10-20mL of n-butanol and 0.1-0.2ml of Triton X-100 (used to increase the viscosity of the solution) to obtain a mesoporous layer slurry; the mesoporous layer slurry is then dropped onto the TiO2 dense layer, and the mesoporous layer slurry is evenly scraped using a scraping rod (the thickness is generally 5-15 microns), naturally dried in a clean bench, and then sintered in a muffle furnace at 450-500°C for 0.5-1.5h to obtain the obtained layer.

[0021] Furthermore, the preparation of the platinum counter electrode in step 4) is specifically as follows: chloroplatinic acid (H 14 C 16 O6Pt) is dissolved in isopropyl alcohol to prepare a 0.004-0.010M chloroplatinic acid solution. The chloroplatinic acid solution is then drop-coated on a pretreated clean FTO conductive substrate in an environment with an air humidity of 15-25%. After natural drying, it is sintered in a muffle furnace at 360-420°C for 15-40 minutes. Repeat the above operation multiple times to form a metallic, uniform, and agglomerated platinum metal film on the FTO conductive substrate. The thickness is generally 0.8-2 microns.

[0022] Furthermore, the preparation of the carbon counter electrode described in step 4) is specifically as follows: 0.2g PVDF (polyvinylidene fluoride) powder is mixed with 10-20ml isopropyl alcohol, 0.2-0.3g titanium dioxide P25 powder, 0.4-0.6g carbon black powder and 2-6mL N-methylpyrrolidone to obtain a carbon slurry; the carbon slurry is then dropped onto a pretreated clean FTO conductive substrate, and is scraped with a scraper bar. After natural drying, the carbon slurry is dried in a drying oven at 60-80°C for 15-30 minutes to produce a flat carbon electrode film on the FTO conductive substrate.

[0023] The theoretical basis of the present invention is as follows:

[0024] 1) The battery charging process is B 3+Reduction to low-valent bismuth ions or zero-valent bismuth atoms, the discharge process is the oxidation of low-valent bismuth ions or zero-valent bismuth atoms to B 3+ ion;

[0025] 2) The photocharging and discharging process of the battery is that sunlight excites the bismuth-based photoactive material, the photogenerated charges are separated, and the photogenerated electrons promote B 3+ Reduction to low-valent bismuth ions or zero-valent bismuth atoms, converting solar energy into electrical energy and storing it in the battery. In the dark state, low-valent bismuth ions or zero-valent bismuth atoms are converted into B 3+ , releasing electrons and supplying power to the external circuit through the electron collection layer.

[0026] Compared with the prior art, the present invention has the following beneficial effects:

[0027] The present invention provides a novel rechargeable and dischargeable battery and a photorechargeable battery based on bismuth-based materials. The research and development of novel electroactive materials for secondary batteries has long been a key area of ​​energy research and development. This invention proposes a bismuth-based electroactive material, proposes its possible charge and discharge processes, and designs a rechargeable and dischargeable battery structure, broadening the candidate pool of electroactive materials for secondary batteries. Furthermore, a photorechargeable battery based on this material is proposed, potentially enabling the practical application of photorechargeable secondary batteries. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 Schematic diagram of the structure of the battery of the present invention (FTO conductive substrate / electron transport layer / photoelectric active layer / counter electrode);

[0029] Figure 2 FTO / TiO2 / Cs3Bi2I9 / Pt / FTO (n CsI :n BiI3 =1:2) JV curve of battery device;

[0030] Figure 3 Statistical graph of open circuit voltage of FTO / TiO2 / Cs3Bi2I9 / Pt / FTO battery device prepared in Example 1 under light and dark state;

[0031] Figure 4 This is a photo of 30 FTO / TiO2 / Cs3Bi2I9 / Pt / FTO battery devices prepared in Example 1 connected in series after photocharging, lighting up an LED lamp in the dark state;

[0032] Figure 5 This is a graph showing the working time of the LED and the lighting time of the battery after 30 FTO / TiO2 / Cs3Bi2I9 / Pt / FTO battery devices prepared in Example 1 are connected in series after photocharging in the dark state;

[0033] Figure 6FTO / TiO2 / Cs3Bi2I9 / Pt / FTO (n CsI :n BiI3 =1:1, 1:3) JV curve of battery device;

[0034] Figure 7 This is a JV curve of the FTO / TiO2 / Cs3Bi2I9 / C / FTO battery device prepared in Example 4;

[0035] Figure 8 This is a charge and discharge curve diagram of the FTO / TiO2 / Cs3Bi2I9 / Pt / FTO battery device prepared in Example 1;

[0036] Figure 9 This is a charge and discharge cycle test curve of the FTO / TiO2 / Cs3Bi2I9 / Pt / FTO battery device prepared in Example 1. DETAILED DESCRIPTION

[0037] The technical solution of the present invention is further described in detail below in conjunction with the embodiments, but the protection scope of the present invention is not limited thereto.

[0038] In the following examples, unless otherwise specified, all raw materials used are commercially available products that can be directly purchased. Room temperature refers to 25±5°C.

[0039] Example 1

[0040] A rechargeable and dischargeable battery and a photorechargeable battery based on bismuth material, wherein the battery structure includes an FTO conductive substrate, an electron transport layer composed of a TiO2 dense layer and a TiO2 mesoporous layer, a photoelectric active layer based on the Bi element, and a platinum counter electrode, recorded as FTO / TiO2 / Cs3Bi2I9 / Pt / FTO.

[0041] The preparation method of the above-mentioned FTO / TiO2 / Cs3Bi2I9 / Pt / FTO battery device comprises the following steps:

[0042] 1) Pretreatment and cleaning of FTO conductive substrate: ultrasonically clean the FTO glass with detergent, anhydrous ethanol, isopropyl alcohol, and deionized water for 15 minutes each, dry it, and then place it in a plasma cleaner at room temperature for 15 minutes to remove residual organic impurities;

[0043] 2) Preparation of a TiO2 dense layer: 5 mL of isopropyl titanate was added to 15 mL of n-butanol, sealed, and stirred on a magnetic stirrer for 1 hour to fully dissolve the solution to obtain a dense layer precursor solution. A certain amount of this dense layer precursor solution was then applied to a clean, pre-cleaned FTO substrate at a spin coating speed of 2000 rpm for 60 seconds. The solution was then sintered in a muffle furnace at 450°C for 30 minutes to obtain a TiO2 dense layer.

[0044] 3) Preparation of TiO2 mesoporous layer: Weigh 1g of titanium dioxide P25 powder and pour it into a volumetric flask containing 10mL of n-butanol. Add 0.1ml of Triton X-100 to increase the viscosity of the solution. After sealing, ultrasonicate in an ultrasonic cleaner for 15 minutes, and then stir on a magnetic stirrer for 10 hours to mix evenly to obtain a mesoporous layer slurry, which can be sealed and stored in a refrigerator. Add a certain amount of mesoporous layer slurry on the TiO2 dense layer, and use a scraping rod to evenly scrape the mesoporous layer slurry to a thickness of about 10 microns. After naturally drying in a clean bench, sinter at 450°C in a muffle furnace for 30 minutes to obtain a TiO2 mesoporous layer.

[0045] 4) Preparation of the perovskite photoelectric active layer: Pour CsI and BiI3 in a molar ratio of 1:2 into a volumetric flask. Then, pipette 0.8 mL of DMF and 0.2 mL of DMSO into the flask to prepare a precursor solution with a BiI3 concentration of 0.67 M. Stir on a magnetic stirrer for 15 minutes to thoroughly mix. Add 0.044 mL of HI while stirring to promote dissolution of the chemicals and perovskite formation. Stir and react for 24 hours to obtain the photoelectric active layer solution, which is ready for use. Add a sufficient amount of the photoelectric active layer solution onto the TiO2 mesoporous layer to cover the entire surface.

[0046] 5) Preparation of Pt counter electrode: Take a certain amount of chloroplatinic acid (H 14 C 16 O6Pt) and a certain amount of isopropyl alcohol to prepare a 0.004M chloroplatinic acid solution. After sealing, ultrasonicate the solution in an ultrasonic cleaner for 15 minutes to disperse it. Store in a sealed refrigerator for reuse. In an environment with 20% humidity, apply the chloroplatinic acid solution dropwise to a clean, pre-cleaned FTO conductive substrate. After air drying, sinter the substrate in a muffle furnace at 400°C for 30 minutes. Repeat this process six times to produce a uniform, metallic, and agglomerated platinum film approximately 1 micron thick on the FTO substrate.

[0047] 6) The Pt counter electrode obtained in step 5) is hot-pressed at 95° C. on the perovskite photoelectric active layer prepared in step 4), and annealed on a hot plate at 95° C. for 5 minutes, and then heated to 105° C. and annealed for 5 minutes.

[0048] The Pt counter electrode and electron transport layer in the battery device prepared above were led out with wires and the photoelectric performance was tested. Figure 2 As shown. Figure 2 It can be seen that the cell efficiency measured under a standard simulated sunlight (AM1.5) at room temperature is 1.03%, and the short-circuit current, open-circuit voltage, and fill factor are 6.55 mA / cm 2 , 0.443V, 35.3%.

[0049] The statistical results of the open circuit voltage of the above battery devices under light and dark states are as follows: Figure 3 As shown. Figure 3 It can be seen that in the dark state, the prepared battery has an open circuit voltage of about 0.3V, which indicates that the battery has stored a certain amount of electrical energy at this time and can power external electrical devices.

[0050] The above thirty battery devices are connected in series after being charged by light, and the effect of driving LED lights in the dark state is as follows: Figure 4 As shown, the curve of LED lamp working time in dark state and battery illumination time is as follows Figure 5 As shown. Figure 4 It can be seen that in the dark state, the battery pack can drive the LED light to work. Figure 5 It can be seen that as the illumination time increases, the working time of the LED lamp increases linearly, which means that the longer the illumination time, the more electrical energy the battery can store.

[0051] The Pt counter electrode and electron transport layer in the battery device prepared above were led out with wires and the charge and discharge performance was tested. Figure 8 The charge and discharge cycle test results are shown in Figure 9 As shown. Figure 8 It can be seen that the assembled battery has a clear charging and discharging platform. Figure 9 It can be seen that the assembled battery has certain cycle charge and discharge performance.

[0052] Example 2-3:

[0053] A rechargeable and dischargeable battery and a photorechargeable battery based on bismuth material, wherein the battery structure includes an FTO conductive substrate, an electron transport layer composed of a TiO2 dense layer and a TiO2 mesoporous layer, a photoelectric active layer based on the Bi element, and a platinum counter electrode, recorded as FTO / TiO2 / Cs3Bi2I9 / Pt / FTO.

[0054] The preparation method of the above-mentioned FTO / TiO2 / Cs3Bi2I9 / Pt / FTO battery device comprises the following steps:

[0055] 1) Pretreatment and cleaning of the FTO conductive substrate: the preparation process is the same as in Example 1;

[0056] 2) Preparation of TiO2 dense layer: the preparation process is the same as that in Example 1;

[0057] 3) Preparation of TiO2 mesoporous layer: the preparation process is the same as that in Example 1;

[0058] 4) Preparation of the perovskite photoelectric active layer: The difference from Example 1 is the different molar ratio of CsI and BiI3. Specifically, CsI and BiI3 were taken at different molar ratios of 1:1 and 1:3 respectively and poured into a volumetric flask. Then, 0.8 mL of DMF and 0.2 mL of DMSO were pipetted into the volumetric flask in sequence to prepare a precursor solution with a BiI3 concentration of 0.67 M. The solution was then stirred on a magnetic stirrer for 15 minutes to thoroughly mix. 0.044 mL of HI was then injected while stirring to promote the dissolution of the drug and the formation of perovskite. The reaction was stirred for 24 hours to obtain a photoelectric active layer solution, which was ready for use. A certain amount of the photoelectric active layer solution was added dropwise onto the TiO2 mesoporous layer so that the solution covered the entire surface of the TiO2 mesoporous layer.

[0059] 5) Preparation of Pt counter electrode: The preparation process is the same as that in Example 1;

[0060] 6) The Pt counter electrode obtained in step 5) is hot-pressed at 95° C. on the perovskite photoelectric active layer prepared in step 4), and annealed on a hot plate at 95° C. for 5 minutes, and then heated to 105° C. and annealed for 5 minutes.

[0061] The Pt counter electrode and electron transport layer in the battery device prepared above were led out with wires and the photoelectric performance was tested. Figure 6 As shown in Table 1, the specific photoelectric parameters are shown in Table 1. Figure 6 Comparison found that compared with the molar ratios of 1:1 and 1:3, when the molar ratio of CsI and BiI3 is 1:2, the FTO / TiO2 / Cs3Bi2I9 / Pt / FTO battery device has higher short-circuit photocurrent and photoelectric conversion efficiency.

[0062] Table 1 Characteristic photoelectric data of FTO / TiO2 / Cs3Bi2I9 / Pt / FTO cell devices

[0063]

[0064] Example 4:

[0065] A rechargeable and dischargeable battery and a photorechargeable battery based on bismuth material, wherein the battery structure includes an FTO conductive substrate, an electron transport layer composed of a TiO2 dense layer and a TiO2 mesoporous layer, a photoelectric active layer based on Bi element, and a carbon counter electrode, recorded as FTO / TiO2 / Cs3Bi2I9 / C / FTO.

[0066] The preparation method of the above-mentioned FTO / TiO2 / Cs3Bi2I9 / C / FTO battery device has the following specific steps:

[0067] 1) Pretreatment and cleaning of the FTO conductive substrate: the preparation process is the same as in Example 1;

[0068] 2) Preparation of TiO2 dense layer: the preparation process is the same as that in Example 1;

[0069] 3) Preparation of TiO2 mesoporous layer: the preparation process is the same as that in Example 1;

[0070] 4) Preparation of perovskite photoelectric active layer: the preparation process is the same as that in Example 1;

[0071] 5) Preparation of carbon counter electrode. Take 0.2g PVDF powder and add it to a beaker containing 10ml isopropanol. After stirring for 10 minutes, add 0.2g titanium dioxide P25 powder, 0.5g carbon black powder and 2mL N-methylpyrrolidone in sequence. Seal the beaker and place it in an ultrasonic cleaner for 30 minutes. Then stir it on a magnetic stirrer for 24 hours to mix evenly to obtain carbon slurry. Seal it and store it for reuse. Take a clean FTO conductive substrate that has been pre-treated and cleaned, add a certain amount of carbon slurry, and use a scraping rod to scrape it. After it is naturally dried, dry it in a drying oven at 70°C for 15 minutes to produce a flat carbon electrode film on the FTO conductive substrate with a thickness of about 10 microns.

[0072] 6) The carbon counter electrode obtained in step 5) is hot-pressed at 95° C. on the perovskite photoelectric active layer prepared in step 4), and annealed on a hot plate at 95° C. for 5 minutes, and then heated to 105° C. and annealed for 5 minutes.

[0073] The carbon counter electrode and electron transport layer in the battery device prepared above were led out with wires and the photoelectric performance was tested. Figure 7 As shown. Figure 7 It can be seen that the cell efficiency measured under a standard simulated sunlight (AM1.5) at room temperature is 0.65%. The short-circuit current, open-circuit voltage, and fill factor are 4.02 mA / cm 2 , 0.467V, 34.67%.

[0074] In summary, it can be seen that the battery device of the present invention can be used as both a photorechargeable battery and a rechargeable and dischargeable battery with good charge and discharge performance. Photorechargeable batteries based on this type of material are expected to realize the practical application of light-self-rechargeable secondary batteries.

Claims

1. A method for preparing a rechargeable and dischargeable battery and a photorechargeable battery based on bismuth material, characterized in that: The rechargeable and dischargeable battery and the photorechargeable battery based on bismuth element material sequentially include an FTO conductive substrate, an electron transport layer, a photoelectric active layer based on Bi element, and a platinum or carbon counter electrode; The electron transport layer is composed of a porous oxide dense layer and a porous oxide mesoporous layer, and the porous oxide is TiO2, SnO2, ZnO or Sb2O5; The steps include: 1) Pretreatment of FTO conductive substrate; 2) Preparation of electron transport layer; 3) Preparation of a Bi-based photoelectric active layer: CsI and BiI3 are dissolved in a mixed solvent of DMF and DMSO in a certain proportion to prepare a precursor solution with a BiI3 concentration of 0.2-0.7 M. An appropriate amount of HI is then added and the mixture is stirred for 20-30 hours to obtain a photoelectric active layer solution. The photoelectric active layer solution is then dripped onto the electron transport layer to cover the entire surface of the electron transport layer. 4) Preparation of platinum or carbon counter electrode; 5) hot pressing the platinum or carbon counter electrode obtained in step 4) on the photoelectric active layer obtained in step 3) at 80-110° C., then annealing on a hot plate at 85-95° C. for 3-10 minutes, and then heating to 100-110° C. and annealing for 3-10 minutes to obtain the product; In step 3), the molar ratio of CsI to BiI3 is 1:1-3, and the amount of HI added is 4-6% of the volume of the mixed solvent.

2. The method for preparing a rechargeable and dischargeable battery and a photorechargeable battery based on bismuth material according to claim 1, wherein: The volume ratio of DMF to DMSO is 4:1-2.

3. The method for preparing a rechargeable and dischargeable battery and a photorechargeable battery based on bismuth material according to claim 1, wherein: The pretreatment of the FTO conductive substrate in step 1) is specifically as follows: the FTO conductive substrate is first ultrasonically cleaned with detergent, anhydrous ethanol, isopropyl alcohol, and deionized water in sequence, dried, and then placed in a plasma cleaning machine for cleaning at room temperature.

4. The method for preparing a rechargeable and dischargeable battery and a photorechargeable battery based on bismuth material according to claim 1, wherein: The preparation of the electron transport layer in step 2) consists of the preparation of a TiO2 dense layer and the preparation of a TiO2 mesoporous layer; The TiO2 dense layer is prepared by dissolving 5 mL of isopropyl titanate in 15-20 mL of n-butanol to obtain a dense layer precursor solution, then coating the dense layer precursor solution on a pretreated clean FTO conductive substrate, and then sintering it in a muffle furnace at 450-500° C. for 0.5-1.5 h. The preparation of the TiO2 mesoporous layer is specifically as follows: 1g of titanium dioxide P25 powder is evenly mixed with 10-20mL of n-butanol and 0.1-0.2ml of Triton X-100 to obtain a mesoporous layer slurry; the mesoporous layer slurry is then dropped onto the TiO2 dense layer, and the mesoporous layer slurry is evenly scraped with a scraping rod. After naturally drying in a clean bench, the slurry is sintered in a muffle furnace at 450-500°C for 0.5-1.5h to obtain the obtained layer.

5. The method for preparing a rechargeable and dischargeable battery and a photorechargeable battery based on bismuth material according to claim 1, wherein: The platinum counter electrode in step 4) is prepared by dissolving chloroplatinic acid in isopropyl alcohol to prepare a chloroplatinic acid solution with a concentration of 0.004-0.010M. The chloroplatinic acid solution is then drop-coated on a pretreated clean FTO conductive substrate in an environment with an air humidity of 15-25%. After natural drying, the solution is sintered in a muffle furnace at 360-420°C for 15-40 minutes. The above operation is repeated several times to form a platinum metal film with metallic luster, uniformity and no agglomeration on the FTO conductive substrate.

6. The method for preparing a rechargeable and dischargeable battery and a photorechargeable battery based on bismuth material according to claim 1, wherein: The carbon counter electrode described in step 4) is prepared as follows: 0.2g of PVDF powder is mixed with 10-20ml of isopropanol, 0.2-0.3g of titanium dioxide P25 powder, 0.4-0.6g of carbon black powder, and 2-6mL of N-methylpyrrolidone to obtain a carbon slurry; the carbon slurry is then dropped onto a pretreated clean FTO conductive substrate and coated with a doctor blade. After natural drying, the slurry is dried in a drying oven at 60-80°C for 15-30 minutes to produce a flat carbon electrode film on the FTO conductive substrate.

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