Live algae-based light synergism water photovoltaic generator

Abstract

The invention discloses a live-algae-based light synergism hydroelectric generator, which comprises a top electrode, a live-algae biological membrane and a bottom electrode, and is characterized in that the upper surface of the live-algae biological membrane is connected with the top electrode in an attached manner, and the lower surface of the live-algae biological membrane is connected with the bottom electrode in an attached manner. According to the light-synergism water photovoltaic power generator based on the living algae, a complex self-assembly process is not needed, moisture and solar energy in the environment are spontaneously captured by means of rich chlorophyll and water absorption cells in the living algae biological membrane, continuous and autonomous power generation is achieved, the adopted living algae biological membrane is good in overall surface appearance, and the service life of the living algae biological membrane is prolonged. Chap does not easily occur under the condition of dry air, the storage is easy, and the healing effect is good; under the condition that the humidity is 90%, the living algae biofilm with the area of 1.75 cm < 2 > generates a short-circuit current of about 0.57 microamperes and an open-circuit voltage of 0.52 V, and the short-circuit current and the open-circuit voltage are kept stable, so that the device has good power generation performance and stability, has a wide application prospect in the field of energy supply, and promotes the development of a sustainable energy technology.

Description

Technical Field

[0001] The present invention relates to the technical field of biomass energy, and more specifically, to a photo-enhanced hydrovoltaic generator based on living algae. Background Art

[0002] With the current energy shortage and increasingly severe environmental pollution, it is urgent to explore green renewable energy. Hygroelectricity generator (HEG) can directly use environmental moisture to generate electricity. It has attracted extensive attention from researchers and is one of the fastest-growing and most promising power generation technologies in hydrovoltaic technology. After years of improvement, the power density of HEG has increased from the initial pW / cm 2 The level has been upgraded to the current μW / cm 2 However, the single energy source limits the output efficiency of HEG. Studies have shown that multi-energy coupling power generation is one of the most direct and effective ways to improve the output performance of generators. Therefore, designing HEGs that can capture multiple energy sources is crucial to improving output power.

[0003] The phenomenon of synergistic absorption of multiple energy sources in the environment is widely present in nature. For example, plants can capture water and solar energy at the same time through photosynthesis. Inspired by this, hydrovoltaic-photovoltaic electricity generators (HPEGs) are expected to achieve synergistic conversion of multiple energies, thereby significantly improving the power generation efficiency. Many scholars have added photosensitive materials to the original hygroscopic materials of HEG to construct composite functional materials to achieve the purpose of absorbing water and solar energy at the same time. For example, some studies have combined polystyrene sulfonic acid (PSSA) with rose pigment (R) to prepare PSSA-RHPEG, which has the ability to couple the absorption of water and solar energy, significantly improving the output performance of the generator. Other researchers have used Geobacter sulfurreducens (Gs) biofilm and different photosensitive materials to self-assemble biohybrid HPEG, achieving new performance breakthroughs. However, the above-mentioned HPEGs all rely on complex self-assembly processes, which increases the cost and limits the practical application of the generator. Therefore, it is necessary to develop a hydrovoltaic generator with broad application prospects that can spontaneously capture water and solar energy in the environment. Summary of the invention

[0004] In order to overcome the problems of generator output efficiency and power generation materials in the prior art, one of the objects of the present invention is to provide a photo-enhanced hydrovoltaic generator based on living algae, a second object of the present invention is to provide a method for preparing the photo-enhanced hydrovoltaic generator based on living algae, and a third object of the present invention is to provide applications of the photo-enhanced hydrovoltaic generator based on living algae.

[0005] The first aspect of the present invention provides a photo-enhanced hydroelectric generator based on living algae, comprising a top electrode, a living algae biofilm and a bottom electrode, wherein the upper surface of the living algae biofilm is fitted and connected to the top electrode, and the lower surface of the living algae biofilm is fitted and connected to the bottom electrode.

[0006] In some embodiments of the present invention, the microorganisms in the living algal biofilm are cyanobacteria.

[0007] In some embodiments of the invention, the area of ​​the living algae biofilm is 1.75 cm 2 , the thickness of the living algae biofilm is 14 μm.

[0008] In some embodiments of the present invention, the top electrode is an electrode having a mesh structure.

[0009] In some embodiments of the present invention, the mesh size of the top electrode is 100-200 mesh.

[0010] In some embodiments of the present invention, the top electrode is a stainless steel electrode, and the area of ​​the top electrode is 2 cm 2 .

[0011] In some embodiments of the present invention, the bottom electrode is ITO conductive glass, and the internal resistance of the bottom electrode is less than 10Ω / cm 2 , the area of ​​the bottom electrode is 2cm 2 .

[0012] The second aspect of the present invention provides a method for preparing a photo-enhanced hydroelectric generator based on living algae, comprising the following steps:

[0013] A cyanobacteria liquid is coated on the upper surface of the bottom electrode and placed in a culture liquid to allow the cyanobacteria to grow in situ. After the cyanobacteria grow to maturity, the bottom electrode with the cyanobacteria grown is taken out and dried overnight to form a live algae biofilm on the bottom electrode. A top electrode is covered on the live algae biofilm, and the top electrode is bonded to the upper surface of the live algae biofilm to obtain a photo-efficient hydrovoltaic generator based on live algae.

[0014] In some embodiments of the present invention, cyanobacteria are grown in situ on ITO glass. After the cyanobacteria reach a mature state, they are dried overnight at 20-40° C. to form a living algae biofilm on the ITO glass.

[0015] The third aspect of the present invention provides an application of a photo-enhanced hydrovoltaic generator based on living algae in power generation.

[0016] The beneficial effects of the present invention are as follows: (1) The surface of the living algae biofilm used in the present invention has a good overall morphology, is not prone to cracking in dry air, is easy to store, and has a good healing effect; under high humidity of 90%, the output performance of the hydrovoltaic generator of the present invention is excellent; the area is 1.75cm 2 The living algae biofilm generates a short-circuit current of about 0.57 μA and an open-circuit voltage of 0.52 V and remains stable, and has the ability to charge capacitors and power small calculators. The living algae-based photoelectric generator of the present invention has good power generation performance and stability, provides a good foundation for powering various electronic devices in practical applications, and is suitable for a variety of application scenarios;

[0017] (2) The cyanobacteria used in the present invention contain a large number of oxygen-containing groups and photogenerated electrons. When the living algae biofilm is placed in a humid environment, the oxygen-containing groups adsorb water molecules and release charged ions. After connecting to an external circuit, the charged ions gather at one end of the biofilm, resulting in a concentration gradient in the direction perpendicular to the bottom electrode of the biofilm. Under the operation of the concentration gradient, the transfer of charges generates a hydroelectric field (E H ). P680 in Photosystem II (PSII) absorbs light energy and is excited to become P680*, which releases electrons by oxidizing water. The released electrons are transferred to PSI through a series of electron carriers for electron supplementation. P700 in Photosystem I (PSI) absorbs light energy and is excited to become P700*, releasing electrons, which are eventually transferred to ferredoxin (Fd) and NADP + , and eventually NADPH is formed. The directional movement of photogenerated electrons leads to the generation of photovoltaic current, which in turn generates a photovoltaic electric field (Ep), E H The two electric fields of Ep and Ep are superimposed to form the total electric field (E total =E H +Ep). The above is the principle of the generator of the present invention using moisture power generation and light gain. Then the superposition of the electric fields of moisture power generation and light gain makes the electrical output performance of the present invention under moisture-light coupling conditions better than the electrical output performance under moisture or light alone.

[0018] (3) The photoelectric generator based on living algae of the present invention does not need to go through a complicated self-assembly process. It can spontaneously capture moisture and solar energy in the environment by relying on the abundant chlorophyll and water-absorbing cells inside the living algae biofilm, thus achieving continuous autonomous power generation. It can be used as a generator with broad application prospects in the field of energy supply and promote the development of sustainable energy technology. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is a structural schematic diagram and a physical picture of a photo-enhanced hydroelectric generator based on living algae according to Example 1 of the present invention, wherein A is a structural schematic diagram and B is a physical picture.

[0020] Figure 2 A is a cross-sectional view of a living algae biofilm of a photo-enhanced hydroelectric generator based on living algae according to Example 1 of the present invention, and B is a partial enlarged cross-sectional view of the living algae biofilm and a cyanobacteria live or dead staining view.

[0021] Figure 3 This is a schematic diagram of the working mechanism of a photo-enhanced hydroelectric generator based on living algae according to Example 1 of the present invention.

[0022] Figure 4 This is a diagram of the open circuit voltage of a photo-enhanced hydroelectric generator based on living algae under different relative humidities in Example 3 of the present invention.

[0023] Figure 5 This is a graph showing the charge and discharge results of a photo-enhanced hydroelectric generator based on living algae under a load of 500KΩ in Example 3 of the present invention.

[0024] Figure 6 This is a response diagram of a photo-enhanced hydroelectric generator based on living algae to periodic illumination at 90% RH in Example 3 of the present invention.

[0025] Figure 7 This is a continuous voltage and current test diagram of a photo-enhanced hydroelectric generator based on living algae in Example 3 of the present invention under different light intensities and 90% RH.

[0026] Figure 8 The voltage changes of the generators prepared from cyanobacterial cells with different activities in Example 3 of the present invention in response to light are relatively small.

[0027] Fig. 9 This is a comparison chart of the output performance of the photo-enhanced hydrovoltaic generators prepared using dead algae and living algae respectively in Example 3 of the present invention.

[0028] Fig.10 This is a schematic diagram of charging a capacitor using a photo-enhanced hydroelectric generator based on living algae in Example 3 of the present invention.

[0029] Fig.11 This is a schematic diagram of a photo-enhanced hydroelectric generator based on living algae in Example 3 of the present invention supplying power to a small calculator.

[0030] Fig.12 This is a performance comparison diagram of a photo-enhanced hydrovoltaic generator based on living algae and other electroactive bacteria generators in Example 3 of the present invention, wherein A is an output voltage diagram of the Gs hydrovoltaic generator, the NWs hydrovoltaic generator and the Gs-withoutNWs hydrovoltaic generator, and B is an output voltage diagram of a photo-enhanced hydrovoltaic generator based on living algae. DETAILED DESCRIPTION

[0031] The present invention is further described in detail through specific implementation cases, and it should be understood that these embodiments are only used to illustrate the present invention and are not used to limit the scope of protection of the present invention. After reading the present invention, the modifications of various equivalent forms of the present invention by those skilled in the art are all limited by the claims attached to this application. Unless otherwise specified, all raw materials and reagents of the present invention are raw materials and reagents that can be purchased in the conventional market.

[0032] The blue algae used in the present invention is derived from the Freshwater Algae Culture Collection at the Institute of Hydrobiology (FACHB) of the Chinese Academy of Sciences.

[0033] Example 1

[0034] A photo-enhanced hydroelectric generator based on living algae adopts a sandwich structure, which comprises, from top to bottom, a top electrode 1, a living algae biofilm 2, and a bottom electrode 3. The upper surface of the living algae biofilm 2 is bonded to the top electrode 1, and the lower surface of the living algae biofilm 2 is bonded to the bottom electrode 3. In the present invention, a 100-200 mesh porous stainless steel mesh is used as the top electrode 1, an ITO conductive glass is used as the bottom electrode 3, and the living algae biofilm 2 is a cyanobacteria biofilm. The structural schematic diagram of the photo-enhanced hydroelectric generator based on living algae is shown in FIG. Figure 1 As shown in A, the actual picture is as follows Figure 1 As shown in B. The living algae biofilm of the power generation device of this embodiment was tested for some characterizations, such as Figure 2 As shown in Figure A, the thickness of the living algae biofilm is 14 μm; Figure 2 As shown in B, in the test environment, the cyanobacteria in the living algae biofilm remain highly active, with an activity as high as 90%, proving that the cyanobacteria in the biofilm used in this example are living algae.

[0035] Example 2

[0036] A method for preparing a photo-enhanced hydrovoltaic generator based on living algae comprises the following steps:

[0037] Apply the cyanobacteria solution to an area of ​​2 cm 2 The cyanobacteria were placed on the ITO glass bottom electrode in the culture medium until they grew to maturity, and then dried at room temperature at 25°C to obtain a living algae biofilm with an area of ​​1.75 cm 2 , with a thickness of 14 μm, and then a porous stainless steel mesh was placed on the living algae biofilm as the top electrode. The top electrode was 100 mesh and its area was 2 cm 2 , thus obtaining a photo-enhanced hydrovoltaic generator based on living algae.

[0038] Example 3: Verification of the power generation effect of a photo-enhanced hydroelectric generator based on living algae

[0039] 3.1 A generator system based on living algae photocatalytic hydroelectric generator

[0040] The top electrode and bottom electrode of the photo-enhanced hydroelectric generator based on living algae in Example 1 were connected to an electrochemical workstation to form a closed loop, and placed in an environment with a relative humidity of 90% to monitor the electrical signals generated in real time. Figure 3 .

[0041] like Figure 3 As shown, when the relative humidity is 90%, after the living algae biofilm absorbs moisture from the air, the hydrophilic functional groups on the surface of the biofilm absorb water molecules and release charged ions in situ. The charged ions move in a directional manner due to the concentration gradient at both ends of the biofilm. The directional movement of the charged ions causes a potential difference to form at both ends of the biofilm to generate a hydrovoltaic field. The photosynthetic pigments (such as chlorophyll a, phycocyanin and phycoerythrin) in the cyanobacterial cells in the biofilm absorb light energy and are excited to generate photogenerated electrons. The directional transfer of the photogenerated electrons generates a photovoltaic electric field. The two are superimposed, so that a photo-enhanced hydrovoltaic generator based on living algae in Example 1 generates a stable open circuit voltage.

[0042] 3.2 Effects of different humidity on the power generation performance of a photo-enhanced hydrovoltaic generator based on living algae

[0043] According to the method in 3.1, three groups of photo-enhanced hydroelectric generators based on living algae of Example 1 were assembled to form closed loops, and then placed in environments with relative humidity of 10%, 50%, and 90%, respectively, to monitor the electrical signals generated by the three groups of generators in real time.

[0044] like Figure 4 As shown in the figure, at a relative humidity of 90%, a photo-enhanced hydrovoltaic generator based on living algae has the highest open circuit voltage and short circuit current, which are 0.52V and 0.57μA respectively. As the relative humidity in the environment gradually decreases, the open circuit voltage and short circuit current of the generator both decrease, so the output performance of the generator is directly affected by the relative humidity of the environment.

[0045] 3.3 Charging and discharging test of a photo-enhanced hydrovoltaic generator based on living algae

[0046] The photoelectric generator based on living algae in Example 1 was placed in an environment with a relative humidity of 90% and loaded with 500KΩ to detect the voltage and current of its charge and discharge. The results are shown in Figure 5 .

[0047] Depend on Figure 5It can be seen that this embodiment carried out a charge and discharge experiment on the generator, and its performance remained relatively stable after multiple charge and discharge cycles, which proves that the generator has excellent self-charging ability.

[0048] 3.4 Effects of periodic illumination on a photo-enhanced hydrovoltaic generator based on living algae

[0049] A photo-enhanced hydrovoltaic generator based on living algae in Example 1 was subjected to periodic illumination (100 s of illumination, 100 s of darkness, alternating for 5 cycles) in a 90% humidity environment, and the voltage signal output by the generator was measured. Figure 6 .

[0050] like Figure 6 As shown, the power generation performance of a photo-enhanced hydrovoltaic generator based on living algae is affected by periodic illumination. When illuminated, its output voltage gradually increases with the increase of illumination time. When dark, its output voltage gradually decreases with the increase of darkness time, which proves the existence of photovoltaic effect in this photo-enhanced hydrovoltaic generator based on living algae.

[0051] 3.5 Effects of different light intensities on a photo-enhanced hydrovoltaic generator based on living algae

[0052] The algae-based photoelectric generator of Example 1 was placed in an environment with a relative humidity of 90% and a 0.5 mW / cm 2 Light of 1.0 mW / cm was applied for 1 to 2 hours. 2 Light was applied at 1.5 mW / cm for 2 to 3 hours. 2 The output voltage and current of the generator were measured within 0 to 3 hours under the illumination of Figure 7 .

[0053] like Figure 7 As shown, as the light intensity gradually increases, the output voltage and output current gradually increase. This shows that a photo-enhanced hydrovoltaic generator based on living algae has a gain response to light, and the power generation performance of the generator increases with the increase of light intensity.

[0054] 3.6 Voltage changes of photo-enhanced hydrovoltaic generators in response to light in different active biofilms

[0055] The living algae biofilm in the photo-enhanced hydrovoltaic generator based on living algae in Example 1 was replaced with a dead algae biofilm as a control group, and the photo-enhanced hydrovoltaic generator based on living algae in Example 1 was used as a treatment group, and was placed in an environment with a relative humidity of 90%, without applying light within 0-1h, and applying light with an intensity of 1.5mW / cm for 1-2h. 2 The output voltage of the generator was measured within 0 to 2 hours under the illumination of Figure 8 .

[0056] Figure 8 As shown, in an environment with a relative humidity of 90%, the output voltage of the generator equipped with a live bacterial biofilm is higher than that of the generator equipped with a dead bacterial biofilm, regardless of whether light is applied. 2 After irradiation with light, the output voltage of the generator equipped with live bacterial biofilm increased significantly more than that of the generator equipped with dead bacterial biofilm, and its voltage change in response to light was significantly higher than that of the generator equipped with dead bacterial biofilm. This shows that the biofilm prepared with live algae has a better effect in generating electricity.

[0057] The treatment group and the control group of this embodiment were placed in an environment with a relative humidity of 90% without applying light. The output voltage and current of the two groups of generators were measured within 1 hour. The results are shown in Fig. 9 .

[0058] like Fig. 9 As shown, the power output performance of the biofilm generator using living algae is significantly improved, proving that the activity of cyanobacteria cells seriously affects the power output performance of the photo-enhanced hydrovoltaic generator.

[0059] 3.7 Charging and power supply application of a photo-enhanced hydrovoltaic generator based on living algae

[0060] A plurality of the photo-enhanced hydroelectric generators based on living algae in Example 1 are connected in series and in parallel to charge the capacitors. Fig.10 , the charged capacitor can directly power a small calculator, such as Fig.11 As shown. Fig.10 , Fig.11 It can be seen that the photo-enhanced hydroelectric generator based on living algae of the present invention can be used for direct applications of charging and power supply.

[0061] 3.8 Comparison of power generation performance between a photo-enhanced hydrovoltaic generator based on living algae and other biofilm generators

[0062] A photo-enhanced hydrovoltaic generator based on living algae in Example 1 was used as the treatment group, and the living algae biofilm was replaced by a Geobacter sulfurreducens microbial film (Gs bacteria microbial film), a protein nanowire microbial film (NWs microbial film), and a Geobacter sulfurreducens microbial film without the protein nanowires (Gs-withoutNWs microbial film) to prepare a Gs hydrovoltaic generator, a NWs hydrovoltaic generator, and a Gs-withoutNWs hydrovoltaic generator, which were respectively used as control 1, control 2, and control 3.

[0063] The preparation method of Gs bacterial biofilm is as follows: S1. After culturing Geobacter sulfurreducens (abbreviated as Gs), centrifuge and resuspend with ultrapure water to obtain a concentrated bacterial solution of Geobacter sulfurreducens, wherein the concentration of the concentrated bacterial solution of Geobacter sulfurreducens is 1g of wet bacteria per 10mL of bacterial solution; S2. The concentrated bacterial solution of Geobacter sulfurreducens is coated on the upper surface of the bottom electrode, and after drying, a Gs bacterial microbial film is formed on the bottom electrode.

[0064] The preparation method of NWs microbial film is as follows: S1. Protein nanowires (Nanowires, abbreviated as NWs) are chemically treated with sulfur-reducing Bacillus, and the supernatant containing NWs is obtained after centrifugation, and the concentrated bacterial solution of protein nanowires is resuspended, and the concentration of the concentrated bacterial solution of protein nanowires is 1g of wet bacteria per 10mL of bacterial solution; S2. The concentrated bacterial solution of protein nanowires is coated on the upper surface of the bottom electrode, and after drying, a NWs microbial film is formed on the bottom electrode.

[0065] The preparation method of Gs-withoutNWs microbial film is as follows: S1. Remove the sulfur-reducing Geobacter (Gs-withoutNWs) from the protein nanowires, chemically treat the sulfur-reducing Geobacter, obtain the precipitate containing Gs-withoutNWs after centrifugation, resuspend it to obtain the concentrated bacterial solution of Gs-withoutNWs, the concentration of the concentrated bacterial solution of Gs-withoutNWs is 1g of wet bacteria per 10mL of bacterial solution; S2. Coat the concentrated bacterial solution of Gs-withoutNWs on the upper surface of the bottom electrode, and after drying, form a Gs-withoutNWs microbial film on the bottom electrode.

[0066] The treatment group, control 1, control 2 and control 3 were placed in an environment with a relative humidity of 90% without applying light, and the output voltage was measured within 5 hours. Fig.12 .

[0067] Depend on Fig.12 It can be seen that the output voltage of the photo-enhanced hydroelectric generator based on living algae of the present invention is higher than the output voltages of the other three hydroelectric generators. This proves that the living algae biofilm of the present invention exhibits better electrical output performance than other electroactive bacteria while maintaining the activity of cyanobacteria cells.

[0068] The above are only some embodiments of the present invention. For those skilled in the art, several modifications and improvements may be made without departing from the inventive concept of the present invention, which all fall within the protection scope of the present invention.

Claims

1. A photo-enhanced hydroelectric generator based on living algae, characterized in that: It comprises a top electrode, a live algae biofilm and a bottom electrode. The upper surface of the live algae biofilm is fitted and connected to the top electrode, and the lower surface of the live algae biofilm is fitted and connected to the bottom electrode.

2. The photo-enhanced hydroelectric generator based on living algae according to claim 1, characterized in that: The microorganisms in the living algae biofilm are cyanobacteria.

3. The photo-enhanced hydroelectric generator based on living algae according to claim 1, characterized in that: The area of ​​the living algae biofilm is 1.75 cm 2 , the thickness of the living algae biofilm is 14 μm.

4. The photo-enhanced hydroelectric generator based on living algae according to claim 1, characterized in that: The top electrode is an electrode with a mesh structure.

5. The photo-enhanced hydroelectric generator based on living algae as claimed in claim 4, characterized in that: The mesh number of the top electrode is 100-200 meshes.

6. The photo-enhanced hydroelectric generator based on living algae as claimed in claim 5, characterized in that: The top electrode is a stainless steel electrode, and the area of ​​the top electrode is 2 cm 2 .

7. The photo-enhanced hydroelectric generator based on living algae according to claim 1, characterized in that: The bottom electrode is ITO conductive glass, and the internal resistance of the bottom electrode is less than 10Ω / cm 2 , the area of ​​the bottom electrode is 2cm 2 .

8. The method for preparing a photo-enhanced hydroelectric generator based on living algae according to claim 1, characterized in that: The following steps are involved: A cyanobacteria liquid is coated on the upper surface of the bottom electrode and placed in a culture solution to allow the cyanobacteria to grow in situ. After the cyanobacteria grow to maturity, the bottom electrode with the cyanobacteria grown is taken out and dried overnight to form a live algae biofilm on the bottom electrode. A top electrode is covered on the live algae biofilm, and the top electrode is bonded to the upper surface of the live algae biofilm to obtain a photoelectric hydrovoltaic generator based on live algae.

9. The method for preparing a photo-enhanced hydroelectric generator based on living algae according to claim 8, characterized in that: Cyanobacteria are grown in situ on ITO glass. After the cyanobacteria reach a mature state, they are dried overnight at 20-40° C. to form a live algae biofilm on the ITO glass.

10. Use of the photo-enhanced hydroelectric generator based on living algae as described in claims 1-7 in power generation.

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