Artificial photosynthesis system and preparation method thereof

Abstract

The embodiment of the invention relates to an artificial photosynthesis system and a preparation method thereof. The artificial photosynthesis system comprises a semiconductor film which is configured to be capable of carrying out photoelectric conversion to generate photo-induced electrons and has biocompatibility; and a first microorganism group which grows in a culture medium in contact with the semiconductor film and is capable of performing material conversion by using the photo-induced electrons generated by the photoelectric conversion. A semiconductor film material with stable light absorption is adopted, the stability is good, the system is simple and easy to recycle, the splitting efficiency of photo-generated excitons is improved, the recombination probability of current carriers is reduced, and when the material is combined with organisms such as bacteria with a catalytic function, the photocatalytic activity is improved. A'wireless' semiconductor film-microbial hybridization artificial photosynthesis system without external connection is designed and prepared, and reactions such as carbon dioxide reduction, nitrogen fixation and water decomposition can be carried out.

Description

Technical Field

[0001] The present application relates to the field of photocatalysis technology, and more specifically to an artificial photosynthesis system and a preparation method thereof. Background Art

[0002] In nature, plant photosynthesis utilizes sunlight energy to convert carbon dioxide into products essential to humans, such as carbohydrates and pharmaceuticals. However, natural photosynthesis suffers from a narrow absorption range, low light energy capture and photoelectric conversion efficiency, and a complex system. Inspired by natural photosynthesis, artificial photosynthesis systems have been designed that utilize photosensitive semiconductor materials to efficiently capture solar energy and drive the efficient separation and transfer of photogenerated electrons and holes, thereby catalyzing water decomposition or carbon dioxide reduction reactions. Artificial photosynthesis systems have high light capture capabilities and photoelectric conversion efficiencies, but their large-scale application is limited by factors such as the uncontrollable product selectivity, the high cost of photosensitive materials and catalysts, the material stability, and the susceptibility to heavy metal pollution.

[0003] Artificial photosynthesis systems based on the hybridization of microorganisms and photosensitizers are used to mimic the natural photosynthesis process. Using carbon dioxide and water as raw materials, they can drive the production of chemicals and fuels under sunlight while reducing greenhouse gas levels. They have garnered widespread attention in recent years. Biohybrid artificial photosynthesis systems combine the exceptional light-absorbing capacity of photosensitizers with the efficient catalytic functions of biological cells or enzymes, offering the dual capabilities of capturing and utilizing solar energy. However, the photosensitizers currently used in biohybrid artificial photosynthesis systems are mostly nanomaterials containing heavy metal elements or expensive electrode materials. Furthermore, hybrid systems can be complex systems requiring external wiring connections and assembly. While highly efficient in photoelectric conversion, numerous challenges remain regarding the direction of electron migration, catalyst costs, material recycling, and environmental protection. Consequently, the development of bio-based artificial photosynthesis systems has been slow.

[0004] On the other hand, semiconductor thin films have been widely used in artificial photosynthesis through photoelectrochemical catalysis, such as hydrogen production from water electrolysis, carbon dioxide reduction, and organic matter decomposition, due to their advantages: excellent light-harvesting performance, high photoelectric conversion efficiency, simple processing, good stability, large-scale fabrication, flexible thin films, low weight, and easy recycling. Therefore, the development of artificial photosynthesis systems based on semiconductor thin films is of great significance. Summary of the Invention

[0005] In response to the above technical problems, the present application provides an artificial photosynthesis system based on semiconductor thin films and microorganisms, which uses light-absorbing and stable semiconductor thin film materials, has good stability, a simple system and easy recycling, improves the splitting efficiency of photogenerated excitons, reduces the recombination probability of carriers, and is combined with organisms such as bacteria with catalytic functions to design and prepare a "wireless" semiconductor thin film-microorganism hybrid artificial photosynthesis system that does not require external connections, and can carry out reactions such as carbon dioxide reduction, nitrogen fixation, and water decomposition.

[0006] The first embodiment of the present application provides an artificial photosynthesis system, comprising: a semiconductor film configured to be capable of performing photoelectric conversion to generate photogenerated electrons and having biocompatibility; and a first microbial group that grows in a culture medium in contact with the semiconductor film and is capable of utilizing the photogenerated electrons generated by the photoelectric conversion to perform material conversion.

[0007] The second embodiment of the present application provides a method for preparing the artificial photosynthesis system of the first embodiment, comprising the following steps: preparing the semiconductor thin film; pre-culturing the first microbial group in a growth medium within a first time period; and adding the semiconductor thin film to the growth medium and co-culturing within a second time period to obtain the artificial photosynthesis system based on the semiconductor thin film and the first microbial group.

[0008] Compared with existing artificial photosynthesis systems, this application has the following advantages:

[0009] 1. This application hybridizes semiconductor thin films with microorganisms to construct a "semiconductor thin film-microorganism" artificial photosynthesis carbon fixation system. This achieves efficient energy and charge transfer from the semiconductor thin film to the microorganisms, ensuring the high conversion efficiency of the artificial photosynthesis system from the front end.

[0010] 2. The artificial photosynthesis system described in this application uses wireless semiconductor films and microorganisms to construct an artificial photosynthesis system, which can effectively reduce the complexity and cost of the device and is easy to recycle;

[0011] 3. The artificial photosynthesis system described in this application can convert carbon dioxide into medicine and food. The steps are simple and the process is clear, which can further improve the economic benefits of the system. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following will briefly introduce the drawings required for the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments described in this application. When appropriate, the same reference numerals are used in all drawings to refer to the same or similar parts. Such embodiments are illustrative and are not intended to be exhaustive or exclusive embodiments of the present device or method. In the drawings:

[0013] Figure 1 Schematic diagram of the structure of an artificial photosynthesis system according to an embodiment of the present application;

[0014] Figure 2(a)-Figure 2(h) is a schematic diagram of a layer structure of a semiconductor thin film according to an embodiment of the present application;

[0015] Figure 3 Schematic diagram of the structure of an artificial photosynthesis system according to another embodiment of the present application;

[0016] Figure 4 and Figure 5 is a schematic diagram of the principle of an artificial photosynthesis system according to another embodiment of the present application;

[0017] Figure 6 is a schematic flow chart of a method for preparing an artificial photosynthesis system according to an embodiment of the present application;

[0018] Figure 7(a)-Figure 7(f) is a graph showing the performance of the artificial photosynthesis system according to the present application, which shows the OD of S. ovata bacteria 600 , survival rate, acetic acid production and quantum efficiency values. DETAILED DESCRIPTION

[0019] In order to make the purpose, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions of the embodiments of the present application will be clearly and completely described below in conjunction with the drawings of the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the described embodiments of the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0020] Unless otherwise defined, the technical or scientific terms used in this application should have the usual meanings understood by people with ordinary skills in the field to which this application belongs. The "first", "second" and similar words used in this application do not indicate any order, quantity or importance, but are only used to distinguish different components. "Include" or "comprise" and similar words mean that the elements or objects appearing before the word include the elements or objects listed after the word and their equivalents, without excluding other elements or objects. "Connect" or "connected" and similar words are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "Up", "down", "left", "right" and the like are only used to indicate relative position relationships. When the absolute position of the object being described changes, the relative position relationship may also change accordingly.

[0021] In order to keep the following description of the embodiments of the present application clear and concise, detailed descriptions of known functions and known components are omitted in this application.

[0022] Figure 1 FIG. 1 shows a schematic structural diagram of the artificial photosynthesis system 100 of the present application. Figure 1 As shown, the artificial photosynthesis system 100 includes:

[0023] a semiconductor thin film 200 configured to be capable of performing photoelectric conversion to generate photogenerated electrons and having biocompatibility; and

[0024] The first microbial group 300 grows in a culture medium in contact with the semiconductor thin film 200 and can utilize the photogenerated electrons generated by the photoelectric conversion to perform material conversion.

[0025] In the artificial photosynthesis system 100 provided herein, to enable artificial photosynthesis, the semiconductor film 200 must be able to stably absorb light energy, capture photogenerated electrons from the light energy, and transfer these electrons to the first microbial population 300, enabling them to utilize these electrons for material conversion. Compared to existing artificial photosynthesis systems, this system achieves efficient energy and charge transfer and, because it eliminates the need for complex external wiring connections and assembly, significantly reduces the complexity and cost of the device.

[0026] like Figure 4 and Figure 5 As shown, the semiconductor film 200 and the first microbial group 300 can be located in a culture medium 400 (e.g. Figure 4 and Figure 5 The artificial photosynthesis system 100 is formed by placing the artificial photosynthesis system 100 in a liquid culture medium contained in a culture container 410 as shown in FIG.

[0027] In the embodiment of the present application, depending on the material of the substrate described below, the first microbial group 300 should be able to directly contact at least one surface of the semiconductor film 200 to achieve the transfer of photogenerated electrons. Specifically, the first microbial group 300 can grow as a biofilm (such as a biofilm) on at least one surface of the semiconductor film 200 (hard glass substrate). Figure 3-4 As shown), the microorganisms may not grow on the semiconductor film 200 (such as a flexible substrate, where the microorganisms are in direct contact with the semiconductor film 200 but do not grow on it).

[0028] In one embodiment, the semiconductor film 200 provided in the present application includes only a single active light-absorbing layer 240 (described below) required for photoelectric conversion, that is, a single independent active light-absorbing layer 240 without a substrate can perform photoelectric conversion to generate photogenerated electrons required for microorganisms to perform material conversion.

[0029] In another embodiment, to ensure more efficient electron transport, the semiconductor film 200 provided herein is a multilayer structure having multiple stacked layers. Optionally, in addition to the active light-absorbing layer 240 required for photoelectric conversion, the semiconductor film 200 may further include at least one of the following layers: a substrate 210, a bottom electrode 220, a first transport layer 230, a second transport layer 250, and a top electrode 260. These layers are stacked sequentially from bottom to top to form the layer structure of the semiconductor film 200.

[0030] The substrate 210 here can be a hard material such as glass or quartz glass, or a flexible substrate such as PEN, PET or PI.

[0031] The bottom electrode 220 and the top electrode 260 may be transparent electrodes, such as sputtered ITO or thin-layer Au or Ni electrodes.

[0032] The first transport layer 230 can be an electron transport layer for transporting photogenerated electrons (including ZnO, TiO2, SnO2, PEIE, PDINO, PFN-Br, etc.) or a hole transport layer for transporting photogenerated holes (including PEDOT, NiOx, MoO3, etc.). Relatively, the second transport layer 250 can be a hole transport layer or an electron transport layer. That is to say, when the first transport layer 230 is an electron transport layer, the second transport layer 250 is a hole transport layer; when the first transport layer 230 is a hole transport layer, the second transport layer 250 is an electron transport layer. The photogenerated electrons and photogenerated holes generated by the active light-absorbing layer 240 between the two can be transmitted through the corresponding transport layers respectively, so that the photon electrons can migrate to the first microbial group 300, and the photogenerated holes can be captured by the capture agent. This can be referred to Figure 5 It is clearly shown that, where e -is the photogenerated electron, h + The electron transport layer is ZnO, which is the electron transport layer, and the hole transport layer is MoO3. In addition, the electron transport layer is ZnO prepared by spin coating, the spin coating speed is 2000-4000 rpm, and the time is 15-30s; the hole transport layer is MoO3 prepared by high vacuum coating, and the deposition rate is The evaporation thickness is 10 nm.

[0033] Regarding the active light-absorbing layer 240, based on the differences in energy band structure, absorption spectrum, and carrier mobility of different semiconductor materials, the semiconductor materials are screened according to the different environments of the hybrid system and the needs of bacteria. The active light-absorbing layer 240 can be an organic semiconductor donor material including P3HT, PM6, PTB7-Th, etc., or an acceptor material including fullerene acceptors C60, PCBM, ICBA, etc., as well as non-fullerene acceptors Y6, BTP-ec9, L8-BO, etc., among which, for P3HT:P The active light-absorbing layer 240 of CBM and PM6:Y6 systems has a solvent of chlorobenzene or chloroform, a solution concentration of 20:20 mg / mL, a spin coating speed of 1000 rpm, a time of 1 minute, and then an annealing treatment at 120-140°C for 10-30 minutes. The active light-absorbing layer 240 can also be an inorganic semiconductor material, such as a quantum dot material, etc. The solvent is toluene or chlorobenzene, the spin coating speed is 1000 rpm, the time is 1 minute, and the annealing treatment is at 120-140°C for 10-30 minutes.

[0034] By using the above-mentioned sputtering, spin coating, thermal evaporation and other film preparation methods, the photoelectric functional layers such as the bottom electrode 220, the first transmission layer 230, the active light absorption layer 240, the second transmission layer 250 and the top electrode 260 are prepared layer by layer according to the structural design to construct the organic semiconductor film layer.

[0035] As an example, Figure 2(a)-Figure 2(h) As shown, the semiconductor film 200 may be one of the following layer structures, which include, from bottom to top:

[0036] (1) a substrate 210 and an active light-absorbing layer 240 (as shown in FIG. 2( a ) and FIG. 2 ( c ));

[0037] (2) substrate 210, bottom electrode 220 and active light absorbing layer 240 (as shown in FIG2(b) and FIG2(d));

[0038] (3) substrate 210, bottom electrode 220, active light absorbing layer 240 and top electrode 260 (not shown);

[0039] (4) substrate 210, active light absorbing layer 240 and top electrode 260 (not shown);

[0040] (5) substrate 210, bottom electrode 220, first transmission layer 230, active light absorbing layer 240 and second transmission layer 250 (as shown in FIG2(e));

[0041] (6) substrate 210, bottom electrode 220, first transmission layer 230, active light absorbing layer 240, second transmission layer 250 and top electrode 260 (as shown in FIG2 (f) and FIG2 (h));

[0042] (7) substrate 210, bottom electrode 220, active light absorbing layer 240, second transmission layer 250 and top electrode 260 (as shown in FIG2(g));

[0043] (8) substrate 210, bottom electrode 220, first transmission layer 230, active light absorbing layer 240, and top electrode 260 (not shown); and

[0044] (9) Substrate 210, bottom electrode 220, first transmission layer 230 and active light absorption layer 240 (not shown).

[0045] It should be understood that the semiconductor film 200 of the present application may also include other structures besides the above structures (1)-(9), as long as it can complete the photoelectric conversion process and the electron migration process.

[0046] In particular, Figures 2(f) and 2(h) illustrate the inverted and upright structures, respectively, of the semiconductor thin film 200. In the inverted structure, the electron transport layer ZnO is located below the active light absorbing layer 240, and the hole transport layer MoO3 is located above it. Conversely, in the upright structure, the hole transport layer MoO3 is located below the active light absorbing layer 240, and the electron transport layer ZnO is located above it.

[0047] The first microbial group 300 is first inoculated into a growth medium for pre-culture, and then its OD 600 After the pH value exceeds 0.2, the prepared semiconductor film 200 is placed in a growth medium and cultured. After a certain period of time, the artificial photosynthesis system 100 based on microorganisms and semiconductor films is completed. The culture medium is then replaced with a test medium, additives are added, and artificial photosynthesis testing is carried out under light and specific gas atmosphere conditions.

[0048] It should be understood that, depending on the type of substance conversion to be performed, the first microorganisms in the first microbial group (e.g., bacteria, such as anaerobic bacteria, nitrogen-fixing bacteria, and genetically engineered bacteria) should have specific metabolic functions, such as reducing carbon dioxide to acetate, converting nitrogen to ammonium salts, or converting organic matter to small molecules. Such first microorganisms can be engineered with plasmids through synthetic biology methods to obtain microorganisms with specialized functions.

[0049] Microbial culture medium 400 can have different functions. Growth medium contains components for autotrophic growth, such as DSMZ-311 medium for anaerobic bacteria, while test medium contains only basic inorganic salt components, such as M9-MOPS medium for anaerobic bacteria. The gas atmosphere used for artificial photosynthesis testing varies for different microorganisms. For example, the gas atmosphere for anaerobic growth is N2:CO2:H2 = 80:10:10, while the gas atmosphere for testing is N2:CO2 = 80:20.

[0050] In a preferred embodiment, a second microbial group (not shown) may also be grown in the culture medium containing the semiconductor thin film 200. This second microbial group can utilize the products obtained by material conversion by the first microbial group 300 as raw materials for further conversion to obtain additional products, such as medicines and food, thereby further improving the economic benefits of the system.

[0051] The following will further illustrate the preparation of the semiconductor film 200 and the artificial photosynthesis system 100 of the present invention in conjunction with specific embodiments. It should be understood that the implementation of the present invention is not limited to the following embodiments, and any form of adaptation or change based on the present invention will fall within the scope of the present invention.

[0052] like Figure 6 As shown, the preparation method 500 of the artificial photosynthesis system 100 includes the following steps S510-S530.

[0053] (I). S510, preparing the semiconductor thin film 200.

[0054] Example 1

[0055] This embodiment provides a method for preparing an organic semiconductor thin film 200, comprising the following steps:

[0056] (1) The ITO glass substrate, PEN-ITO substrate, and blank glass substrate were cleaned, and the substrates were ultrasonically treated with surfactant, deionized water, isopropyl alcohol, etc. in sequence, and then the surface was blown dry with a nitrogen gun;

[0057] (2) The substrate was surface treated using a plasma cleaner at mid-range for 2 minutes;

[0058] (3) Spin coating ZnO nanoparticles on the clean ITO surface at a rate of 4000 rpm for 30 s;

[0059] (4) Spin coating the organic semiconductor P3HT:PCBM or P3HT as an active layer on the ZnO layer in a concentration range of (5:5, 10:10, 20:20, 30:30 mg / mL) at a spin coating speed of 1000 rpm for 1 min, followed by annealing at 140 °C for 10 min;

[0060] (5) Deposit a MoO3 layer on the surface of the active layer at a deposition rate of Thickness is 10nm;

[0061] (6) Transparent ITO electrode can be sputtered on the surface of the MoO3 layer. The gas atmosphere is argon and the sputtering rate is Thickness is 160nm;

[0062] (7) Through the above steps, glass / P3HT, glass / ITO / P3HT, glass / ITO / P3HT:PCBM, PEN / ITO / P3HT:PCBM, glass / P3HT:PCBM, PEN / P3HT:PCBM and inverted structure organic semiconductor films were obtained, namely glass / ITO / ZnO / P3HT:PCBM / MoO3, PEN / ITO / ZnO / P3HT:PCBM / MoO3, glass / ITO / ZnO / P3HT:PCBM / MoO3 / ITO and PEN / ITO / ZnO / P3HT:PCBM / MoO3 / ITO.

[0063] Example 2

[0064] This embodiment provides another method for preparing an organic semiconductor thin film, comprising the following steps:

[0065] (1) The ITO glass substrate, PEN-ITO substrate, and blank glass substrate were cleaned, and the substrates were ultrasonically treated with surfactant, deionized water, isopropyl alcohol, etc. in sequence, and then the surface was blown dry with a nitrogen gun;

[0066] (2) Deposit a MoO3 layer on the above ITO substrate at a deposition rate of Thickness is 10nm;

[0067] (3) Spin-coating an organic semiconductor P3HT:PCBM solution on the MoO3 layer as an active layer with concentrations of (5:5, 10:10, 20:20, 30:30 mg / mL) at a spin-coating speed of 1000 rpm for 1 min, followed by annealing at 140 °C for 10 min.

[0068] (4) Spin coating a layer of ZnO nanoparticles on the surface of the active layer at a rate of 4000 rpm for 30 s;

[0069] (5) Continue sputtering the transparent ITO electrode on the surface of the ZnO layer. The gas atmosphere is argon and the sputtering rate is Thickness is 160nm;

[0070] (6) Through the above steps, organic semiconductor films with upright structures were obtained, namely glass / ITO / MoO3 / P3HT:PCBM / ZnO / ITO, glass / ITO / P3HT:PCBM / ZnO / ITO, PEN / ITO / MoO3 / P3HT:PCBM / ZnO / ITO, and PEN / ITO / P3HT:PCBM / ZnO / ITO.

[0071] Example 3

[0072] This embodiment provides a method for preparing an independent substrate-free organic semiconductor film 200, comprising the following steps:

[0073] (1) First, prepare an organic semiconductor solution, a chlorobenzene solution of P3HT:PCBM (20:20 mg / mL) and P3HT (20 mg / mL). The solvent can also be chloroform or a mixed solution of chlorobenzene and chloroform.

[0074] (2) Pour a certain amount of aqueous solution into the prepared beaker or culture dish and place it on a horizontal surface;

[0075] (3) Take 10-20 μL of the above organic semiconductor solution and drop it on the surface of the above aqueous solution prepared in advance. Let it stand for 2 minutes to form an organic semiconductor film after the solvent evaporates;

[0076] (4) An independent substrate-free organic semiconductor thin film is obtained, the structure of which is P3HT:PCBM and P3HT.

[0077] (II) S520, pre-culturing the first microbial group 300 in a growth medium within a first time period; and

[0078] (III). S530, adding the semiconductor thin film 200 to the growth medium and co-culturing for a second time period to obtain the artificial photosynthesis system 100 based on the semiconductor thin film 200 and the first microbial group 300.

[0079] Example 4

[0080] This embodiment provides a method for preparing an artificial photosynthesis system of hybridization of an organic semiconductor film and bacteria, comprising the following steps:

[0081] (1) The anaerobic bacteria Sporomusa ovata (S. ovata, ATCC 35899) were first inoculated into the liquid growth medium DSMZ-311 (Table 1 below) at a ratio of 10%, and cultured in a shaking incubator at 34°C in an N2 / CO2 / H2 (80 / 10 / 10) atmosphere for 48 hours. The OD value of S. ovata was recorded at this time. 600 Optionally, the growth medium here can also be a solid agar medium.

[0082] (2) After 48 hours, the organic semiconductor films 200 in Example 1 and Example 2 were placed in the above-mentioned S. ovata culture medium, and continued to be cultured in a shaking table at 34°C in a N2 / CO2 / H2 (80 / 10 / 10) gas atmosphere for 48 hours, and the OD of S. ovata was recorded. 600 Here, for the convenience of description, the S.ovata-ITO / P3HT:PCBM prepared in Examples 1 and 2 (such as Figure 4 As shown, wherein the substrate 210 is omitted) and S.ovata-ITO / ZnO / P3HT:PCBM / MoO3 (as Figure 5 In the following description, an embodiment in which a microorganism group grows on at least one surface of the semiconductor thin film 200 is described in detail.

[0083] (3) After 96 hours, a hybrid system of organic semiconductor film and S. ovata was obtained, and the OD of S. ovata was recorded. 600 The bacterial survival rate at 96 h was recorded as 100%.

[0084] During the bacterial culture process, OD needs to be monitored and recorded throughout the process. 600 value (as shown in Figure 7(a)), and use OD 600 The survival rate of S. ovata was calculated (as shown in FIG7( b )).

[0085] (4) The culture medium of the hybridization system of the organic semiconductor film 200 and S. ovata was replaced with M9-MOPS test medium (Table 2 below), and an electron transfer medium M (such as potassium ferrocyanide, methylene blue, etc.) and a hole trap (such as cysteine Cys, etc.) and other additives were added. Then, the culture medium was placed in a shaking table at 34°C in a N2 / CO2 (80 / 20) gas atmosphere, and an AM 1.5G xenon lamp was used as the light source with a light intensity of 10 mW / cm 2 , 12 hours of light and 12 hours of darkness, then test and record the OD of S.ovata 600 The acetic acid product was sampled and subjected to HNMR quantitative test.

[0086] (5) The bacterial solution subjected to the artificial photosynthesis test for 24 hours was centrifuged at 6000 rpm for 5 min. The supernatant was then collected and sampled for acetic acid production testing. The precipitate was redispersed in new M9-MOPS medium and the artificial photosynthesis test was continued in a shaker at 34°C in an N2 / CO2 (80 / 20) gas atmosphere.

[0087] (6) After the artificial photosynthesis system was subjected to a one-week artificial photosynthesis test, the bacterial liquid was collected and centrifuged at 6000 rpm for 5 minutes. The supernatant was collected and sampled for acetic acid production. The precipitate was collected and resuspended in phosphate buffer and then centrifuged at 10000 rpm for 10 minutes. The precipitate was dehydrated with anhydrous ethanol for 10 minutes and then centrifuged at 10000 rpm for 10 minutes. The precipitate was collected and dried in an air bath at 100°C to obtain the dry weight of S. ovata after the reaction, which can be used to normalize the acetate production of S. ovata, as shown in Figure 7(e).

[0088] (7) HNMR was used to quantify the production of acetic acid, a photosynthetic product of the above system. The internal standard was 3-(trimethylsilyl)-2,2',3,3'-tetradeuteropropionic acid. The sample volume was 50 μL, the internal standard was 5 μL, and the deuterated water was 500 μL. After mixing, they were placed in an NMR tube for testing, as shown in Figures 7(c) and 7(d).

[0089] (8) The quantum efficiency of the acetic acid yield is calculated, as shown in Figure 7(f). Quantum efficiency refers to the ratio of the total number of electrons consumed by the generated acetic acid to the total number of photons input. It takes 8 electrons to reduce two CO2 molecules to one acetic acid molecule. The formula (1) for calculating quantum efficiency is as follows:

[0090] Quantum efficiency (%) = total number of electrons / total number of photons × 100%

[0091] =(8×molar yield of acetic acid) / (total molar number of photons)×100% Formula (1)

[0092] From the above Figure 7(a) to Figure 7(f) The results show that compared with the artificial photosynthesis system 100 without the semiconductor thin film 200 having the electron transport layer ZnO and the hole transport layer MoO3, the artificial photosynthesis system 100 including the semiconductor thin film 200 having the corresponding electron transport layer ZnO and the hole transport layer MoO3 has a higher OD 600 , microbial survival rate, acetic acid production and quantum efficiency, which is due to the presence of the electron transport layer and the hole transport layer can improve the electron transfer efficiency, thereby ensuring the high conversion efficiency of the artificial photosynthesis system.

[0093] Optionally, as described above, in Example 4, the second microbial group can be pre-cultured in a test culture medium and cultured in an M9-MOPS culture medium containing the semiconductor film 200, so that the second microbial group can use the products obtained by material conversion by the first microbial group 300 as raw materials for further conversion to obtain additional products, such as medicines and food, thereby further improving the economic benefits of the system.

[0094] Table 1 DSMZ-311 culture medium

[0095]

[0096]

[0097] Table 2.4 M9-MOPS medium

[0098] <![CDATA[NH4Cl]]> 0.50g <![CDATA[MgSO4·7H2O]]> 0.50g <![CDATA[CaCl2·2H2O]]> 0.25g NaCl 0.918g Trace element solution SL-10 1.00mL <![CDATA[FeSO4]]> 0.002g <![CDATA[K2HPO4]]> 0.348g <![CDATA[KH2PO4]]> 0.227g <![CDATA[Na2HPO4·7H2O]]> 2.145g <![CDATA[NaH2PO4·H2O]]> 0.938g Yeast extract 2.00g <![CDATA[NaHSeO3]]> <![CDATA[10 -7 mol / L]]> <![CDATA[NaHCO3]]> 4.00g Vitamin solution 10.00mL <![CDATA[H2O]]> 1.00L

[0099] The culture medium solutions in Tables 1 and 2 were boiled, cooled to room temperature in an N2 atmosphere, and then sterilized by autoclaving at 121°C for 15 minutes.

[0100] The above description is merely a preferred embodiment of the present application and an illustration of the technical principles employed. Those skilled in the art should understand that the scope of disclosure in this application is not limited to the technical solutions formed by a specific combination of the above-mentioned technical features, but also encompasses other technical solutions formed by any combination of the above-mentioned technical features or their equivalents without departing from the above-mentioned disclosed concepts. For example, a technical solution formed by replacing the above-mentioned features with (but not limited to) technical features with similar functions disclosed in this application.

[0101] In addition, although adopting specific order to describe each operation, this should not be interpreted as requiring these operations to be executed in the specific order shown or in sequential order.Under certain environment, multitasking and parallel processing may be advantageous.Similarly, although comprising some specific implementation details in the above discussion, these should not be interpreted as limiting the scope of the present invention.Some features described in the context of independent embodiment can also be implemented in single embodiment in combination.On the contrary, the various features described in the context of independent embodiment also can be implemented in multiple embodiments individually or in the mode of any suitable subcombination.

[0102] Although the subject matter has been described in language specific to structural features and / or methodological logical acts, it should be understood that the subject matter defined in the appended claims is not necessarily limited to the specific features or acts described above. Rather, the specific features and acts described above are merely example forms of implementing the claims.

[0103] The above describes in detail several embodiments of the present application, but the present application is not limited to these specific embodiments. Those skilled in the art can make various variations and modifications to the embodiments based on the concept of the present application, and these variations and modifications should fall within the scope of protection claimed by the present application.

Claims

1. An artificial photosynthesis system, characterized in that: include: A semiconductor film configured to be capable of photoelectric conversion to generate photogenerated electrons and having biocompatibility; as well as A first microorganism group grows in a culture medium in contact with the semiconductor film and is capable of utilizing the photogenerated electrons generated by the photoelectric conversion to perform material conversion.

2. The artificial photosynthesis system according to claim 1, characterized in that: The semiconductor thin film is one of the following layer structures, which include, from bottom to top: (a) substrate and active light-absorbing layer; (b) the substrate, the bottom electrode and the active light-absorbing layer; (c) the substrate, the bottom electrode, the active light-absorbing layer, and the top electrode; (d) the substrate, the active light-absorbing layer, and the top electrode; (e) the substrate, the bottom electrode, the first transport layer, the active light absorbing layer, and the second transport layer; (f) the substrate, the bottom electrode, the first transport layer, the active light-absorbing layer, the second transport layer, and the top electrode; (g) the substrate, the bottom electrode, the active light-absorbing layer, the second transport layer, and the top electrode; (h) the substrate, the bottom electrode, the first transport layer, the active light absorbing layer, and the top electrode; and (i) the substrate, the bottom electrode, the first transmission layer, and the active light-absorbing layer; The active light-absorbing layer is used to absorb light energy and perform the photoelectric conversion to generate the photogenerated electrons.

3. The artificial photosynthesis system according to claim 2, characterized in that: The first transport layer and the second transport layer are respectively an electron transport layer and a hole transport layer, so as to transport the photogenerated electrons and photogenerated holes respectively.

4. The artificial photosynthesis system according to claim 2, characterized in that: The first transport layer and the second transport layer are respectively a hole transport layer and an electron transport layer, and are used for transporting photogenerated holes and the photogenerated electrons respectively.

5. The artificial photosynthesis system according to claim 1, wherein: The semiconductor film is an active light-absorbing layer film without a substrate.

6. The artificial photosynthesis system according to any one of claims 2 to 5, characterized in that: The active light-absorbing layer is made of one of the following materials: a semiconductor donor material, a combination of a semiconductor donor material and a semiconductor acceptor material, and an inorganic semiconductor material.

7. The artificial photosynthesis system according to claim 6, characterized in that: The semiconductor donor material includes P3HT, PM6, and PTB7-Th; the semiconductor acceptor material includes C60, PCBM, ICBA, Y6, BTP-ec9, and L8-BO; and the inorganic semiconductor material includes a quantum dot material.

8. The artificial photosynthesis system according to claim 3 or 4, characterized in that: The electron transport layer includes ZnO, TiO2, SnO2, PEIE, PDINO and PFN-Br, and the hole transport layer includes PEDOT, NiO X and MoO3.

9. The artificial photosynthesis system according to any one of claims 1 to 5, characterized in that: The microorganisms in the first microbial group are anaerobic bacteria, nitrogen-fixing bacteria and genetically engineered bacteria, and the substance conversion is carbon dioxide reduction, nitrogen fixation and compound conversion respectively.

10. The artificial photosynthesis system according to any one of claims 1 to 5, characterized in that: The first microbial group is in direct contact with at least one surface of the semiconductor film.

11. The artificial photosynthesis system according to any one of claims 1 to 4, characterized in that: The first microbial group grows directly into a biofilm on the surface of the semiconductor thin film on the hard substrate.

12. The artificial photosynthesis system according to any one of claims 1 to 5, characterized in that: A second microbial group is also grown in the culture medium containing the semiconductor film. The second microbial group can use the product obtained by the substance conversion performed by the first microbial group as a raw material for further conversion to obtain additional products.

13. The artificial photosynthesis system according to any one of claims 1 to 5, characterized in that: Additives having a hole-trapping function or an electron-transferring function are also included.

14. A method for preparing an artificial photosynthesis system according to any one of claims 1 to 13, characterized in that: The following steps are involved: preparing the semiconductor thin film; Pre-culturing the first group of microorganisms in a growth medium for a first period of time; as well as The semiconductor film is added to the growth medium and co-cultured for a second period of time to obtain the artificial photosynthesis system based on the semiconductor film and the first microbial group.

15. The method according to claim 14, characterized in that The semiconductor film is prepared by a spin coating method or a high vacuum coating method.

16. The method according to claim 14 or 15, characterized in that The growth medium is a liquid medium or a solid agar medium.

17. The method according to claim 14 or 15, characterized in that The method further includes pre-culturing a second microorganism group in a test culture medium and co-culturing the second microorganism group with the semiconductor film.

18. The method according to claim 14 or 15, characterized in that The method further includes determining different types of the first microbial groups having different metabolic functions through genetic engineering according to the type of substance conversion.

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