Reaction system for coproducing hydrogen and high-value chemicals through electro-catalytic coupling of photovoltaic flow battery

Abstract

The utility model discloses a reaction system for coproducing hydrogen and high-value chemicals through electro-catalytic coupling of a photovoltaic flow battery. The reaction system comprises a photovoltaic power supply system, a flow battery coupling hydrogen production and organic oxidation system and a water electrolysis hydrogen production coupling oxidation system, wherein the flow battery coupling hydrogen production and organic oxidation system and the water electrolysis hydrogen production coupling oxidation system are electrically connected with the photovoltaic power supply system. According to the utility model, green electricity and a green storage system are effectively connected in series, green hydrogen and high-value green chemicals can be produced, and efficient conversion from renewable energy sources to the green chemicals is realized; according to the utility model, a flow battery coupling hydrogen production and organic oxidation system is introduced, all-day long-time operation of the system is realized by utilizing the characteristics of long-time energy storage and high capacity of the flow battery, and a water decomposition hydrogen production and organic oxidation system is introduced to replace a negative electrode reaction, so that efficient utilization of renewable electric energy is realized; the reaction system is wide in applicability, and a new thought is provided for the fields of reasonable utilization of renewable energy sources and green synthesis of organic chemicals.

Description

Technical Field

[0001] The utility model belongs to the field of efficient utilization of renewable energy to prepare green chemicals, and particularly relates to a reaction system for electrocatalytic coupling of a photovoltaic flow battery to co-produce hydrogen and high-value chemicals. Background Technique

[0002] Efficiently converting renewable energy such as solar energy into green chemicals and fuels is expected to replace the use of fossil energy and is a sustainable energy utilization approach. Currently, solar energy can be converted from solar energy to chemical energy through photocatalysis, but its efficiency still needs to be improved. Converting solar energy into green electricity by photovoltaic and then driving electrocatalysis to produce hydrogen and high-value chemicals has been proven to be a feasible method. However, the discontinuity and volatility of renewable energy power generation make the power supply unstable, and the efficient operation of the energy conversion system requires the introduction of an energy storage system.

[0003] The flow battery is a large-capacity long-term energy storage technology. It originated in the 1970s and was proposed by Louis et al. of the National Aeronautics and Space Administration of the United States. It has developed rapidly in the past fifty years and has been proven to be able to effectively perform amplitude modulation and frequency modulation of the power grid. For example, Chunsheng Wang et al. designed a reversible chlorine redox flow battery. The battery starts from electrolyzing aqueous NaCl electrolyte, extracts the generated Cl2 and stores it in carbon tetrachloride for redox, realizing the cost reduction and activity improvement of the flow battery (Nat. Commun. 2022, 13, 1281). However, the application of flow batteries in the system of converting renewable energy into chemical energy has been less studied at present, and the photovoltaic-electrocatalytic system is still the main one. For example, Antoni Llobet et al. used a photovoltaic-electrocatalytic system with [Ru(O)(tda)(py)2] molecular catalyst as the anode and achieved a solar-hydrogen conversion efficiency of 21.2% at neutral pH (ACS Appl. Mater. Interfaces 2020, 12, 50, 55856 - 55864). Xiaodan Zhang et al. reported a two-dimensional nanosheet quaternary metal hydroxide catalyst composed of Ni, Fe, Cr, and Mo elements for electrolyzing seawater in a photovoltaic-electrocatalytic system. This system can operate at a current density of 500 mA cm -2 for 1000 hours at a voltage of 1.82 V (ACS Nano 2023, 17, 5, 4539 - 4550). Although these photovoltaic-electrocatalytic systems have made good demonstrations for the conversion of solar energy to chemical energy, the discontinuity of photovoltaic makes it necessary to adjust the power transmission in the system with a large-capacity energy storage system such as a flow battery, and the system electronic economy of the flow battery also needs to be further improved. Content of the Utility Model

[0004] The present utility model is proposed to optimize the problems existing in the prior art, such as the low efficiency of the green conversion system from renewable energy to chemical energy, and the high cost and low energy utilization rate of the electrochemical energy storage system as a relay. Its purpose is to provide a reaction system for the electrocatalytic coupling of a photovoltaic flow battery to co-produce hydrogen and high-value chemicals.

[0005] The present utility model is realized through the following technical solutions:

[0006] A reaction system for the electrocatalytic coupling of a photovoltaic flow battery to co-produce hydrogen and high-value chemicals, comprising a photovoltaic power supply system and a flow battery coupling hydrogen production and organic oxidation system and an electrolytic water hydrogen production coupling oxidation system electrically connected to the photovoltaic power supply system; the photovoltaic power supply system includes at least one photovoltaic module, and a flow transformer, a flow circuit breaker, and a flow DC power supply are sequentially arranged on the circuit between the photovoltaic module and the flow battery coupling hydrogen production and organic oxidation system; an electrolytic transformer, an electrolytic circuit breaker, and an electrolytic DC power supply are sequentially arranged on the circuit between the photovoltaic module and the electrolytic water hydrogen production coupling oxidation system; the flow battery coupling hydrogen production and organic oxidation system includes at least one flow battery reactor, a flow battery storage mechanism, and a night power supply mechanism; the flow battery storage mechanism includes a flow positive electrolyte storage tank forming a loop with the positive electrode, a pre-charging negative electrolyte storage tank communicated with the liquid inlet of the charging negative flow channel plate, a post-charging negative electrolyte storage tank communicated with the liquid outlet of the charging negative flow channel plate, a pre-discharging negative electrolyte storage tank communicated with the liquid inlet of the discharging negative flow channel plate, a post-discharging negative electrolyte storage tank communicated with the liquid outlet of the discharging negative flow channel plate, and a flow hydrogen gas collecting device communicated with the air outlets of the charging negative electrode and the discharging negative electrode; the night power supply mechanism includes a night transformer, a night circuit breaker, and a night DC power supply connected in sequence; the electrolytic water hydrogen production coupling oxidation system includes at least one electrolytic cell reactor and an electrolytic storage mechanism; the electrolytic storage mechanism includes a pre-electrolyte storage tank communicated with the liquid inlet of the flow channel plate, a post-electrolyte storage tank communicated with the liquid outlet of the flow channel plate, and an electrolytic hydrogen gas collecting device communicated with the air outlet of the electrolytic negative electrode.

[0007] In the above technical solution, when there are multiple photovoltaic modules, the multiple photovoltaic modules are connected in series or in parallel; when there are multiple flow battery reactors, the multiple flow battery reactors are connected in series or in parallel; when there are multiple electrolytic cell reactors, the multiple electrolytic cell reactors are connected in series or in parallel.

[0008] In the above technical solution, the flow battery reactor includes two end plates, and a charging negative electrode, a positive electrode, and a discharging negative electrode are sequentially arranged between the two end plates; sealing plates are arranged between the left end plate and the charging negative electrode and between the right end plate and the discharging negative electrode; sealing plates and diaphragms are arranged between the charging negative electrode and the positive electrode and between the discharging negative electrode and the positive electrode, and the sealing plates are arranged close to the positive electrode; the charging negative electrode includes a charging negative electrode flow channel plate, a charging negative electrode catalytic layer, and a charging negative electrode current collector plate which are sequentially arranged, and the charging negative electrode flow channel plate is arranged close to the left end plate; the positive electrode includes a positive electrode current collector plate and a positive electrode catalytic layer, and the positive electrode catalytic layer is arranged close to the positive electrode side; the discharging negative electrode includes a discharging negative electrode flow channel plate, a discharging negative electrode catalytic layer, and a discharging negative electrode current collector plate which are sequentially arranged, and the discharging negative electrode flow channel plate is arranged close to the right end plate; the end plates, the charging negative electrode, the positive electrode, the discharging negative electrode, and the sealing plates are fixedly connected by bolts.

[0009] In the above technical solution, the charging negative electrode current collector plate, the positive electrode current collector plate, and the discharging negative electrode current collector plate have the same structure, and are all rectangular plate structures. A protrusion for wiring is formed at one end, and a catalytic layer groove is formed in the middle, and the catalytic layer is arranged in the catalytic layer groove; the charging negative electrode flow channel plate and the discharging negative electrode flow channel plate have the same structure, and are all rectangular plate structures. A wiring board for connecting wires is formed by protruding at the top, and an S-shaped coiled liquid flow channel is formed in the middle of the plate body; the sealing plate is a rectangular plate structure, and three rectangular through holes are formed in the middle. The three through holes are, from bottom to top, a raw material mixing chamber, a reaction chamber, and a discharge chamber.

[0010] In the above technical solution, the charging negative electrode current collector plate and the positive electrode current collector plate are respectively electrically connected to the negative electrode and the positive electrode of the liquid flow DC power supply.

[0011] In the above technical solution, the night transformer is electrically connected to the positive electrode current collector plate and the discharging negative electrode current collector plate; the positive and negative electrodes of the night DC power supply are respectively connected to the electrolytic positive electrode current collector plate and the electrolytic negative electrode current collector plate of the electrolytic cell reactor;

[0012] In the above technical solution, the electrolytic cell reactor includes two electrolytic end plates, and an electrolytic positive electrode and an electrolytic negative electrode are arranged between the two electrolytic end plates, and a gasket is arranged between the electrolytic positive electrode and the electrolytic negative electrode; electrolytic sealing plates and flow channel plates are arranged between the electrolytic positive electrode and the electrolytic negative electrode and the electrolytic end plate on the same side, and the electrolytic sealing plates are arranged close to the electrolytic end plates; the electrolytic positive electrode includes an electrolytic positive electrode current collector plate and an electrolytic positive electrode catalytic layer; the electrolytic negative electrode includes an electrolytic negative electrode current collector plate and an electrolytic negative electrode catalytic layer; the electrolytic end plates, the electrolytic positive electrode, the electrolytic negative electrode, the gasket, the electrolytic sealing plates, and the flow channel plates are fixedly connected by bolts.

[0013] In the above technical solution, the structures of the electrolytic positive current collector plate and the electrolytic negative current collector plate are the same as those of the charging negative current collector plate; the electrolytic sealing plate is the same as the sealing plate; the gasket is of a long rectangular frame structure.

[0014] The beneficial effects of the present utility model are as follows:

[0015] The present utility model provides a reaction system for photovoltaic-flow battery-electrocatalytic coupled production of hydrogen and high-value chemicals, effectively connecting the green power and the green energy storage system in series, and capable of producing green hydrogen and high-value green chemicals, realizing the efficient conversion of renewable energy into green chemicals; the present utility model introduces a flow battery coupled hydrogen production and organic oxidation system, utilizes the long-term energy storage and large-capacity characteristics of the flow battery to realize the all-day operation of the system, and introduces a water electrolysis hydrogen production and organic oxidation system to replace the negative electrode reaction, realizing the efficient utilization of renewable electric energy. This system has a wide range of applicability and provides new ideas for the rational utilization of renewable energy and the field of green synthesis of organic chemicals. Description of the Drawings

[0016] Figure 1 is a schematic structural diagram of the present utility model;

[0017] Figure 2 is a schematic structural diagram of the flow battery coupled hydrogen production and organic oxidation reactor in the present utility model;

[0018] Figure 3 is a schematic structural diagram of the water electrolysis hydrogen production coupled oxidation reactor in the present utility model;

[0019] Figure 4 is a scanning electron microscope image of the gold-palladium alloy catalyst in Example 1 of the present utility model;

[0020] Figure 5 is the XRD diagrams of the gold-palladium alloy and gold in Example 1 and Example 2 of the present utility model;

[0021] Figure 6 is the constant current charging diagram of the flow battery under photovoltaic drive in Example 1 of the present utility model;

[0022] Figure 7 is the current-time diagram of ethylene glycol oxidation in the electrolytic cell under photovoltaic drive in Example 1 of the present utility model;

[0023] Figure 8 is the product analysis diagram of ethylene glycol oxidation in the electrolytic cell under photovoltaic drive in Example 1 of the present utility model;

[0024] Figure 9 is the constant current discharge diagram of the flow battery discharge coupled ethylene glycol oxidation in Example 1 of the present utility model;

[0025] Figure 10It is the scanning electron microscope image of the gold catalyst in Embodiment 2 of the present utility model;

[0026] Figure 11 It is the constant current charging diagram of the flow battery under photovoltaic drive in Embodiment 2 of the present utility model;

[0027] Figure 12 It is the current-time diagram of ethylene glycol oxidation in the electrolytic cell under photovoltaic drive in Embodiment 2 of the present utility model.

[0028] Wherein:

[0029] 1. Photovoltaic power supply system;

[0030] 11. Photovoltaic module; 12. Flow transformer; 13. Flow circuit breaker; 14. Flow DC power supply; 15. Electrolytic transformer; 16. Electrolytic circuit breaker; 17. Electrolytic DC power supply;

[0031] 2. Flow battery coupled hydrogen production and organic oxidation system;

[0032] 21. Flow battery reactor; 211. End plate; 212. Charging negative electrode; 2121. Charging negative electrode flow channel plate; 2122. Charging negative electrode catalytic layer; 2123. Charging negative electrode current collector plate; 213. Positive electrode; 2131. Positive electrode current collector plate; 2132. Positive electrode catalytic layer; 214. Discharging negative electrode; 2141. Discharging negative electrode flow channel plate; 2142. Discharging negative electrode catalytic layer; 2143. Discharging negative electrode current collector plate; 215. Sealing plate; 216. Diaphragm;

[0033] 221. Flow positive electrode electrolyte storage tank; 222. Pre-charging negative electrode electrolyte storage tank; 223. Post-charging negative electrode electrolyte storage tank; 224. Pre-discharging negative electrode electrolyte storage tank; 225. Post-discharging negative electrode electrolyte storage tank; 226. Flow hydrogen gas collecting device;

[0034] 231. Night transformer; 232. Night circuit breaker; 233. Night DC power supply;

[0035] 3. Electrolytic water hydrogen production coupled oxidation system;

[0036] 31. Electrolytic cell reactor; 311. Electrolytic end plate; 312. Electrolytic positive electrode; 3121. Electrolytic positive electrode current collector plate; 3122. Electrolytic positive electrode catalytic layer; 313. Electrolytic negative electrode; 3131. Electrolytic negative electrode catalytic layer; 3132. Electrolytic negative electrode current collector plate; 314. Gasket; 315. Electrolytic sealing plate; 316. Flow channel plate;

[0037] 321. Pre-electrolyte storage tank; 322. Post-electrolyte storage tank; 323. Electrolytic hydrogen gas collecting device.

[0038] For those of ordinary skill in the art, without creative efforts, other relevant drawings can be obtained based on the above drawings. Detailed implementation manners

[0039] In order to enable those skilled in the art of this technology to better understand the technical solution of the present utility model, the technical solution of the present utility model will be further described below in conjunction with the drawings in the specification and through specific implementation manners.

[0040] As Figures 1 to 3 shown, a reaction system for electrocatalytic coupling of a photovoltaic flow battery to co-produce hydrogen and high-value chemicals includes a photovoltaic power supply system and a flow battery coupling hydrogen production and organic oxidation system and an electrolytic water hydrogen production coupling oxidation system that are electrically connected to the photovoltaic power supply system;

[0041] The photovoltaic power supply system 1 includes at least one photovoltaic module 11. A flow transformer 12, a flow circuit breaker 13, and a flow DC power supply 14 are sequentially arranged on the circuit between the photovoltaic module 11 and the flow battery coupling hydrogen production and organic oxidation system; An electrolytic transformer 15, an electrolytic circuit breaker 16, and an electrolytic DC power supply 17 are sequentially arranged on the circuit between the photovoltaic module 1 and the electrolytic water hydrogen production coupling oxidation system;

[0042] When there are multiple photovoltaic modules 1, the multiple photovoltaic modules 1 are connected in series or in parallel.

[0043] The flow battery coupling hydrogen production and organic oxidation system includes at least one flow battery reactor 21, a flow battery storage mechanism, and a night power supply mechanism;

[0044] When there are multiple flow battery reactors 21, the multiple flow battery reactors 21 are connected in series or in parallel.

[0045] The flow battery reactor 21 includes two end plates 211, and a charging negative electrode 212, a positive electrode 213, and a discharging negative electrode 214 sequentially arranged between the two end plates 211; a sealing plate 215 is arranged between the left end plate 211 and the charging negative electrode 212 and between the right end plate 211 and the discharging negative electrode 214; sealing plates 215 and diaphragms 216 are arranged between the charging negative electrode 212 and the positive electrode 213 and between the discharging negative electrode 214 and the positive electrode 213, and the sealing plate 215 is arranged close to the positive electrode 213; the charging negative electrode 212 includes a charging negative electrode flow channel plate 2121, a charging negative electrode catalytic layer 2122, and a charging negative electrode current collector plate 2123 arranged in sequence, and the charging negative electrode flow channel plate 2121 is arranged close to the left end plate 211; the positive electrode 213 includes a positive electrode current collector plate 2131 and a positive electrode catalytic layer 2132, and the positive electrode catalytic layer 2132 is arranged close to the side of the positive electrode 213; the discharging negative electrode 214 includes a discharging negative electrode flow channel plate 2141, a discharging negative electrode catalytic layer 2142, and a discharging negative electrode current collector plate 2143 arranged in sequence, and the discharging negative electrode flow channel plate 2141 is arranged close to the right end plate 211; the end plates 211, the charging negative electrode 212, the positive electrode 213, the discharging negative electrode 214, and the sealing plate 215 are fixedly connected by bolts.

[0046] The charging negative electrode current collector plate 2123, the positive electrode current collector plate 2131, and the discharging negative electrode current collector plate 2143 have the same structure, all being rectangular plate structures, with a protrusion for wiring formed at one end and a catalytic layer groove formed in the middle, and the catalytic layer is arranged in the catalytic layer groove; the charging negative electrode flow channel plate 2121 and the discharging negative electrode flow channel plate 2141 have the same structure, all being rectangular plate structures, with a wiring board formed by a protrusion at the top for connecting wires, and an S-shaped coiled liquid flow channel formed in the middle of the plate body; the sealing plate 215 is a rectangular plate structure, with three rectangular through holes formed in the middle, and the three through holes are, from bottom to top, a raw material mixing chamber, a reaction chamber, and a discharge chamber; the diaphragm 216 is used for separating the positive and negative electrolytes and for ion conduction;

[0047] The charging negative electrode current collector plate 2123 and the positive electrode current collector plate 2131 are respectively electrically connected to the negative electrode and the positive electrode of the liquid flow DC power supply 14.

[0048] The flow battery storage mechanism includes a liquid flow positive electrode electrolyte storage tank 221, a pre-charging negative electrode electrolyte storage tank 222, a post-charging negative electrode electrolyte storage tank 223, a pre-discharging negative electrode electrolyte storage tank 224, a post-discharging negative electrode electrolyte storage tank 225, and a liquid flow hydrogen gas collecting device 226;

[0049] A circuit is formed between the liquid flow positive electrode electrolyte storage 221 and the positive electrode current collector plate 2131, and pumps are provided on both the inlet and outlet pipelines of the liquid flow positive electrode electrolyte storage 221; the pre-charging negative electrode electrolyte storage 222 is connected to the liquid inlet of the charging negative electrode flow channel plate 2121 through a pipeline, and a pump and a valve are provided on the connecting pipeline; the post-charging negative electrode electrolyte storage 223 is connected to the liquid outlet of the charging negative electrode flow channel plate 2121 through a pipeline, and a pump and a valve are provided on the connecting pipeline; the pre-discharging negative electrode electrolyte storage 224 is connected to the liquid inlet of the discharging negative electrode flow channel plate 2141 through a pipeline, and a pump and a valve are provided on the connecting pipeline; the post-discharging negative electrode electrolyte storage 225 is connected to the liquid outlet of the discharging negative electrode flow channel plate 2141 through a pipeline, and a pump and a valve are provided on the connecting pipeline; the liquid flow hydrogen gas collecting device 226 is connected to the gas outlet holes of the charging negative electrode 212 and the discharging negative electrode 214.

[0050] The night power supply mechanism includes a night transformer 231, a night circuit breaker 232, and a night DC power supply 233 that are electrically connected in sequence; the night transformer 231 is electrically connected to the positive electrode current collector plate 2131 and the discharging negative electrode current collector plate 2143; the positive and negative poles of the night DC power supply 233 are respectively connected to the electrolytic positive electrode current collector plate 3121 and the electrolytic negative electrode current collector plate 3132 of the electrolytic cell reactor 31.

[0051] The electrolytic water hydrogen production coupled oxidation system 3 includes at least one electrolytic cell reactor 31 and an electrolytic storage mechanism; when there are multiple electrolytic cell reactors 31, the multiple electrolytic cell reactors 31 are connected in series or in parallel.

[0052] The electrolytic cell reactor 31 includes two electrolytic end plates 311 and an electrolytic positive electrode 312 and an electrolytic negative electrode 313 arranged between the two electrolytic end plates 311. A gasket 314 is arranged between the electrolytic positive electrode 312 and the electrolytic negative electrode 313; electrolytic sealing plates 315 and flow channel plates 316 are arranged between the electrolytic positive electrode 312 and the electrolytic negative electrode 313 and the electrolytic end plates 311 on their same sides, and the electrolytic sealing plates 315 are arranged close to the electrolytic end plates 311; the electrolytic positive electrode 312 includes an electrolytic positive electrode current collector plate 3121 and an electrolytic positive electrode catalytic layer 3122; the electrolytic negative electrode 313 includes an electrolytic negative electrode current collector plate 3132 and an electrolytic negative electrode catalytic layer 3131; the structures of the electrolytic positive electrode current collector plate 3121 and the electrolytic negative electrode current collector plate 3132 are the same as the structure of the charging negative electrode current collector plate 2123; the electrolytic sealing plate 315 has the same structure as the sealing plate 215; the gasket 314 is of a long rectangular frame structure. The gasket is used to separate the anode and the cathode to prevent short circuit and for electrolyte transmission; the electrolytic end plates 311, the electrolytic positive electrode 312, the electrolytic negative electrode 313, the gasket 314, the electrolytic sealing plates 315, and the flow channel plates 316 are fixedly connected by bolts.

[0053] The electrolytic storage mechanism includes a front electrolyte storage tank 321, a rear electrolyte storage tank 322, and an electrolytic hydrogen gas collecting device 323;

[0054] The front electrolyte storage tank 321 is connected to the liquid inlet of the flow channel plate 316 through a pipeline, and a pump and a valve are arranged on the connecting pipeline; the rear electrolyte storage tank 322 is connected to the liquid outlet of the flow channel plate 316 through a pipeline, and a pump and a valve are arranged on the connecting pipeline; the electrolytic hydrogen gas collecting device 323 is connected to the gas outlet hole of the electrolytic negative electrode 313.

[0055] The usage method of the present utility model:

[0056] During the day under sunlight, the photovoltaic power supply system supplies power to the charging module composed of the charging negative electrode and the positive electrode in the hydrogen production and organic oxidation system coupled with the flow battery. At this time, hydrogen is produced at the charging negative electrode, and the low-valence ions in the positive electrode electrolyte are oxidized;

[0057] At night, the discharge module composed of the discharge negative electrode and the positive electrode in the hydrogen production and organic oxidation system coupled with the flow battery cooperates with the night power supply mechanism to supply energy to the hydrogen production by electrolyzing water and coupled oxidation system. At this time, the positive high-valence ions in the positive electrode electrolyte of the hydrogen production and organic oxidation system coupled with the flow battery are reduced and an organic oxidation reaction occurs at the discharge negative electrode to produce green chemicals;

[0058] In the hydrogen production by electrolyzing water and coupled oxidation system, organic oxidation occurs at the anode to produce green chemicals and hydrogen is produced at the cathode;

[0059] The photovoltaic power supply system supplies power to the hydrogen production and organic oxidation system coupled with the flow battery and the hydrogen production by electrolyzing water and coupled oxidation system under sunlight during the day.

[0060] Application Example 1

[0061] A reaction system for co-producing hydrogen and high-value chemicals by coupling photovoltaic, flow battery, and electrocatalysis:

[0062] The positive electrode uses graphite felt, and the positive electrode electrolyte uses an electrolyte containing VO 2+ ions. The charging negative electrode uses a Pt charging electrode and a 1M sulfuric acid negative electrode electrolyte; a Nafion117 diaphragm is arranged between the positive electrode and the charging negative electrode; the discharge negative electrode uses a gold-palladium alloy discharge electrode and a 1M potassium hydroxide discharge negative electrode electrolyte containing an ethylene glycol organic substrate;

[0063] The nickel foam conductive substrate loaded with the gold-palladium alloy catalyst is used as the electrolytic positive electrode. The scanning electron microscope image of the gold-palladium alloy catalyst is as Figure 4 shown, and it can be seen that the alloy catalyst is in the shape of nanoparticles. The XRD pattern is as Figure 5As shown, it can correspond well with the PDF standard card, and there is a peak shift phenomenon because Au and Pd form an alloy; the graphite felt conductive substrate loaded with the Pt electrocatalyst is used as the electrolytic negative electrode to form an electrolytic cell reactor;

[0064] During the day when there is sunlight, the photovoltaic module supplies power to the flow battery system and the electrolysis system respectively. Among them, the flow battery system is driven by the photovoltaic module to charge at a constant current of 100 mA cm -2 The charging curve is as shown in Figure 6 As shown, it can be seen that the voltage required for charging is about 1.3 V, and the battery charging capacity is about 4.1 Ah L -1 ; The charging positive electrode VO 2+ ions are oxidized to VO2 + and the water in the negative electrode sulfuric acid-containing electrolyte undergoes a hydrogen evolution reaction; the electrolysis system is driven by the photovoltaic module, and at a voltage of 1.4 V, the anodic ethylene glycol oxidation reaction and the cathodic hydrogen evolution reaction occur. The current-time diagram of the ethylene glycol oxidation reaction is as shown in Figure 7 As shown, it can be seen that the reaction current can be maintained at 300 mA cm -2 ; The product analysis diagram is as shown in Figure 8 As shown, it can be seen that the ethylene glycol electrocatalytic performance in this system is good, and the yield of the product glycolic acid reaches 4.15 mmol cm -2 h -1 , and both the Faraday efficiency and the selectivity are maintained at about 90%;

[0065] When there is no light at night in the system, the flow battery system discharges to supply power to the electrolysis system. Among them, the flow battery system discharges, and the discharging positive electrode VO2 + is reduced to VO 2+ and the ethylene glycol oxidation reaction occurs at the negative electrode. The discharge curve is as shown in Figure 9 As shown, it can be seen that the discharge voltage of the flow battery is about 0.9 V at 100 mA cm -2 , and the battery discharge capacity is about 4.1 Ah L -1 ; The electrolysis system drives the anodic ethylene glycol oxidation reaction and the cathodic hydrogen evolution reaction under the drive of the flow battery.

[0066] Application Example 2

[0067] A reaction system for photovoltaic-flow battery-electrocatalytic coupled production of hydrogen and high-value chemicals:

[0068] The positive electrode uses a graphite felt charging electrode and a positive electrode electrolyte containing VO 2+ ions. The charging negative electrode uses a Ru charging electrode and a 1 M sulfuric acid negative electrode electrolyte; a Nafion117 diaphragm is set between the charging positive electrode and the charging negative electrode; the discharging negative electrode uses a gold-palladium alloy discharging electrode and a 1 M potassium hydroxide negative electrode electrolyte containing an ethylene glycol organic substrate;

[0069] The nickel foam conductive substrate loaded with gold catalyst is used as the electrolytic positive electrode. The scanning electron microscope image of the gold catalyst is as shown in Figure 10 . It can be seen that the gold catalyst is in the form of nanoparticles. The XRD pattern is as shown in Figure 5 , which can be well corresponded to the PDF standard card. The graphite felt conductive substrate loaded with Pt electrocatalyst is used as the electrolytic negative electrode to form an electrolytic cell reactor.

[0070] During the day when there is sunlight, the photovoltaic module supplies power to the flow battery system and the electrolysis system respectively. Among them, the flow battery system is driven by the photovoltaic module to perform constant current charging at 100 mA cm -2 . The charging curve is as shown in Figure 11 . It can be seen that the voltage required for charging is about 1.35 V, and the battery charging capacity is about 4.1 Ah L -1 . The charging positive electrode VO 2+ ions are oxidized to VO2 + , and the water electrolysis hydrogen evolution reaction occurs at the negative electrode with sulfuric acid-containing electrolyte. The electrolysis system is driven by the photovoltaic module, and the ethylene glycol oxidation reaction occurs at the anode and hydrogen evolution occurs at the cathode at a voltage of 1.4 V. The current-time graph of the ethylene glycol oxidation reaction is as shown in Figure 12 . It can be seen that the reaction current can be maintained at 150 mA cm -2 . The product analysis graph is as shown in Figure 8 . It can be seen that the ethylene glycol electrocatalytic performance in this system is good, and the yield of the product glycolic acid reaches 1.83 mmol cm -2 h -1 , and both the Faraday efficiency and selectivity are maintained at about 80%.

[0071] When there is no light at night in the system, the flow battery system discharges to supply power to the electrolysis system. Among them, the flow battery system discharges, and the discharge positive electrode VO2 + is reduced to VO 2+ , and the ethylene glycol oxidation reaction occurs at the negative electrode. The electrolysis system is driven by the flow battery, and the ethylene glycol oxidation reaction occurs at the anode and hydrogen evolution occurs at the cathode.

[0072] It should be noted that, without conflict, the embodiments in the present invention and the features in the embodiments can be combined with each other.

[0073] In the description of the present utility model, it should be understood that the orientation or positional relationship indicated by the terms "center", "longitudinal", "transverse", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as a limitation on the present utility model. In addition, the terms "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first", "second", etc. may explicitly or implicitly include one or more of such features. In the description of the present utility model, unless otherwise stated, the meaning of "a plurality" is two or more.

[0074] In the description of the present utility model, it should be noted that unless otherwise clearly specified and limited, the terms "installed", "connected", "connected to" should be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or an integral connection; it may be a mechanical connection or an electrical connection; it may be directly connected or indirectly connected through an intermediate medium, and it may be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present utility model can be understood through specific circumstances.

[0075] The applicant declares that the above description is only the specific implementation manner of the present utility model, but the protection scope of the present utility model is not limited thereto. Those skilled in the art should understand that any changes or substitutions that can be easily thought of by any person skilled in the art within the technical scope disclosed by the present utility model fall within the protection scope and the disclosure scope of the present utility model.

Claims

1. A photovoltaic liquid flow battery electrocatalytic coupling reaction system for the co-production of hydrogen and high-value chemicals, characterized in that: It includes a photovoltaic power supply system and a flow battery coupled hydrogen production and organic oxidation system and a water electrolysis hydrogen production coupled oxidation system electrically connected to the photovoltaic power supply system; The photovoltaic power supply system (1) comprises at least one photovoltaic module (11), wherein a liquid flow transformer (12), a liquid flow circuit breaker (13) and a liquid flow DC power supply (14) are sequentially arranged on the circuit between the photovoltaic module (11) and the liquid flow battery coupled hydrogen production and organic oxidation system; and an electrolysis transformer (15), an electrolysis circuit breaker (16) and an electrolysis DC power supply (17) are sequentially arranged on the circuit between the photovoltaic module (11) and the water electrolysis hydrogen production coupled oxidation system; The liquid flow battery coupled hydrogen production and organic oxidation system comprises at least one liquid flow battery reactor (21), a liquid flow battery storage mechanism and a nighttime power supply mechanism; The liquid flow battery storage mechanism comprises a liquid flow positive electrode electrolyte storage device (221) forming a loop with the positive electrode (213), a front charging negative electrode electrolyte storage device (222) communicating with the liquid inlet of the charging negative electrode flow channel plate (2121), a rear charging negative electrode electrolyte storage device (223) communicating with the liquid outlet of the charging negative electrode flow channel plate (2121), a front discharging negative electrode electrolyte storage device (224) communicating with the liquid inlet of the discharging negative electrode flow channel plate (2141), a rear discharging negative electrode electrolyte storage device (225) communicating with the liquid outlet of the discharging negative electrode flow channel plate (2141), and a liquid flow hydrogen gas collecting device (226) communicating with the gas outlets of the charging negative electrode (212) and the discharging negative electrode (214); the night power supply mechanism comprises a night transformer (231), a night circuit breaker (232) and a night DC power supply (233) electrically connected in sequence; The water electrolysis hydrogen production coupled oxidation system (3) comprises at least one electrolytic cell reactor (31) and an electrolysis storage mechanism; The electrolytic storage mechanism comprises a front electrolyte storage device (321) connected to the liquid inlet of the flow channel plate (316), a rear electrolyte storage device (322) connected to the liquid outlet of the flow channel plate (316), and an electrolytic hydrogen gas collecting device (323) connected to the gas outlet of the electrolytic negative electrode (313).

2. The photovoltaic liquid flow battery electrocatalytic coupling reaction system for co-production of hydrogen and high-value chemicals according to claim 1, characterized in that: When there are multiple photovoltaic modules (11), the multiple photovoltaic modules (11) are connected in series or in parallel; when there are multiple liquid flow battery reactors (21), the multiple liquid flow battery reactors (21) are connected in series or in parallel; when there are multiple electrolytic tank reactors (31), the multiple electrolytic tank reactors (31) are connected in series or in parallel.

3. The photovoltaic liquid flow battery electrocatalytic coupling reaction system for co-production of hydrogen and high-value chemicals according to claim 1, characterized in that: The liquid flow battery reactor (21) comprises two end plates (211) and a charging negative electrode (212), a positive electrode (213) and a discharging negative electrode (214) arranged in sequence between the two end plates (211); a sealing plate (215) is arranged between the left end plate (211) and the charging negative electrode (212) and between the right end plate (211) and the discharging negative electrode (214); a sealing plate (215) and a diaphragm (216) are arranged between the charging negative electrode (212) and the positive electrode (213) and between the discharging negative electrode (214) and the positive electrode (213), and the sealing plate (215) is arranged close to the positive electrode (213); the charging negative electrode (212) comprises a charging negative electrode flow channel plate (2121), a charging negative electrode catalyst layer (2122) and a discharging negative electrode (214) arranged in sequence. 2) and a charging negative electrode current collecting plate (2123), and the charging negative electrode flow channel plate (2121) is arranged close to the end plate (211) on the left side; the positive electrode (213) includes a positive electrode current collecting plate (2131) and a positive electrode catalyst layer (2132), and the positive electrode catalyst layer (2132) is arranged close to the positive electrode (213) side; the discharge negative electrode (214) includes a discharge negative electrode flow channel plate (2141), a discharge negative electrode catalyst layer (2142) and a discharge negative electrode current collecting plate (2143) arranged in sequence, and the discharge negative electrode flow channel plate (2141) is arranged close to the end plate (211) on the right side; the end plate (211), the charging negative electrode (212), the positive electrode (213), the discharge negative electrode (214) and the sealing plate (215) are fastened and connected by bolts.

4. The photovoltaic liquid flow battery electrocatalytic coupling reaction system for co-production of hydrogen and high-value chemicals according to claim 3 is characterized by: The charging negative electrode current collector plate (2123), the positive electrode current collector plate (2131) and the discharging negative electrode current collector plate (2143) have the same structure, and are all rectangular plate-shaped structures, with a wiring protrusion formed at one end and a catalyst layer groove formed in the middle, and the catalyst layer is arranged in the catalyst layer groove; the charging negative electrode flow channel plate (2121) and the discharging negative electrode flow channel plate (2141) have the same structure, and are all rectangular plate-shaped structures, with a top protrusion forming a wiring board for connecting electric wires, and an S-shaped winding liquid flow channel formed in the middle of the plate body; the sealing plate (215) is a rectangular plate-shaped structure, with three rectangular through holes formed in the middle, and the three through holes are a raw material mixing chamber, a reaction chamber and a discharge chamber from bottom to top.

5. The photovoltaic liquid flow battery electrocatalytic coupling reaction system for co-production of hydrogen and high-value chemicals according to claim 3, characterized in that: The charging negative electrode current collecting plate (2123) and the positive electrode current collecting plate (2131) are electrically connected to the negative electrode and the positive electrode of the liquid flow DC power supply (14) respectively.

6. The photovoltaic liquid flow battery electrocatalytic coupling reaction system for co-production of hydrogen and high-value chemicals according to claim 1, characterized in that: The nighttime transformer (231) is electrically connected to the positive current collecting plate (2131) and the discharge negative current collecting plate (2143); the positive and negative electrodes of the nighttime DC power supply (233) are respectively connected to the electrolysis positive current collecting plate (3121) and the electrolysis negative current collecting plate (3132) of the electrolytic cell reactor (31).

7. The photovoltaic liquid flow battery electrocatalytic coupling reaction system for co-production of hydrogen and high-value chemicals according to claim 1, characterized in that: The electrolytic tank reactor (31) comprises two electrolytic end plates (311) and an electrolytic positive electrode (312) and an electrolytic negative electrode (313) arranged between the two electrolytic end plates (311), a gasket (314) being arranged between the electrolytic positive electrode (312) and the electrolytic negative electrode (313); an electrolytic sealing plate (315) and a flow channel plate (316) being arranged between the electrolytic positive electrode (312) and the electrolytic negative electrode (313) and the electrolytic end plates (311) on the same side thereof, and the electrolytic sealing plate (315) is close to the flow channel plate (316). The electrolysis end plate (311) is arranged; the electrolysis positive electrode (312) includes an electrolysis positive electrode current collector (3121) and an electrolysis positive electrode catalyst layer (3122); the electrolysis negative electrode (313) includes an electrolysis negative electrode current collector (3132) and an electrolysis negative electrode catalyst layer (3131); the electrolysis end plate (311), the electrolysis positive electrode (312), the electrolysis negative electrode (313), the gasket (314), the electrolysis sealing plate (315) and the flow channel plate (316) are fastened and connected by bolts.

8. The photovoltaic liquid flow battery electrocatalytic coupling reaction system for co-production of hydrogen and high-value chemicals according to claim 7, characterized in that: The structures of the electrolysis positive electrode current collecting plate (3121) and the electrolysis negative electrode current collecting plate (3132) are the same as the structure of the charging negative electrode current collecting plate (2123); the electrolysis sealing plate (315) is the same as the sealing plate (215); and the gasket (314) is a rectangular frame structure.

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