326 results about "Reduction potential" patented technology

The invention relates to the technical field of soil pollution component analysis, and discloses an agricultural soil pollution prediction method. The method comprises the following steps: carrying out soil physicochemical property detection through layered gridding sampling, determining the heavy metal content, the organic matter content and the enzyme activity, and obtaining a pollution characteristic data set; monitoring diffusion characteristics of pollutants by adopting an electrochemical sensing detection array, and generating a migration rule model; a multi-parameter monitoring system is used for detecting the pH value, the oxidation-reduction potential and the ion activity, and a dynamic change sequence is formed; establishing a colloid interface action response matrix, and constructing a pollutant accumulation model; determining the occurrence form and the ion concentration of the pollutants, and generating an interaction map; and finally, constructing an early warning system, and outputting a prevention and control scheme. According to the invention, through cooperative application of multiple analysis and test means, and in combination with interface action mechanism research of pollutants in soil, whole-process intelligent monitoring of soil pollution prediction is realized.

The invention discloses an SND-ED intelligent wastewater treatment deep denitrification system and a control method thereof, and particularly relates to the technical field of wastewater treatment. Nitrification and denitrification reaction environments are provided through the reactor, dissolved oxygen, oxidation-reduction potential and temperature data are collected in real time in cooperation with the data monitoring module, the data are transmitted to the control module, and the control module controls the control module based on an ORP deviation index and a temperature change rate abnormal index. Aeration intensity, aeration time and carbon source dosage are dynamically regulated and controlled through fuzzy logic, synchronous proceeding of nitrification and denitrification is ensured, aeration and carbon source dosage are adjusted according to the dynamic balance state of DO, operation frequency and intensity of an aeration device are optimized through a prediction model based on feedback control, and the carbon source dosage is adjusted. The energy consumption is reduced, and the denitrification efficiency is optimized, so that the intelligent and stable deep denitrification wastewater treatment effect is realized.

The invention provides an intelligent control system and method for aquaculture. The intelligent control system comprises a dissolved oxygen detector, a pH detector, an ammonia nitrogen detector, a redox potentiometer, a structured data front-end processor, an underwater binocular vision observation device, a camera, an unstructured data front-end processor, a cloud processor and front-end equipment. The cloud processor makes a decision according to the information of the structured data front-end processor and the unstructured data front-end processor, and controls the front-end equipment to adjust the operation of the culture pond. According to the aquaculture monitoring system, aquaculture water quality key parameters such as dissolved oxygen, pH value, ammonia nitrogen and oxidation-reduction potential are monitored, aquatic animals are monitored in real time in the aquaculture process, the aquaculture environment is dynamically regulated and controlled, and the intelligence of aquaculture is improved. The intelligent control system for aquaculture can be used as a minimum unit template, is efficient and stable in operation, and facilitates the realization of whole-course real-time monitoring, autonomous regulation and control, multi-link coordinated linkage control and intelligent decision-making of aquaculture through copying and popularization.

The invention provides a carbon emission management monitoring method and device for rice planting in a cold region, and relates to the technical field of carbon emission management monitoring. Vertical three-layer parameters of a soil profile, namely the surface methane concentration, the middle oxidation-reduction potential and the deep organic acid concentration, are collected; the method comprises the following steps: mapping a middle-layer potential into an inhibition coefficient according to a microbial electrochemical principle, further calculating potential uplink electron flux and actual downlink electron sedimentation intensity, identifying an electron transport chain breakage risk through a residual error of the potential uplink electron flux and the actual downlink electron sedimentation intensity, and carrying out nonlinear fusion on the electron transport residual error and environment weights of all layers by adopting a p-norm model. Through the risk amplification coefficient, the superlinear conduction of the local risk to the whole system is realized, the dominant risk layer is accurately positioned based on the comprehensive weight, the differential field management strategy is automatically generated, and finally the closed-loop intelligent management normal form is constructed, and the accurate control of the carbon emission based on the mechanism model is realized.

The invention relates to the field of vanadium redox flow batteries, and discloses a vanadium redox flow battery galvanic pile assembly leak hunting method and system, and the method comprises the following steps: obtaining a reference fluid and chemical parameter distribution in a galvanic pile through constructing a multi-level fluid mechanics model and a chemical reaction kinetic model; collecting and monitoring chemical parameters such as pressure, flow, vanadium ion concentration, oxidation-reduction potential and pH value in the galvanic pile in real time; and performing multi-dimensional feature fusion on the acquired data to generate a data matrix, performing abnormal mode recognition on the data matrix by using a deep learning model of a convolutional neural network and a long-short term memory network, and accurately positioning a leakage position. According to the invention, comprehensive monitoring of fluid and chemical parameters in the galvanic pile is realized, detection requirements of tiny leakage can be rapidly responded, high precision and real-time performance are realized, and effective technical support is provided for safe operation of the vanadium redox flow battery.

The invention discloses a circuit board wastewater heavy metal removal method and system, and the method comprises the steps: monitoring the concentration and valence distribution of heavy metal ions in circuit board wastewater in real time, and generating wastewater heavy metal form distribution characteristics in combination with oxidation-reduction potential and pH value; based on wastewater heavy metal form distribution characteristics, adjusting an oxidation-reduction environment to generate heavy metal ion enriched wastewater; the method comprises the following steps: introducing heavy metal ion enriched wastewater into an electric flocculation reactor, applying a periodic electric field through a programmable pulse power supply to dissolve an aluminum or iron anode to release a multi-core hydroxyl complex, and carrying out a co-precipitation reaction with heavy metal ions to generate a flocculating constituent suspension; and introducing the flocculating constituent suspension into a rotational flow clarification and separation device, realizing mud-water separation through centrifugal sedimentation and inclined plate separation, outputting supernate, discharging the supernate after reaching the standard, and recovering precipitated sludge rich in heavy metals. By utilizing the embodiment of the invention, efficient breaking and separation of the complex-state heavy metals can be realized, and good environmental benefits and resource values are achieved.

The embodiment of the invention relates to a method for initiating in-situ polymerization of an electrolyte solution through electrochemical induction. A solvent of the electrolyte solution comprises cyclic ether molecules and halogen atom substituted ethylene carbonate molecules; the method comprises the following steps: carrying out constant-current charging on a battery to a set voltage, and carrying out constant-voltage charging for a specific time under the set voltage, so that halogen atoms of halogen atom substituted ethylene carbonate molecules are removed under the reduction potential of the negative electrode side of the battery to generate free radical sites, two molecular structures after halogen atoms are removed are mutually combined through the free radical sites to form a dimer, the dimer is migrated to the positive electrode side in an electrolyte solution, dehydrogenation reaction is carried out under the action of oxidation potential applied to the positive electrode side, and in-situ ring-opening polymerization reaction of cyclic ether molecules is initiated through removed hydrogen ions; therefore, in-situ polymerization solidification of the electrolyte solution is realized under the condition that a conventional initiator is not contained.

The invention relates to a method for improving solar hydrogen production efficiency of a polar heterojunction material. The method comprises the following steps: firstly, selecting a first polar two-dimensional semiconductor with asymmetric upper and lower layer elements, and coupling and stacking the first polar two-dimensional semiconductor and a second two-dimensional semiconductor through Van der Waals force to form a polar heterojunction; the intrinsic electric field, the vacuum energy level difference and the energy band arrangement of the polar heterojunction are regulated and controlled by turning polarity orientation and applying biaxial strain; under the illumination condition, the intrinsic electric field drives photo-induced electrons and hole space separation, and the vacuum energy level difference enables the oxidation or reduction potential of water to be matched with the energy band boundary, so that the condition of photocatalytic full decomposition of water is met, and the solar hydrogen production efficiency is further improved. Taking a polar heterojunction as an example, the first principle calculation shows that the solar hydrogen production efficiency of the heterojunction is remarkably improved under the regulation and control of an intrinsic electric field and biaxial strain; the method has universality and can be popularized to other two-dimensional polar heterojunction photocatalytic systems.

The invention belongs to the technical field of environmental pollution treatment, and particularly relates to a nitrogen-doped carbon nanotube confinement composite material as well as a preparation method and application thereof. Compared with the prior art, the preparation method has the advantages that the cheap nitrogen source and transition metal salt are used as raw materials, the nitrogen-doped carbon nanotube-coated iron carbide confinement material is creatively synthesized in one step by regulating and controlling the cracking temperature, the metal nanoparticles are effectively coated in the carbon nanotubes, and the preparation method is simple to operate and high in yield. The prepared material has the advantages of large specific surface area, rich catalytic active sites, efficient electron transfer capability, strong magnetism, convenience in recovery and the like, so that the nitrogen-doped carbon nanotube confinement composite material can effectively improve the electron transfer capability of the material, reduce the binding energy between the material and persulfate, and improve the catalytic activity of the material. A reaction system mainly activates persulfate through a free radical path to generate sulfate free radicals and hydroxyl free radicals with higher oxidation-reduction potential, so that perfluoro and polyfluoroalkyl substances are effectively degraded.

The invention relates to a method and a system for reversibly regenerating an inactivated carbon dioxide reduction electrode based on electro-catalysis, which comprises the following steps: firstly, controllably removing pollutants on the surface of the electrode by reversely applying an oxidation potential, and then introducing an electroplating solution containing metal ions and applying a dynamic reduction potential; metal nanoparticles are deposited on active sites on the surface of the catalyst in situ, and the active sites are reconstructed and optimized. According to the method, the initial catalytic performance of the electrode can be basically recovered, the catalytic activity can be recovered, the operation process is compatible with the continuous production requirement, and a core guarantee is provided for efficient and continuous industrial application of the electrocatalytic carbon dioxide reduction technology.

The invention discloses an establishing method, a monitoring method and an adding method of a monitoring model for the concentration of hydrochloric acid in an etching solution. The establishing method of the monitoring model for the concentration of hydrochloric acid in the etching solution comprises the following steps: acquiring sample data; calculating each coefficient value in a pre-established multivariate polynomial regression model according to the sample data to obtain a regression model; obtaining verification data, taking the temperature, the oxidation-reduction potential, the hydrochloric acid concentration and the Cu < 2 + > concentration in the verification data as the input of the regression model, and outputting the predicted value of the conductivity; calculating the closeness degree of the predicted value of the conductivity and the actual value of the conductivity in the verification data; when the calculated closeness degree is smaller than a preset threshold value, recalculating each coefficient value in the regression model until the closeness degree is greater than or equal to the preset threshold value; and when the calculated closeness degree is greater than or equal to a preset threshold value, taking the obtained regression model as a hydrochloric acid concentration monitoring model.

The invention provides a digital production supervision method and system, belongs to the field of computers, and aims to solve the problems of high rework rate and low efficiency caused by the fact that optical inspection or chemical analysis often depends on cleaned quartz pieces due to incomplete cleaning of cracks and residual metal and the like and the optimal correction opportunity is missed once the problems are found. The method comprises the steps that in the stage of cleaning a hot-worked quartz workpiece, a cleaning formula is automatically matched based on information of the quartz workpiece, and the cleaning formula comprises a cleaning solution ratio and a cleaning time-temperature control curve; state change parameters of cleaning liquid in the cleaning tank are obtained in real time, wherein the state parameters of the cleaning liquid comprise conductivity and oxidation-reduction potential; and evaluating the quality defect of the quartz workpiece based on the state change parameter of the cleaning fluid.

The invention discloses a method for preparing a sodium electric precursor by a redox control potential method. According to the invention, the oxidation-reduction electrode is arranged on the reaction kettle to monitor the oxidation-reduction potential of the reaction system in real time, and different potential control is realized by controlling the purity of nitrogen and other mixed gases in the reaction kettle or the dosage of an oxidation-reduction agent added into the reaction kettle; the primary and secondary particle morphology, the specific surface area and the product compaction of the product can be effectively controlled, and precursors with different physical and chemical indexes can be prepared according to different potentials. According to different characteristics of the precursor, the sintered positive electrode material has different electrochemical properties, such as higher electrochemical rate capability, gram volume and cycle performance, so as to meet application requirements of different products.

The invention provides a wet desulphurization oxidation air adjusting system and method with dual-mode verification feedback. A slurry storage tank is connected with a reactor through a sampling unit; the liquid storage bottle is filled with an iodine standard solution and a sodium thiosulfate standard solution, and is connected to the reactor through a hose and a precise injection pump; an oxidation-reduction electrode is inserted into the reactor; and the upper computer measures the oxidation-reduction potential of the solution in the reactor through the oxidation-reduction electrode so as to judge the titration end point and the consumption of the consumed titration standard solution, and inverts the concentration of sulfite ions in the desulfurization slurry. The upper computer is also connected with a dissolved oxygen analyzer to detect the concentration of dissolved oxygen in the slurry in the slurry storage tank; and mutual verification with the concentration of sulfite ions is carried out to realize dual-mode feedback regulation and control of the oxidation system. According to the invention, the complex nonlinear relationship and time dependence of each measurement parameter can be effectively captured, the accuracy of continuous and automatic measurement of sulfite ions in the desulfurization slurry is realized, and the precision is ensured.

The invention discloses a method for preparing low-chromium ammonium polyvanadate, which comprises the following steps: pretreating an impurity removal solution to ensure that the turbidity of the impurity removal solution is not more than 200UTN; adding an oxidizing agent into the pretreated impurity-removed liquid for oxidation to obtain a purified liquid; the purified liquid is subjected to acidic ammonium salt vanadium precipitation, and low-chromium ammonium polyvanadate is obtained; wherein the impurity removal liquid is obtained by selectively reducing sodium vanadium solution and removing chromium and silicon; in addition, different oxidation processes are selected based on the oxidation-reduction potential, the pH value and / or the chromium concentration of the impurity removal liquid. According to the method, different oxidation measures need to be adopted for impurity removal liquid with different properties, so that the oxidation efficiency is improved, the oxidation cost is reduced, and the quality of vanadium precipitates is improved. Different oxidation methods are designed by utilizing the reaction characteristics of chromium and different oxides and combining the pH value of a solution and the oxidation-reduction potential. The method has the characteristics of high oxidation efficiency, low oxidation cost, good vanadium product quality, high vanadium precipitation rate, easy determination of parameter boundaries and strong operability.

The invention relates to the technical field of disinfectants, in particular to a production method of a low-corrosion chlorine dioxide disinfectant, which comprises the following steps: dropwise adding a sodium hydroxide solution, monitoring the pH value, adjusting the pH value to 8-10, maintaining stirring for 5 minutes, checking solubility and temperature, collecting precipitate particles, and filtering to remove the precipitate particles to obtain an alkaline mixed solution. According to the invention, the pH value is monitored and regulated to an alkaline interval to execute solubility inspection, so that the property control of the mixed solution is realized; on the basis of combined treatment of nanometer titanium dioxide photocatalysis and radio frequency discharge, the content of free radicals is multiplied, and the oxidation activity is improved; a silane coupling agent is combined to treat nano zirconium oxide and put into a system, the temperature is adjusted, the dispersion state is monitored, and the dispersion stability is guaranteed; the pH value and the oxidation-reduction potential are continuously monitored, foam separation and the chlorine content are controlled, and the quality of an intermediate solution is ensured; regulating and controlling the adding amount and the pH value of hydrochloric acid, monitoring gas escape, and screening out impurities to obtain a high-purity isolate.

The invention discloses an electrochemical microscopic imaging analysis method based on a fluorescence signal, which comprises the following steps of: constructing a fluorescence response electrochemical signal instrument by combining electrochemistry with a fluorescence microscope, and observing the redox potential of K3 [Fe (CN) 6] by taking a terpyridyl ruthenium (Ru (bpy) 32 +) / potassium ferricyanide (K3 [Fe (CN) 6]) fluorescence system as a research object. Influences of electrochemical behaviors on fluorescence signals are deeply explored, and the relationship between fluorescence signal changes and electric signal changes is revealed. According to the present invention, the combination of the electrochemical technology and the fluorescence signal is achieved, the disadvantage of the poor spatial-temporal resolution of the electrochemiluminescence is made up, the new dimension capable of being regulated and controlled by the electrical parameter is provided for the fluorescence imaging, and the Faraday current and the non-Faraday current can be completely reflected by the fluorescence signal. Therefore, the method has wide application value in the aspects of exploring the conductivity of the nano material and the like.

The present invention belongs to the field of vanadium element analysis and testing, and specifically relates to a method for testing vanadium content and vanadium valence. The testing method of the present invention comprises the following steps: adding a buffer solution to an excess oxidant solution to obtain a standby solution; adding a vanadium-containing electrolyte to be tested with a volume of V to the standby solution, standing, and obtaining an intermediate solution containing excess oxidant and pentavalent vanadium ions; using a potentiometric titrator to add a titrant to the intermediate solution until two sudden jump points appear; the first sudden jump point is a sudden jump in the reduction potential of the excess oxidant, and the volume of the titrant consumed corresponding to the reduction of the excess oxidant is V1; the second sudden jump point is a sudden jump in the reduction potential of pentavalent vanadium, and the total volume of the titrant consumed at this time is V2, and the volume of the titrant consumed corresponding to the reduction of pentavalent vanadium ions to tetravalent vanadium ions is V2-V1; the vanadium content and vanadium valence are calculated by formula. The detection method of the present invention is simple, fast and accurate.

The invention discloses a method for preparing low-chromium ammonium metavanadate, which comprises the following steps: adding an oxidizing agent into an impurity removal liquid for oxidation to obtain an oxidation liquid; carrying out deep desiliconization on the oxidized liquid to obtain a purified liquid; carrying out alkalescence ammonium salt vanadium precipitation on the purified liquid to obtain ammonium metavanadate; wherein the step of adding the oxidizing agent into the impurity removal liquid for oxidation comprises the substeps of selecting a first type of oxidizing agent or a second type of oxidizing agent based on the oxidation-reduction potential and the chromium concentration of the impurity removal liquid; the impurity removal liquid is obtained after the sodium modified vanadium liquid is subjected to selective reduction and chromium-silicon co-removal. According to the method, different oxidation measures are adopted for impurity removal liquids with different properties to improve the oxidation efficiency, reduce the oxidation cost and improve the quality of vanadium precipitates, and the method has the characteristics of high oxidation efficiency, low oxidation cost, good desilicication effect and good vanadium product quality.

The invention provides an earth surface matrix sensor based on a hyperspectral technology and a monitoring method, and the sensor comprises a sensor module which is used for extending into a stratum through a housing; the hyperspectral module extends into the stratum through the shell; the communication module is in communication connection with the sensor module and the hyperspectral module; the terminal module is in communication connection with the communication module and stores a plurality of association relationships between hyperspectral curve characteristics and surface matrix physicochemical property parameters (moisture, salinity, temperature, acidity and alkalinity (pH), oxidation-reduction potential (Eh) and the like), and each association relationship corresponds to a preset region type; the terminal module obtains hyperspectral information measured by the hyperspectral module; the terminal module determines an association relationship corresponding to the stratum according to a region type corresponding to the stratum; and the terminal module completes surface matrix monitoring of the stratum according to the hyperspectral information, the association relationship and the surface matrix physicochemical property parameters.

The invention discloses a method for preparing 5N selenium powder, which specifically comprises the following steps: carrying out oxidation treatment on a crude selenium raw material to be treated to obtain selenium dioxide; dissolving the obtained selenium dioxide at normal temperature to obtain a seleninic acid solution; and carrying out cascade reduction reaction on the obtained seleninic acid solution under the action of an external magnetic field to obtain nano-scale selenium powder, and washing and drying the nano-scale selenium powder to obtain the 5N selenium powder. According to the method, the oxidation-reduction potential is controlled to rise in a stepped manner, and the external magnetic field is used for assistance, so that the oxidation-reduction reaction of selenium is adjusted, forward proceeding of the selenium reduction reaction is promoted, the whole preparation process is short, the selenium purity is high, and the direct yield of selenium is high.

The invention discloses a mechanical and photochemical fluid polishing integrated auxiliary machining platform and a combined polishing method. The platform comprises a rack, a workpiece transfer mechanism used for clamping and moving a workpiece, a mechanical fluid polishing module and a photocatalysis detection feedback module. The mechanical fluid polishing module comprises a dual-purpose polishing groove body, a mechanical polishing assembly and a photocatalytic fluid polishing assembly. The shading area is arranged in the photocatalytic fluid polishing chamber, the oxidation-reduction potentials inside and outside the shading area are detected respectively, the optical excitation ORP value is obtained by solving the difference, the optical excitation ORP value is maintained in an ideal interval by adjusting the ultraviolet light intensity, and the whole photocatalytic fluid polishing process is kept efficient and reliable; due to the fact that the optical excitation ORP eliminates the influence on the oxidability of original substances which contribute slightly to workpiece surface oxidation in the polishing solution, the increment of hydroxyl free radicals generated due to photocatalysis can be accurately measured, and the control accuracy of the photocatalytic fluid polishing process is improved.

The invention relates to a heavy metal removal method for constructing a micro electric field based on cooperation of metal self-corrosion and ion confinement. The heavy metal removal method comprises the following steps that metal with self-corrosion performance serves as an anode, a copper-iron Prussian blue frame material electrode with an ion confinement structure serves as a cathode, heavy metal wastewater serves as electrolyte, and a micro electric field with the energy self-supply characteristic is constructed; and carrying out electrochemical reaction to limit the heavy metal ions in the cathode framework material so as to remove the heavy metal in the wastewater. Compared with the prior art, by constructing the micro electric field with the energy self-supply characteristic and combining the metal iron anode with the negative oxidation-reduction potential and the copper-iron Prussian blue cathode with the ion confinement structure, efficient selective adsorption and stable curing of the heavy metal ions are achieved, and dependence on an external power source or a light source is not needed.

The application discloses an electro-catalytic oxidation system and method and an ecological joint treatment method for in-situ remediation of water body sediments, which utilizes an intelligent pulse power controller to perform intermittent pulse electro-catalytic oxidation on the bottom mud at the water bottom, generates hydroxyl radicals through in-situ catalysis of an anode to degrade organic pollutants of the bottom mud, generates micro-bubbles in the interstices of the bottom mud through the electrolysis of water to improve the oxidation-reduction potential, and further reserves time for the soluble pollutants in the interstitial water of the bottom mud to sufficiently diffuse to the surface of the electrode, so as to avoid energy waste caused by concentration polarization. Through reverse power supply, the polarity of the anode and the cathode is instantaneously reversed, trace amounts of acidic substances and gas generated through in-situ electrolysis are utilized to strip off the calcium and magnesium scale attached to the surface of the cathode, and manual cleaning and maintenance under water are realized. In combination with the planting of submerged plants on the treated bottom mud, ecological joint treatment is realized, the root system of the submerged plants is utilized to perform long-term ecological fixation and water purification on the treated sediments.

The present application provides a kind of biogas slurry chemical oxygen demand online monitoring method and system, the method comprises: obtaining the current characteristic data of biogas slurry, the characteristic data includes multiple in dissolved oxygen, turbidity, oxidation-reduction potential and conductivity;The current characteristic data of the biogas slurry is input into least square regression model, and the current chemical oxygen demand predicted value of the biogas slurry output by the least square regression model is obtained;The least square regression model is obtained by training by taking the characteristic data sample of the biogas slurry as characteristic variable, and taking the measured value of the chemical oxygen demand corresponding to the biogas slurry as target variable.The present application realizes the rapid, low-cost detection of biogas slurry chemical oxygen demand by real-time monitoring of multiple characteristic data, constructing multi-parameter fusion partial least square regression prediction model.

The invention discloses application of an anode material in improvement of oxidation-reduction potential and an electrochromic device, and belongs to the technical field of electrochromic materials. The general formula of the anode material is # imgabs0 #, wherein R5 and R10 are independently selected from any electron withdrawing group; r11 and R12 are independently selected from H or any electron withdrawing group; r1, R2, R3, R4, R6, R7, R8 and R9 are independently selected from H, F, Cl, Br, I, CN, NO2, alkyl or alkoxy. Compared with a conventional anode material, the anode material has the advantages that the electron obtaining capacity is weakened, the electron losing capacity is enhanced, the potential difference absolute value of an electrochromic solution prepared from the anode material and 4, 4 '-dipyridyl is increased, the transmittance of a device in an initial state is improved, and the response time is shortened.

The present invention provides a kind of dilute solution manufacturing device, trace addition to the first liquid such as ultrapure water, the second liquid containing conductivity imparting substance or oxidation-reduction potential adjustment substance, can stably manufacture the dilute solution of specified concentration. Dilute solution manufacturing device by adding the second liquid containing at least one of conductivity imparting substance and oxidation-reduction potential adjustment substance to the first liquid to manufacture the dilute solution of the second liquid, wherein, with: first pipe (1), flow through the first liquid;Pump (6), via second pipe (5) to the first pipe (1) inside the second liquid is added;Degassing pipe (8), from the pump (6) degassing;Water quality sensor (11), by conductivity meter, resistivity meter or oxidation-reduction potential meter is constituted;And control device (12), when the water quality detection value of the water quality sensor (11) is above the specified value, open degassing valve (9).

A photoelectric conversion element 100 according to the present disclosure comprises a first electrode 2, a photoelectric conversion layer 4 containing a perovskite compound, and a second electrode 6. The perovskite compound includes Sn. The photoelectric conversion layer 4 further contains a metal element and a halogen element present in a near-surface region that includes a surface facing the second electrode 6. The metal element has a standard oxidation-reduction potential that is more negative than that of Sn4+.

A metal-organic framework according to the present invention provides a metal-organic framework satisfying chemical formula 1. (Chemical formula 1) M+COO--(CH2)n- COO-M+ (M is a metal having a standard reduction potential of -0.8 V to 1.8 V, and n is an integer between 2 and 15.)