Alloy catalyst high-throughput screening method based on droplet printing and image recognition

Abstract

The application discloses an alloy catalyst high-throughput screening method based on droplet printing and image recognition. The method prints multiple metal precursor solutions on an oil phase reaction pool according to a set proportion through a microfluidic droplet printing system to construct a catalyst precursor droplet array with different element proportions, and prepares an alloy catalyst dot matrix with controllable components through electrochemical deposition. The catalyst catalyzes hydrogen evolution reaction under alkaline conditions, hydrogen bubbles generated in the reaction process are captured by a camera and contour features are extracted, and then the volume of the bubbles is calculated to realize automatic quantitative evaluation of the catalytic performance of each catalytic site. The method realizes a high-throughput closed-loop process from catalyst preparation, performance testing to data analysis, has the advantages of simple operation, high screening efficiency, wide component combination space and the like, is suitable for rapid screening and performance optimization of alloy catalysts under a complex component system, and has a wide application prospect in the field of new energy catalytic material research and development.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of high-throughput screening of hydrogen evolution alloy catalysts, and in particular to a high-throughput screening method for alloy catalysts based on droplet printing and image recognition. BACKGROUND

[0002] In the fields of water electrolysis hydrogen evolution reaction (HER) and oxygen evolution reaction (OER), high-throughput preparation and performance screening of catalysts are key technologies for accelerating the development and optimization of new electrocatalytic materials. Noble metals and their derivatives have been considered as efficient catalysts for hydrogen evolution reaction (HER), but their high cost limits their widespread commercialization. Currently, a variety of non-noble metal transition metal-based catalysts have been developed, such as CoNi alloy, FeCoNiWMo high-entropy alloy, and due to the synergistic effect of elements, they exhibit excellent performance. The development of multi-component catalysts usually adopts a one-by-one synthesis and testing method, which is difficult to cope with the vast component combination space in complex systems such as transition metal catalysts and high-entropy alloy catalysts. Electrodeposition as a simple, controllable, and low-cost method for preparing alloy catalysts has good industrial adaptability and has been widely used in high-throughput preparation strategies.

[0003] However, the existing high-throughput electrodeposition method still has many limitations: one common method is to use a microfluidic device design to mix different concentrations of precursor solutions through a microchannel to achieve automatic proportioning and deposition of binary or ternary systems. Although the throughput is improved within a certain range, when more than three elements are involved, the system complexity increases dramatically, making it difficult to cover a wider component space. Another strategy uses a high-throughput spotter to print and disperse the pre-mixed solution, but this process involves multiple steps such as pre-mixing, loading, and transferring, making the process cumbersome. In addition, in the performance testing stage of a large number of catalyst samples, the traditional electrochemical serial testing method (such as linear sweep voltammetry, cyclic voltammetry, etc.) is commonly used to measure each site one by one. This method not only has low testing efficiency and high time cost, but also makes it difficult to realize true parallel matching with the front-end high-throughput preparation technology, greatly limiting the throughput and efficiency of the overall screening process. Therefore, developing a performance evaluation method that combines high-throughput, automation, and direct visual detection of products has become a key problem to be solved in the current high-throughput catalyst screening process. SUMMARY

[0004] In view of the problems of complex preparation process, difficulty in flexible regulation of component ratio and low performance test efficiency in the existing catalyst high-throughput preparation and screening method, the application provides a high-throughput screening method for alloy catalyst based on droplet printing and image recognition. The method uses a microfluidic droplet printing system to print in an oil phase reaction pool, in-situ electrochemical deposition to prepare an alloy catalyst, and an image recognition system to identify bubbles and calculate the volume, so as to realize automatic and high-throughput screening of the performance of the catalyst. The application realizes high-throughput integration of the whole process from catalyst preparation to performance screening, significantly improves the catalyst screening efficiency, reduces the labor and material costs, and has good automation and scalability. The method is suitable for any electrocatalytic reaction system with a gaseous product, can efficiently screen an alloy catalyst with the best element composition, and has a wide application prospect in the development of new energy catalyst materials and the construction of a high-throughput screening platform.

[0005] The technical scheme of the application is as follows:

[0006] The application first provides a high-throughput screening method for alloy catalyst based on droplet printing and image recognition, which comprises the following steps:

[0007] 1) design a metal precursor printing droplet array, wherein the metal precursor printing droplet array is composed of a plurality of droplets, each droplet represents a precursor of a metal element ratio, is obtained by combining a plurality of metal precursor solutions according to a preset ratio, and the element ratio corresponding to each droplet in the array is different;

[0008] 2) according to the metal precursor printing droplet array designed in step 1), set a digital droplet printing path; print in an oil phase reaction pool, specifically:

[0009] 21) select a metal precursor solution, and print by position according to the preset printing amount of each droplet position in the array to obtain a metal precursor droplet array with a single component;

[0010] 22) move the printing nozzle to the cleaning tank for cleaning; then perform the printing of the next metal precursor solution according to step 21);

[0011] 23) repeat step 22) until the printing of all metal precursor solutions is completed to obtain a metal precursor printing droplet array;

[0012] 3) perform electro-deposition treatment on the metal precursor printing droplet array in the oil phase reaction pool to prepare an alloy catalyst array;

[0013] 4) The obtained alloy catalyst array is cleaned and placed in an electrolytic cell containing an alkaline electrolyte to perform hydrogen evolution reaction; the gas bubbles are collected and profile extraction is performed; the gas bubble volume of each catalytic site is calculated to obtain the electrocatalytic performance data of the alloy catalyst, and the alloy catalyst meeting the requirements and the corresponding element ratio are screened.

[0014] According to a preferred scheme of the present application, in step 2), a microfluidic droplet printing platform is used for printing in an oil phase reaction pool; the microfluidic droplet printing platform comprises an external liquid storage container, a cleaning tank and the oil phase reaction pool; each metal precursor solution is respectively contained in the external liquid storage container, and the oil phase reaction pool comprises a container containing an oil phase and a copper substrate carrier for carrying a droplet array at the bottom of the container; the printing head of the microfluidic droplet printing platform is a droplet printing and electrodeposition head, which has a switchable printing nozzle and a graphite electrode.

[0015] Further preferably, the microfluidic droplet printing platform further comprises a three-dimensional motion platform and a pressure control feeding mechanism; the three-dimensional motion platform is used for moving the droplet printing and electrodeposition head in three-dimensional space, and the pressure control feeding mechanism is used for controlling the suction and extrusion of the printing material; the printing nozzle of the droplet printing and electrodeposition head serves as the suction and extrusion channel of the metal precursor solution, and the printing nozzle is connected to the pressure control feeding mechanism through a conduit; the graphite electrode is used for electrodeposition preparation of the alloy catalyst.

[0016] According to a preferred scheme of the present application, the step 3) comprises:

[0017] 31) The printing head is switched to the graphite electrode, the graphite electrode is moved and contacted with the droplet to be electrodeposited in the oil phase reaction pool, the electrodeposition time is set, and the alloy catalyst of the point is formed on the copper carrier;

[0018] 32) The graphite electrode is moved to the cleaning tank for cleaning; and then electrodeposition is performed at the next droplet position;

[0019] 33) Step 32) is repeated until electrodeposition of the metal precursor sites of all element ratios is completed, and finally an alloy catalyst array with multiple element ratios is obtained.

[0020] According to a preferred scheme of the present application, the step 4) comprises:

[0021] 41) The obtained alloy catalyst array is cleaned and placed in an electrolytic cell containing an alkaline solution to perform hydrogen evolution reaction; during the reaction, hydrogen bubbles are generated on the surface of the alloy catalyst and enter the chamber of the gas collection device under ultrasonic assistance; the gas collection device ensures that the bubbles generated by each catalytic site in the reaction time are collected into the respective chambers; wherein the alkaline solution can be KOH solution;

[0022] 42) using the image acquisition system to take images of the hydrogen bubbles generated on each catalytic site;

[0023] 43) using the image processing module to perform bubble recognition and contour extraction on the captured bubble images;

[0024] 44) according to the bubble contour data, obtaining the area of the bubbles on the image, calculating the bubble volume of each catalytic site, and obtaining the electrocatalytic performance data of the alloy catalyst.

[0025] The beneficial effects of the present application are as follows:

[0026] (1) The present application proposes a high-throughput screening method for alloy catalysts based on droplet printing and image recognition. The method combines droplet printing, electrochemical deposition, and image recognition to form a closed-loop high-throughput screening system. The system has both the array characteristics of droplet printing and the adaptability of image recognition. The method has the advantages of simple operation, high automation, and fast screening efficiency, and can flexibly control the element types and ratios of the metal precursor printing array.

[0027] (2) In the preparation of alloy catalyst arrays with multiple element ratios, the microfluidic droplet printing system used in the present application integrates the printing nozzle and graphite electrode in the printing head, allowing continuous printing of different metal precursor solutions and in-situ electrochemical deposition to prepare catalysts. The system has an automatic cleaning function, which avoids cross-contamination between different precursor solutions.

[0028] (3) In the printing of metal precursor printing arrays with multiple element ratios, the metal precursor solution is printed in an oil phase, which is different from the water phase or air printing in the prior art. This avoids changes in the concentration of the metal precursor solution caused by volatilization, thereby ensuring the stability of each droplet and the consistency of the concentration of the metal precursor printing array during electrochemical deposition.

[0029] (4) The present application integrates an image processing module to perform real-time image acquisition and processing of the bubbles generated during the hydrogen evolution reaction of the alloy catalyst array. By recognizing the bubble contours and calculating the bubble volume, the hydrogen production performance of each catalytic site can be directly evaluated, realizing efficient screening of alloy catalysts.

[0030] (5) The present application does not limit the number and ratio of elements in the alloy catalyst, providing a universal method for the preparation and screening of alloy catalysts. BRIEF DESCRIPTION OF DRAWINGS

[0031] Figure 1 Design diagram of metal precursor printing array with multiple element ratios. "Fe x Co y Ni 1-x-y " represents the precursor component ratio of the droplet at the corresponding position, and also serves as the element combination identifier for that catalyst site.

[0032] Figure 2 Fe x Co y Ni 1-x-y Metal precursor printing array construction process schematic.

[0033] Figure 3 Catalytic test bubble collection schematic.

[0034] Figure 4 Catalyst site hydrogen bubble image recognition process schematic. Figure 4 (a) is a schematic diagram of the training and principle of the image recognition algorithm YOLOv8; (b), (c), (d), and (e) are respectively a raw image of a certain site bubble captured by a camera, a real bubble image manually labeled, a reconstructed bubble image, and a difference (IoU represents the area overlap) between the reconstructed bubble and the real bubble.

[0035] Figure 5 Electrocatalytic performance data diagram of the catalyst. DETAILED DESCRIPTION

[0036] The application will be further described below in conjunction with the drawings and examples.

[0037] The application uses a microfluidic droplet printing system, loads a metal precursor printing array path file with multiple element ratios, controls the XYZ axis stepper motor on the three-dimensional moving printing system and the advancement amount of the syringe on the pressure control mechanism, accurately controls the volume and position of the liquid, and obtains an alloy catalyst array with multiple element ratios through program control of the graphite electrode on the array droplet for electrodeposition treatment. In combination with an image recognition system, the image of the bubble generated in the catalytic reaction process is subjected to contour recognition and volume reconstruction, the hydrogen bubble volume of each catalytic site is calculated, and the electrocatalytic performance is evaluated.

[0038] Specifically, the alloy catalyst high-throughput screening method based on droplet printing and image recognition uses a microfluidic droplet printing system to print in an oil phase reaction pool, and in-situ electrochemically deposits to prepare an alloy catalyst.

[0039] As Figure 2 shown, in an embodiment of the application, the microfluidic droplet printing system includes a three-dimensional moving platform, a pressure control feeding mechanism, a droplet printing and electrodeposition head, an external liquid storage container, an oil phase reaction pool, and a cleaning tank. The three-dimensional moving platform includes an X-axis moving mechanism, a Y-axis moving mechanism, and a Z-axis droplet printing and electrodeposition head driving mechanism. The X-axis moving mechanism and the Y-axis moving mechanism are used to realize the movement of the droplet printing and electrodeposition head in the XY plane. The Z-axis droplet printing and electrodeposition head driving mechanism is used to realize the movement of the droplet printing and electrodeposition head in the Z-axis direction.

[0040] The droplet printing and electrodeposition head comprises a switchable printing nozzle and a graphite electrode; the printing nozzle serves as a suction and extrusion channel for the metal precursor solution; the printing nozzle is connected to a pressure control feeding mechanism through a conduit. The pressure control feeding mechanism of the present application is used to regulate the quantitative suction and extrusion of the metal precursor solution; the external liquid storage container is used to store the metal precursor solution, and the types of the metal precursor solution are configured according to the types of the required metal elements according to the prior art, which is not limited by the present application; for example, for the selected metal, a soluble salt solution can be selected as the precursor solution; the oil phase reaction pool comprises a container for containing the oil phase (dimethyl silicone oil is used in the embodiment) and a copper substrate carrier carrying the droplet array; the cleaning tank is used for cleaning the printing nozzle and the graphite electrode, which can contain deionized water.

[0041] As shown in Figure 3 , the method of the present application uses an image recognition system to identify bubbles and calculate the volume. The image recognition system comprises a bubble collection device, an image acquisition device, an image processing module and a data analysis module. The bubble collection device is used to capture the hydrogen bubbles generated at each catalytic site, which is specifically a circular groove array printed by light-cured resin matched with the alloy catalytic array; each circular groove is a chamber corresponding to a catalytic site. Figure 3 The image acquisition device is used to acquire the image of the hydrogen bubbles generated at each catalytic site; the image processing module uses a deep learning algorithm (YOLOv8 image recognition algorithm and bubble shape reconstruction algorithm) to identify and segment the bubble contour of the captured bubble image; the data analysis module calculates the bubble volume of each catalytic site according to the identification result and according to the pre-established bubble area-volume mapping relationship.

[0042] The following describes in detail the high-throughput screening of alloy catalysts based on droplet printing and image recognition of the present application, which comprises the following steps:

[0043] Step one: move the printing nozzle to the external liquid storage container containing the metal precursor solution, adjust the return distance of the injection pump to suck a certain amount of liquid. Then move the printing nozzle to the oil phase reaction pool, place it at the target position of the copper substrate, extrude a certain amount of liquid, wait for the extruded liquid to be placed on the copper substrate, and then move the printing nozzle to the next printing position. After printing the metal precursor liquid array of a single component, move the printing nozzle to the cleaning tank for cleaning. According to the types of the required metal solution components, print a new component liquid array to automatically and high-throughput construct a metal precursor printing array with multiple element proportions.

[0044] Step 2: Control the graphite electrode to contact the metal precursor printing array point by point to complete the electrodeposition process (the graphite electrode and copper substrate support are connected to the electrochemical workstation via wires, the working voltage is 3.4V, and the electrodeposition reaction time is 90s). After the electrodeposition of each catalytic site is completed, the electrode is automatically cleaned and continues to process the next site, finally obtaining an alloy catalyst array with multiple element ratios.

[0045] Step 3: The prepared alloy catalyst array is placed in an alkaline electrolyte (1M KOH) to initiate the hydrogen evolution reaction. Hydrogen bubbles are generated on the catalyst surface and enter the chamber of the gas collection device under ultrasonic assistance. The bubbles are identified and their contours are extracted. The volume of the bubble at each catalytic site is calculated to obtain the electrocatalytic performance data of the alloy catalyst. Based on the required electrocatalytic performance, alloy catalysts and their corresponding element ratios that meet the requirements are selected. The identification of bubbles and the estimation of bubble area can be performed using any image processing algorithm in the prior art that can obtain the bubble contour and estimate the area. This invention does not limit this. In a specific embodiment of this invention, YOLOv8 instance segmentation (YOLOv8-seg) is used to identify individual bubbles in the image. The model outputs a binary mask and a set of corresponding contour points for each target. OpenCV is called to extract the outer contour. Then, the minimum circumcircle is used to fit each contour. The bubble area is obtained from the known scale objects in the image. The bubble volume at each site is obtained according to the pre-established bubble area-volume relationship (obtained in advance by fitting the area and volume relationship of bubbles with known volume and area), generating a catalyst performance map.

[0046] Example 1: Fe x Co y Ni 1-x-y High-throughput screening of alloy catalysts

[0047] The method of the present invention is used to treat Fe x Co y Ni 1-x-y The high-throughput screening of ternary alloy catalysts is carried out using the following steps:

[0048] (1) Design a Fe-Co-Ni ternary component space with a concentration gradient step size of 0.2, such as Figure 1 The triangular array shown has three vertices representing pure Fe, pure Co, and pure Ni, respectively; each dot corresponds to a set of alloy composition Fe. x Co y Ni 1-x-y The Co content increases in equal increments from bottom to top, while the Fe content increases in equal increments from left to right at the bottom edge, and the Ni content decreases in equal increments. Each circle represents a sector pie chart, with sector angles plotted according to the mole fraction of the element (brown = Co, yellow = Fe, green = Ni).

[0049] (2) Preparation of single metal precursor solutions. 1.99 g of ferrous chloride tetrahydrate, 2.38 g of cobalt chloride hexahydrate and 2.38 g of nickel chloride hexahydrate were added to 100 ml of 1 M ammonium chloride solution respectively to obtain three 0.1 M metal precursor solutions, which were stored in three 20 ml glass bottles respectively.

[0050] (3) Take four square boxes containing 100ml of deionized water and use them as cleaning tanks for printing iron precursor solution, cobalt precursor solution, nickel precursor solution and graphite electrode, respectively.

[0051] (4) Place the copper substrate in a plastic box and add 200 cSt dimethyl silicone oil as an oil phase reaction pool to ensure that the liquid printing process on the copper substrate is completed in the oil phase reaction pool.

[0052] (5) Place the metal precursor solution bottle, washing tank, and oil phase reaction tank on the Z-axis platform.

[0053] (7) The layer-by-layer printing of Fe, Co, and Ni metal precursors is completed through program control, such as... Figure 2 As shown, first, Fe precursor solutions are printed to form a triangular array. Then, Co precursor solutions are printed and superimposed on the same coordinate system. Next, Ni precursor solutions are printed and superimposed, ultimately resulting in Fe atoms distributed according to a stoichiometric gradient. x Co y Ni 1-x-y Precursor printing array.

[0054] (8) Control the electrodeposition of each catalytic site on the graphite electrode for 90s, and clean the graphite electrode after each electrodeposition.

[0055] (9) After completing electrodeposition, Fe x Co y Ni 1-x-y The alloy catalyst array was cleaned and transferred into a KOH solution. A bubble collection device was placed above the alloy catalyst array to carry out the hydrogen evolution reaction. Figure 3 ).

[0056] (10) Use a camera to capture bubble images, and use YOLOv8 instance segmentation (YOLOv8-seg) to identify individual bubbles in the image. The model outputs a binary mask and corresponding contour point set for each target, calls OpenCV to extract the outer contour, and then uses the minimum circumcircle to fit each contour. The bubble area is obtained from objects of known scale in the image, such as... Figure 4 As shown in (a) of the diagram. Figure 4 (b) in the image is the original image of the bubble. Figure 4 (c) in the image represents a manually annotated real bubble image and Figure 4(d) the reconstructed bubble mask in (c), Figure 4 (e) shows the coincidence between the reconstructed bubbles and the real bubbles up to 93%, which intuitively shows the consistency of the bubble recognition results in position and quantity with the original image.

[0057] (11) According to the area-volume mapping, the bubble volume data of 21 catalytic sites were obtained, and the catalytic performance map was drawn. As shown in Figure 5 Fe 40–70 Co 30–70 Ni 0–20 The region of Fe 0-25 Co 40-70 Ni 25-60 and Fe 0-10 Co 70-100 Ni 0-30 also showed relatively high HER catalytic activity, and the map clearly defined the preferential amplification strategy.

[0058] The above examples are only exemplary descriptions of the present application and do not constitute a limitation on the scope of protection. Those skilled in the art can make deformation design of multi-component and different concentration step combination without departing from the core idea of the present application, including the extension screening of quaternary and quinary alloy system, which should be covered in the protection scope of the present application.

Claims

1. A high-throughput screening method of alloy catalysts based on droplet printing and image recognition, characterized in that, The method comprises the following steps: 1) designing a metal precursor printing droplet array, the metal precursor printing droplet array is composed of a plurality of droplet arrangements, each droplet represents a proportion of a metal element precursor, which is obtained by combining a plurality of metal precursor solutions in a predetermined proportion, and the element proportions of the droplets in the array are different; 2) setting a digital droplet printing path according to the metal precursor printing droplet array designed in step 1); printing in an oil phase reaction tank, specifically: 21) selecting a metal precursor solution, printing by position according to the predetermined printing amount of each droplet position in the array, to obtain a single-component metal precursor droplet array; 22) moving the printing nozzle to the cleaning tank for cleaning; then printing the next metal precursor solution according to step 21); 23) repeating step 22) until the printing of all metal precursor solutions is completed, to obtain a metal precursor printing droplet array; 3) performing electrodeposition treatment on the metal precursor printing droplet array in the oil phase reaction tank to prepare an alloy catalyst array; 4) washing the obtained alloy catalyst array and placing it in an electrolytic cell containing an alkaline electrolyte to perform hydrogen evolution reaction; Collecting bubbles and performing contour extraction; Calculating the bubble volume of each catalytic site to obtain the electrocatalytic performance data of the alloy catalyst, and screening to obtain the alloy catalyst meeting the requirements and the corresponding element proportion.

2. The high-throughput screening method of alloy catalysts based on droplet printing and image recognition according to claim 1, characterized in that, In step 2), a microfluidic droplet printing platform is used for printing in an oil phase reaction tank; the microfluidic droplet printing platform comprises an external liquid storage container, a cleaning tank and an oil phase reaction tank; each metal precursor solution is respectively contained in the external liquid storage container, the oil phase reaction tank comprises a container for containing oil phase and a copper substrate carrier for carrying the droplet array at the bottom of the container; the printing head of the microfluidic droplet printing platform is a droplet printing and electrodeposition head, which has a switchable printing nozzle and a graphite electrode.

3. The high-throughput screening method of alloy catalysts based on droplet printing and image recognition according to claim 2, characterized in that, The microfluidic droplet printing platform further comprises a three-dimensional motion platform and a pressure control feeding mechanism; the three-dimensional motion platform is used for moving the droplet printing and electrodeposition head in three-dimensional space, and the pressure control feeding mechanism is used for controlling the suction and extrusion of the printing material; the printing nozzle of the droplet printing and electrodeposition head serves as the suction and extrusion channel of the metal precursor solution, and the printing nozzle is connected with the pressure control feeding mechanism through a conduit; the graphite electrode is used for electrodeposition preparation of the alloy catalyst.

4. The high-throughput screening method of alloy catalysts based on droplet printing and image recognition according to claim 2, characterized in that, In step 21), when performing printing by position, the printing nozzle is moved to the oil phase, stopped above the target position of the copper substrate, and the printing nozzle extrudes a certain amount of liquid above the copper substrate; after waiting for the liquid to be extruded, the printing nozzle is lowered in the Z-axis direction, the liquid droplet is placed on the copper substrate, the printing nozzle is lifted again, the liquid droplet is separated from the printing nozzle, and the printing nozzle is moved to the next predetermined printing position.

5. The high-throughput screening method of alloy catalysts based on droplet printing and image recognition according to claim 2, characterized in that, The printing nozzle is a conical glass capillary tube; the oil phase is dimethyl silicone oil, and the cleaning tank contains deionized water.

6. The high-throughput screening method of alloy catalysts based on droplet printing and image recognition according to claim 2, characterized in that, The step 3) comprises: 31) switching the printing head to the graphite electrode, moving the graphite electrode and contacting the droplet to be electrodeposited in the oil phase reaction tank, setting the electrodeposition time, and forming the alloy catalyst at the position on the copper substrate carrier; 32) move the graphite electrode to the cleaning tank to clean the graphite electrode; then proceed to the next droplet position for electrodeposition; 33) repeat step 32) until the electrodeposition of the printing droplet array of metal precursors of all element ratios is completed, finally obtaining the alloy catalyst array of multiple element ratios.

7. The high-throughput screening method of alloy catalysts based on droplet printing and image recognition according to claim 6, characterized in that, The graphite electrode and copper substrate carrier are connected to the electrochemical workstation through wires, the working voltage is 3.4 V, and the electrodeposition reaction time is 90 s.

8. The high-throughput screening method of alloy catalysts based on droplet printing and image recognition according to claim 1, characterized in that, The step 4) comprises: 41) after cleaning, the obtained alloy catalyst array is placed in an electrolytic cell containing an alkaline solution to perform a hydrogen evolution reaction; during the reaction, hydrogen bubbles are generated on the surface of the alloy catalyst and enter the cavities of the gas collection device under ultrasonic assistance; the gas collection device ensures that the bubbles generated by each catalytic site within the reaction time are collected into the respective cavities; 42) use an image acquisition system to take images of the hydrogen bubbles generated on each catalytic site; 43) use an image processing module to perform bubble recognition and contour extraction on the photographed hydrogen bubble images; 44) according to the bubble contour data, the area of the bubble on the image is obtained, the bubble volume of each catalytic site is calculated, and the electrocatalytic performance data of the alloy catalyst is obtained.

9. The high-throughput screening method of alloy catalysts based on droplet printing and image recognition according to claim 8, characterized in that, The gas collection device is a circular groove array printed by light-cured resin matching the alloy catalyst array; each circular groove is a cavity corresponding to a catalytic site.

10. The high-throughput screening method of alloy catalysts based on droplet printing and image recognition according to claim 9, characterized in that, The bubble volume is converted according to the pre-established bubble area-volume mapping relationship.

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