Electrode surface electro-catalysis process detection system based on transient Raman spectrum

Abstract

The invention relates to an electrode surface electro-catalysis process detection system based on transient Raman spectrum, and belongs to the technical field of Raman spectrum. Comprising a circuit part and a transient Raman spectrum testing part, the circuit part comprises a signal generator, an electrochemical workstation, a computer, a digital oscilloscope and a resistor, and the transient Raman spectrum testing part comprises a pulse delayer, an in-situ Raman cell, an objective lens, a doublet lens, a charge-coupled device, a silver mirror, a narrow-band optical filter and a Raman optical filter. The system has excellent adjustability and usability, Raman spectrum signals of reaction intermediates generated in the electrochemical reaction process under the action of electric pulses are detected through nanosecond laser pulses, the dynamic process of the electrocatalytic reaction can be accurately monitored and analyzed through the system, and a powerful tool is provided for studying the electrochemical reaction mechanism.

Description

Technical Field

[0001] The invention belongs to the technical field of Raman spectroscopy, and in particular relates to an electrode surface electrocatalytic process detection system based on transient Raman spectroscopy. Background Art

[0002] Electrocatalytic reactions play a vital role in many fields, especially in energy conversion, storage and environmental protection, such as fuel cells, water electrolysis to produce hydrogen and carbon dioxide reduction. However, the complexity of electrocatalytic reactions makes it difficult to deeply understand their reaction mechanisms and kinetic behaviors, especially the generation, transformation and diffusion of electrochemical reaction intermediates occurring on the electrode surface. These processes are often accompanied by rapid exchange of matter and energy, especially the evolution of reaction intermediates occurring on a short time scale, which directly affects the electrocatalytic performance and reaction efficiency. Therefore, accurately detecting the behavior of these reaction intermediates has become the key to understanding the mechanism of electrocatalytic reactions.

[0003] In the prior art, Raman spectroscopy, as a non-contact, non-destructive analytical tool, has been widely used in materials science and electrochemical reaction research. Raman spectroscopy can provide important information on the chemical composition, molecular structure and bonding state of the research object by detecting molecular vibration modes. However, traditional Raman spectroscopy technology has the problem of insufficient spatial resolution and time resolution, and it is difficult to effectively observe the reaction process in a short period of time, especially in electrocatalytic reactions, the generation and disappearance of reaction intermediates are transient, often occurring on a nanosecond or shorter time scale. In order to better detect the dynamic behavior in these electrocatalytic processes, it is necessary to combine time-resolved Raman spectroscopy technology with electrochemical methods to capture the generation and evolution of reaction intermediates at a higher time resolution. In addition, the complexity of the electrode surface in electrochemical reactions also requires the need to distinguish and detect reaction intermediates in different spatial regions. The electric field near the electrode surface, the diffusion of reactants, the generation of products, and the distribution of current density may all lead to different local reaction behaviors. Therefore, in-depth research on electrocatalytic reactions requires not only time-resolved analytical methods, but also high-precision measurement of the three-dimensional spatial information of the electrode surface and its vicinity. This demand has prompted researchers to develop detection systems that can achieve both high temporal resolution and high spatial resolution.

[0004] The double layer is formed during the reaction process of the electrochemical reaction system. The formation of the double layer is caused by the interface effect between the electrode and the electrolyte. It plays a key role in the electrocatalytic reaction, especially in the adsorption and diffusion of reactants and the formation of intermediates. The electric field changes, ion concentration distribution and local potential difference near the electrode surface directly affect the kinetic behavior of the electrocatalytic reaction. The existence of the double layer means that the ion distribution near the electrode surface is closely related to the external electric field. These factors cause the electrocatalytic reaction to show significant spatial inhomogeneity in the area near the electrode. In this case, time-resolved and spatially resolved Raman spectroscopy detection can provide important feedback to reveal the generation, diffusion and disappearance of reaction intermediates.

[0005] The double layer effect causes the local electric field near the electrode to change, thereby affecting the adsorption behavior of the reactants on the electrode surface and the stability of the intermediates. This effect is particularly applicable to organic electrocatalytic reactions such as ethanol oxidation, ethylene glycol oxidation, and benzyl alcohol oxidation. In these reactions, the double layer near the electrode plays a crucial role in the reaction rate, reaction path, and the generation and consumption of intermediates. Through the transient Raman spectroscopy system, the transient processes of these reactions can be captured at the nanosecond level, providing more detailed reaction kinetics information. In addition, the double layer effect gives the electrocatalytic reaction a significant time-space characteristic. The dynamic behavior of the reaction intermediates in the electrode surface area can be detected at a high time resolution, which can accurately reveal the local changes and reaction mechanism of the reaction.

[0006] In the field of electrochemistry, researchers often use a three-electrode system (including a working electrode, a reference electrode, and a counter electrode) to study electrocatalytic reactions on the electrode surface. However, electrocatalytic reactions occur at the interface between the electrode and the electrolyte, and the reaction intermediates in this process are often in a high-energy and short-lived state, making them extremely difficult to detect directly. Although an electrochemical workstation can provide real-time current-voltage (IV) curves to analyze electrochemical reactions occurring on the electrode surface, it cannot directly provide structural information about the reaction intermediates. Therefore, combining spectral analysis techniques with electrochemical systems is key to understanding the mechanisms of these complex electrochemical reactions. Raman spectroscopy, due to its sensitivity to the molecular structure of substances, can provide information about molecular vibration modes and is suitable as a tool for detecting intermediates in electrocatalytic reactions. However, there are several challenges in performing Raman detection in electrochemical systems. First, electrochemical reactions are often dynamic, and the intermediates in the reaction process have transient characteristics, which are difficult to detect with static Raman spectroscopy. Second, the generation, diffusion, and disappearance of reaction intermediates on the electrode surface is a very short process, requiring detection methods with high time resolution. The time resolution of traditional Raman spectroscopy is usually at the millisecond level, which is far lower than the time resolution required for electrocatalytic reactions.

[0007] Transient Raman spectroscopy is a technology that combines time-resolved measurement with Raman spectroscopy. Its basic principle is to excite the sample with a short pulse laser and collect Raman spectral signals at different time delays to detect transient processes in the sample. Summary of the invention

[0008] The present invention provides an electrode surface electrocatalytic process detection system based on transient Raman spectroscopy. By adopting the "pump-probe" principle in transient spectroscopy, it is used to detect the Raman spectra of reaction intermediates generated at different times after electrical excitation, thereby revealing the electrocatalytic reaction mechanism near the electrode under diffusion-driven conditions.

[0009] The technical solution adopted by the present invention is that it includes a circuit part and a transient Raman spectrum test part, wherein the CH2 output port c of the signal generator in the circuit part is electrically connected to the socket d of the electrochemical workstation, the computer is connected to the USB interface e of the electrochemical workstation through a USB to square port data cable, the red clamp h of the electrochemical workstation is connected to the working electrode o in the in-situ Raman cell, the white clamp g is connected to the reference electrode n, and a resistor is connected in series between the green clamp f and the counter electrode m in the in-situ Raman cell, and the two ends of the resistor are respectively connected to the terminal k and the terminal l of the digital oscilloscope; In the transient Raman spectroscopy test part, the pulse delayer is electrically connected to the signal generator, and the pulse delayer is electrically connected to the 532nm nanosecond laser. The nanosecond pulse laser emitted by the 532nm nanosecond laser is reflected by silver mirror one and silver mirror two, and then passes through a 515nm narrow-band filter and Raman filter one. It is focused by the objective lens and irradiated to the spatial area where the reaction intermediate to be tested is located on the electrode surface in the in-situ Raman cell. The light scattered by the reaction intermediate is collected by the objective lens, reflected by Raman filter one and silver mirror three, and filtered by Raman filter two. The light beam is converged by a double-cemented lens onto a charge-coupled device CCD, and finally the Raman spectral signal of the reaction intermediate is obtained.

[0010] The CH2 output port c of the signal generator of the present invention outputs a square wave electrical signal with a high level of 5V and a low level of 0.8V.

[0011] The socket d of the electrochemical workstation of the present invention is a 25-pin socket for controlling the electrolytic cell, and the external trigger signal generated by the signal generator is transmitted to the electrochemical workstation through the 13th signal line of the 25-pin socket and the 7th ground line of the 25-pin socket.

[0012] The resistance of the resistor of the present invention is 100Ω.

[0013] The objective lens of the present invention adopts a 50× high-resolution objective lens.

[0014] In the present invention, the angle of the optical path from the 515nm narrow-band filter to the Raman filter and then to the objective lens is within 6 degrees.

[0015] The 515nm narrow-band filter of the present invention filters nanosecond pulse laser light, allowing only light within a specific wavelength range to pass through while blocking light of other wavelengths.

[0016] The Raman filter of the present invention can block the excitation light and only allow the Raman scattering signal with a longer wavelength to pass through, and the Raman filter is a small-angle reflector.

[0017] After the electric pulse signal ends, the system current decays. At time t, the Raman spectrum signal is detected.

[0018] The present invention adopts a 7.5 cm double cemented lens.

[0019] The beneficial effect of the present invention is that the system used detects the reaction intermediates on the electrode surface and its vicinity with high time resolution and high spatial resolution through transient Raman spectroscopy technology combined with electrical excitation and time-resolved measurement methods during electrochemical reactions. Through this innovative "pump-probe" measurement method, the Raman spectral signals of the reaction intermediates on the electrode surface can be detected on a nanosecond time scale, thereby providing a new way to understand the mechanism of electrocatalytic reactions. The present invention is particularly suitable for electrochemical reaction systems that form a double electrical layer during the reaction process, and can effectively capture the influence of these double electrical layer effects on the dynamic behavior of the reaction intermediates, thereby providing more accurate data support for understanding the local dynamics and reaction mechanism of electrocatalytic reactions.

[0020] In the present invention, the electrochemical workstation generates an electric pulse through a signal generator, which is applied to the electrode as a "pump" signal to trigger the electrochemical reaction. At the same time, a nanosecond pulsed laser is used as a "probe" signal to scan the electrode surface and its vicinity to detect the reaction intermediates generated in the electrode reaction. In this process, by precisely controlling the time delay between the laser pulse and the electric pulse, the Raman spectrum of the reaction intermediates in a certain area of ​​the electrode surface at different times can be obtained. By analyzing these time-resolved Raman spectral signals, researchers can understand the dynamic process of the generation, diffusion and disappearance of the reaction intermediates.

[0021] In addition to time-resolved detection, the present invention also detects reaction intermediates in different spatial regions of the electrode surface by adjusting the focal position of the objective lens. This technology can provide three-dimensional spatial concentration distribution information on the electrode surface and its vicinity, providing an important basis for understanding the spatial heterogeneity of electrocatalytic reactions. By combining time-resolved and space-resolved detection methods, researchers can not only detect the generation time of reaction intermediates, but also understand their diffusion behavior in space. This combination provides a new perspective for revealing local dynamics in complex electrochemical reactions.

[0022] The present invention has excellent adjustability and ease of use. It uses nanosecond laser pulses to detect the Raman spectral signals of reaction intermediates generated during the electrochemical reaction under the action of electric pulses. Through this system, the dynamic process of the electrocatalytic reaction can be accurately monitored and analyzed, providing a powerful tool for studying the mechanism of electrochemical reactions.

[0023] The present invention can flexibly control the process of electrochemical reaction through the high adjustability of the signal generator. In addition, after applying a single electric pulse signal in the electrochemical system, the diffusion of the reaction intermediates can be detected by nanosecond laser pulses at different times and spatial positions, thereby inferring the reaction mechanism and reaction path. The present invention successfully realizes the innovative combination of electrochemistry and physical optics, and provides an efficient means for in-depth research on electrocatalytic reactions. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a system principle diagram of the present invention. DETAILED DESCRIPTION

[0025] The present invention comprises a circuit part and a transient Raman spectrum test part, wherein a CH2 output port c of a signal generator 1 in the circuit part is electrically connected to a socket d of an electrochemical workstation 2, a computer 3 is connected to a USB interface e of the electrochemical workstation 2 via a USB to square port data cable, a red clamp h of the electrochemical workstation 2 is connected to a working electrode o in an in-situ Raman cell 7, a white clamp g is connected to a reference electrode n, a resistor 6 is connected in series between a green clamp f and a counter electrode m in the in-situ Raman cell, and two ends of the resistor 6 are respectively connected to a terminal k and a terminal l of a digital oscilloscope 5; In the transient Raman spectrum test part, the pulse delayer 4 is electrically connected to the signal generator 1, and the pulse delayer 4 is electrically connected to the 532nm nanosecond laser 11. The nanosecond pulse laser emitted by the 532nm nanosecond laser 11 is reflected by the silver mirror 12 and the silver mirror 2 13, and then passes through the 515nm narrow-band filter 14 and the Raman filter 1 15. After being focused by the objective lens 8, it is irradiated to the spatial area where the reaction intermediate to be tested is located on the electrode surface in the in-situ Raman cell 7. The light scattered by the reaction intermediate is collected by the objective lens 8, reflected by the Raman filter 1 15 and the silver mirror 3 16, and then filtered by the Raman filter 2 17. The light beam is converged on the charge-coupled device CCD10 through the double-cemented lens 9, and finally the Raman spectrum signal of the reaction intermediate is obtained.

[0026] The CH2 output port c of the signal generator 1 of the present invention outputs a square wave electrical signal with a high level of 5V and a low level of 0.8V.

[0027] The socket d of the electrochemical workstation 2 of the present invention is a 25-pin socket for controlling the electrolytic cell, and the external trigger signal generated by the signal generator 1 is transmitted to the electrochemical workstation 2 via the 13th signal line and the 7th ground line of the 25-pin socket.

[0028] The resistance of the resistor 6 of the present invention is 100Ω.

[0029] The objective lens 8 of the present invention adopts a 50× high-resolution objective lens.

[0030] In the present invention, the angle of the optical path from the 515 nm narrowband filter 14 to the Raman filter 15 and then to the objective lens 8 is within 6 degrees.

[0031] The 515 nm narrow-band filter 14 of the present invention filters the nanosecond pulse laser, allowing only light within a specific wavelength range to pass through, while blocking light of other wavelengths.

[0032] The Raman filter 15 of the present invention can block the excitation light and only allow the Raman scattering signal with a longer wavelength to pass through, and the Raman filter is a small-angle reflector.

[0033] After the electric pulse signal ends, the system current decays. At time t, the Raman spectrum signal is detected.

[0034] The present invention adopts a double cemented lens 18 of 7.5 cm.

[0035] Combine the following Figure 1 The present invention is further illustrated by experimental examples.

[0036] Circuit part: The CH2 output port c of the signal generator 1 outputs a square wave electrical signal with a high level of 5V and a low level of 0.8V. The signal is transmitted to the electrochemical workstation 2 through the BNC male to 25-core connection cable connected to the "electrolytic cell control" socket d of the electrochemical workstation 2 to trigger its operation. Among them, the high level 5V is the normal state, and the low level 0.8V is the trigger state. The external trigger signal generated by the signal generator 1 is transmitted to the electrochemical workstation 2 through the 13th pin signal line and the 7th pin ground line of the 25-core socket. After the trigger signal reaches the electrochemical workstation, under the control of the computer 3, the electrochemical workstation 2 outputs the required pulse voltage signal. Among them, the computer 3 is connected to the USB interface e of the electrochemical workstation 2 through the USB to square port data cable to ensure the precise control of the pulse voltage. The red chuck h of the electrochemical workstation 2 is connected to the working electrode o in the in-situ Raman cell 7, and the white chuck g is connected to the reference electrode n. In order to measure the transient current changes during the electrochemical reaction, a 100Ω small resistor 6 is connected in series between the green chuck f and the counter electrode m in the in-situ Raman cell. The voltage changes across the small resistor are monitored in real time by a digital oscilloscope 5 to record the transient current response under the action of the pulse voltage. After applying a single electric pulse signal, the current in the electrochemical reaction system will gradually decay with the diffusion of the reaction intermediates. During the current decay process, a specific time Δt is selected to detect the Raman spectrum signal of the reaction intermediates to obtain key information in the electrochemical reaction process.

[0037] Transient Raman spectroscopy test section: The detection of Raman spectroscopy signals is achieved through a pulse delayer (DG535) 4, which is used to accurately adjust the relative delay between the 532nm nanosecond laser 11 and the signal generator, so that the emission of the nanosecond pulse laser is synchronized with the time of the electrochemical reaction. The nanosecond pulse laser emitted by the 532nm nanosecond laser 11 is reflected by the silver mirror 12 and the silver mirror 2 13, and then passes through the 515nm narrow-band filter 14 and the Raman filter 1 15. After the laser is focused by the objective lens 8, it is irradiated to the spatial area on the electrode surface where the reaction intermediate to be tested is located. To ensure effective alignment of the laser and signal collection in the system, the optical path angle from the narrow-band filter 14 to the Raman filter 15 and then to the objective lens 8 must be controlled within 6 degrees. The light scattered by the reaction intermediate is collected by the objective lens 8, reflected by the Raman filter 15 and the silver mirror 3 16, and filtered by the Raman filter 2 17. The light beam is then converged onto the charge coupled device (CCD) 10 through a 7.5 cm double-cemented lens 9, and finally the Raman spectrum signal of the reaction intermediate is obtained.

[0038] The working principle of the present invention is as follows: after the pulse voltage is applied to the electrode, an electrochemical reaction occurs in the electrochemical cell, and the generated reaction intermediates diffuse in the electrolyte. This diffusion process is dominated by the molecular diffusion motion, and the time scale is relatively slow. Therefore, the Raman spectral signals of the reaction intermediates can be detected by using nanosecond laser pulses at different delay times. Through time-resolved detection, key information of the reactants is obtained. At the same time, the concentration changes of the reaction intermediates can be inferred by using the changes in the intensity of the Raman spectral signals detected at different times, thereby further inferring the mechanism and path of the electrocatalytic reaction on the electrode surface. In addition, by changing the focus of the objective lens, the Raman spectral signals of the reaction intermediates at different spatial positions near the electrode can be detected, thereby obtaining the three-dimensional spatial concentration distribution information of the reaction intermediates or products, and the obtained Raman spectral signals are analyzed as follows: (1) Raman spectroscopy signal analysis: Through time-resolved Raman spectroscopy testing, researchers can capture the changes in the Raman signal intensity of the reaction intermediates at different time points. The intensity of these Raman signals is proportional to the concentration of the reaction intermediates. Therefore, by comparing the Raman signal intensity at different time points, the concentration changes and diffusion behavior of the reaction intermediates in the electrocatalytic reaction can be inferred.

[0039] Relationship between signal intensity and concentration: The intensity of Raman spectra is usually closely related to the number of molecules, their molecular structure and their scattering efficiency. During the electrochemical reaction, the concentration change of the reaction intermediates will directly affect the intensity of their scattered light. Researchers can quantitatively analyze the concentration changes of the reaction intermediates by comparing the Raman signal intensity of the reaction intermediates at a specific time point with the Raman signal of a standard substance of known concentration. This analysis method usually includes integrating the peak area or peak intensity of the Raman peak to obtain quantitative data on concentration changes.

[0040] Raman spectral intensity I (v) and reactant concentration C The relationship between can usually be expressed as:

[0041] in, k is a constant, σ ( ν ) is the Raman scattering cross section at a specific wave number ν, and C is the concentration of the reactant. Therefore, the Raman signal intensity is linearly related to the concentration, and the concentration change of the reaction intermediate can be calculated by integrating the Raman signal intensity at different time points.

[0042] (2) Analysis of time-resolved data: Time-resolved Raman spectroscopy provides information about the time-varying concentration of reaction intermediates. At different time points after the start of the electrochemical reaction, the concentration of reaction intermediates will change as the reaction progresses. By recording Raman spectral data at different times and calculating the changes in signal intensity at each time, a curve of the change in concentration of reaction intermediates over time can be established. For example, in the early stages of an electrocatalytic reaction, reaction intermediates may be generated rapidly and reach a peak concentration, and then as the reaction proceeds, the concentration gradually decreases until the reaction is completed.

[0043] The change of reaction intermediate concentration over time can be described using a simple reaction kinetic model. For first-order reaction kinetics, the change of concentration C(t) over time t can be expressed as:

[0044] Among them, C0 is the initial concentration, k is the reaction rate constant, and t is time. By fitting the experimental data to this model, the reaction rate constant k can be obtained, and the mechanism of the reaction can be further inferred.

[0045] (3) Kinetic analysis: By observing the trend of the concentration of reaction intermediates over time, researchers can further infer the kinetic behavior of the reaction. For example, if the concentration of the intermediate decays or increases exponentially over time, it indicates that its generation or consumption process conforms to a specific reaction kinetic model. Common kinetic models include first-order reaction kinetics, second-order reaction kinetics, etc. By fitting experimental data to these models, researchers can draw preliminary conclusions about the reaction rate constant and the reaction mechanism.

[0046] Inference of diffusion behavior: In addition to analyzing concentration changes, the spatial distribution of Raman spectroscopy signals can also provide information on the diffusion of reaction intermediates on and near the electrode surface. In electrochemical reactions, reaction intermediates undergo a diffusion process around the electrode surface, which results in a spatially inhomogeneous distribution of intermediate concentrations. By collecting Raman spectra of reaction intermediates at different locations (different focal points), researchers can further analyze the diffusion coefficients of reaction intermediates and their concentration gradients in different electrode regions. This spatial resolution capability can help researchers reveal the heterogeneity of electrode surfaces and the local kinetic characteristics of electrocatalytic reactions.

[0047] The diffusion process usually conforms to Fick's diffusion law. The distribution of the concentration C(x, t) of the reaction intermediate in space and time can be expressed as:

[0048] Where D is the diffusion coefficient, x is the spatial coordinate, and t is time. By measuring the concentration changes at different locations and combining them with the Raman spectroscopy signal intensity, researchers can infer the diffusion coefficient D and the diffusion behavior of the reaction intermediates on the electrode surface.

[0049] Inference of reaction paths and mechanisms: Changes in the concentration of reaction intermediates can also help researchers understand the reaction paths and mechanisms of electrocatalytic reactions. For example, by comparing the concentration changes of reaction intermediates under different reaction conditions, researchers can determine how the reaction intermediates are generated and consumed, and whether there are multiple intermediate conversion steps. In addition, changes in the concentration curve can also reveal key characteristics such as the reversibility of the reaction and the stability of the catalyst.

[0050] Data processing and fitting: In the process of processing Raman spectroscopy data, it is often necessary to remove the background, suppress noise and correct the baseline of the signal. On this basis, the peak area or peak intensity changes are further analyzed by peak fitting and integral calculation of the signal to obtain the quantitative changes in the concentration of the intermediates. Commonly used data processing methods include Lorentzian or Gaussian function fitting, which helps to improve the analysis accuracy of Raman signals, especially when multiple reaction intermediates coexist.

[0051] Summary: The present invention adopts the "pump-probe" principle based on transient spectroscopy, and applies a step potential as a "pump" signal to the electrode at a specific time point t=0 to trigger the electrochemical reaction. At the same time, nanosecond laser pulses are used as detection light, and the Raman spectral signal of the reaction intermediate at a certain spatial position on the electrode surface at the delay time t=△t is recorded by a charge-coupled device (CCD), thereby confirming the key information of the electrocatalytic reactant. In addition, the system also monitors the current-time (I–t) curve of the entire electrochemical reaction system through a digital oscilloscope. The electrochemical reaction system adopts a three-electrode configuration, including a counter electrode, a working electrode, and a reference electrode, to ensure precise control of the electrochemical reaction.

[0052] By analyzing the changes in Raman spectral signal intensity over time and the concentration distribution in different spatial regions, researchers can obtain detailed dynamic behavior information of electrocatalytic reaction intermediates. This information not only helps to reveal the time dependence of the reaction, but also reflects the diffusion behavior of the reaction intermediates, the reaction kinetics, and the heterogeneity of the electrode surface. Using these data, researchers can further speculate on the mechanism and path of the electrochemical reaction, providing a theoretical basis for optimizing electrocatalytic reactions and improving catalytic efficiency.

Claims

1. A system for detecting the electrocatalytic process on the electrode surface based on transient Raman spectroscopy, characterized in that: It includes a circuit part and a transient Raman spectrum test part, wherein the CH2 output port c of the signal generator in the circuit part is electrically connected to the socket d of the electrochemical workstation, the computer is connected to the USB interface e of the electrochemical workstation through a USB to square port data cable, the red clamp h of the electrochemical workstation is connected to the working electrode o in the in-situ Raman cell, the white clamp g is connected to the reference electrode n, a resistor is connected in series between the green clamp f and the counter electrode m in the in-situ Raman cell, and both ends of the resistor are respectively connected to the terminal k and the terminal l of the digital oscilloscope; In the transient Raman spectroscopy test part, the pulse delayer is electrically connected to the signal generator, and the pulse delayer is electrically connected to the 532nm nanosecond laser. The nanosecond pulse laser emitted by the 532nm nanosecond laser is reflected by silver mirror one and silver mirror two, and then passes through a 515nm narrow-band filter and Raman filter one. It is focused by the objective lens and irradiated to the spatial area where the reaction intermediate to be tested is located on the electrode surface in the in-situ Raman cell. The light scattered by the reaction intermediate is collected by the objective lens, reflected by Raman filter one and silver mirror three, and filtered by Raman filter two. The light beam is converged by a double-cemented lens onto a charge-coupled device CCD, and finally the Raman spectral signal of the reaction intermediate is obtained.

2. The electrode surface electrocatalytic process detection system based on transient Raman spectroscopy according to claim 1, characterized in that: The CH2 output port c of the signal generator outputs a square wave electrical signal with a high level of 5V and a low level of 0.8V.

3. The electrode surface electrocatalytic process detection system based on transient Raman spectroscopy according to claim 1, characterized in that: The socket d of the electrochemical workstation is a 25-pin socket for controlling the electrolytic cell, and the external trigger signal generated by the signal generator is transmitted to the electrochemical workstation through the 13th signal line and the 7th ground line of the 25-pin socket.

4. The electrode surface electrocatalytic process detection system based on transient Raman spectroscopy according to claim 1, characterized in that: The resistance of the resistor is 100Ω.

5. The electrode surface electrocatalytic process detection system based on transient Raman spectroscopy according to claim 1, characterized in that: The objective lens adopts a 50× high-resolution objective lens.

6. The electrode surface electrocatalytic process detection system based on transient Raman spectroscopy according to claim 1, characterized in that: The angle of the optical path from the 515nm narrowband filter to the Raman filter and then to the objective lens is within 6 degrees.

7. The electrode surface electrocatalytic process detection system based on transient Raman spectroscopy according to claim 1, characterized in that: The 515nm narrow-band filter filters the nanosecond pulse laser, allowing only light within a specific wavelength range to pass through while blocking light of other wavelengths.

8. The electrode surface electrocatalytic process detection system based on transient Raman spectroscopy according to claim 1, characterized in that: The Raman filter can block the excitation light and only allow the Raman scattering signal with a longer wavelength to pass through, and the Raman filter is a small-angle reflector.

9. The electrode surface electrocatalytic process detection system based on transient Raman spectroscopy according to claim 1, characterized in that: After the electric pulse signal ends, the system current decays At time t, the Raman spectrum signal is detected.

10. The electrode surface electrocatalytic process detection system based on transient Raman spectroscopy according to claim 1, characterized in that: A 7.5 cm doublet lens is used.

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