Pulse broadening transient Raman detection system for researching electrode electro-catalysis process

Abstract

The invention relates to a pulse broadening transient Raman detection system for researching an electrode electro-catalysis process, and belongs to the technical field of Raman spectrum. Comprising a resistor, a digital oscilloscope, a computer, an electrochemical workstation, a signal generator, a femtosecond laser, a first silver mirror, a second silver mirror, a crystal, a dichroscope, a pulse stretcher, a diaphragm, a narrow-band optical filter, a sixth silver mirror, a first Raman optical filter, a reflection diaphragm, an objective lens, a pulse delayer, a seventh silver mirror, a second Raman optical filter, a doublet lens, an electrolytic tank and a charge-coupled device. The device has the advantages that high-time-resolution and high-spatial-resolution detection is carried out on reaction intermediates on the surface of the electrode and in the vicinity of the electrode through a transient Raman spectrum technology carrying a pulse broadening device and in combination with an electric excitation and time-resolution measurement method in an electrochemical reaction process; raman signals of reaction intermediates on the surface of the electrode can be detected on the femtosecond-level time scale, so that a new way is provided for understanding an electro-catalytic reaction mechanism.

Description

Technical Field

[0001] The present invention belongs to the technical field of Raman spectroscopy, and particularly relates to a pulse broadening transient Raman detection system for studying the electrocatalytic process of electrodes. Background Art

[0002] Electrocatalytic reactions play a crucial role in many fields, especially in energy conversion, storage, and environmental protection, such as fuel cells, water electrolysis for hydrogen production, 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 processes of electrochemically reactive intermediates occurring on the electrode surface. These processes are often accompanied by rapid mass and energy exchange, especially the evolution of reactive intermediates occurring on a short time scale, which directly affects the electrocatalytic performance and reaction efficiency. Therefore, accurately detecting the behaviors of these reactive intermediates has become the key to understanding the electrocatalytic reaction mechanism.

[0003] In the prior art, Raman spectroscopy, as a non-contact and non-destructive analysis tool, has been widely used in materials science and electrochemistry reaction research. Raman spectroscopy can provide important information about the chemical composition, molecular structure, and bonding state of the research object by detecting molecular vibration modes. However, traditional Raman spectroscopy technology has problems of insufficient spatial resolution and time resolution, making it difficult to effectively observe the reaction process within a short time. Especially in electrocatalytic reactions, the generation and disappearance of reactive intermediates are transient and often occur on a nanosecond or shorter time scale. To better detect the dynamic behaviors in these electrocatalytic processes, it is necessary to combine time-resolved Raman spectroscopy technology with electrochemical means to capture the generation and evolution processes of reactive intermediates at a higher time resolution. In addition, the complexity of the electrode surface during the electrochemical reaction also makes it necessary to resolve and detect the reactive 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 analysis means but also high-precision measurement of three-dimensional spatial information on the electrode surface and its vicinity. This need has prompted researchers to develop detection systems that can simultaneously achieve high time resolution and high spatial resolution.

[0004] 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 the electrocatalytic reactions on the electrode surface. However, the electrocatalytic reaction occurs at the electrode / electrolyte interface, and the reaction intermediates in this process are often in a high-energy and short-lived state, making them extremely difficult to be directly detected. Although an electrochemical workstation can provide real-time current-voltage (I-V) curves for analyzing the electrochemical reactions occurring on the electrode surface, it cannot directly provide the structural information of the reaction intermediates. Therefore, combining spectroscopic analysis techniques with an electrochemical system is necessary to understand the mechanisms of these complex electrochemical reactions. Although Raman spectroscopy, due to its sensitivity to the molecular structure of substances, can provide information on molecular vibration modes and is suitable as a tool for detecting electrocatalytic reaction intermediates, there are several challenges in performing Raman detection in an electrochemical system. First, electrochemistry reactions are often dynamic, and the intermediates during the reaction process have transient characteristics and are difficult to be detected by static Raman spectroscopy. Second, the generation, diffusion, and disappearance of reaction intermediates on the electrode surface are processes with a very short time scale, requiring detection means with high time resolution. The time resolution of traditional Raman spectroscopy is usually in the millisecond level, far lower than the time resolution required for electrocatalytic reactions. Summary of the Invention

[0005] The present invention provides a pulsed broadening transient Raman detection system for studying the electrocatalytic process of an electrode to solve the problems faced in performing Raman detection in an electrochemical system currently, that is, the intermediates during the reaction process have transient characteristics and are difficult to be detected by static Raman spectroscopy, and the time resolution of traditional Raman spectroscopy is usually in the millisecond level, far lower than the time resolution required for electrocatalytic reactions.

[0006] The technical solution adopted by the present invention includes a circuit part, a transient Raman spectroscopy test part, an electrolytic cell, and a charge-coupled device. The circuit part includes a resistor, a digital oscilloscope, a computer, an electrochemical workstation, and a signal generator. The signal generator is electrically connected to the electrochemical workstation. The computer is connected to the USB interface of the electrochemical workstation through a USB to square port data cable. A resistor is connected in series between the electrochemical workstation and the electrolytic cell, and a digital oscilloscope is connected in parallel across both ends of the resistor. The transient Raman spectroscopy test part includes a femtosecond laser, a first silver mirror, a second silver mirror, a BBO crystal, a dichroic mirror, a pulse stretcher, a diaphragm, a narrowband filter, a sixth silver mirror, a first Raman filter, a reflection to the diaphragm, an objective lens, a pulse delay device, a seventh silver mirror, a second Raman filter, and a doublet lens. The pulse delay device is electrically connected to the femtosecond laser. The femtosecond pulsed laser emitted by the femtosecond laser passes through the reflections of the first silver mirror and the second silver mirror, and then passes through the BBO crystal to become green light of 515 nm. This green light passes through the dichroic mirror and is split into a first light and a second light by the pulse stretcher and enters the diaphragm, then passes through the narrowband filter, and is reflected by the sixth silver mirror and the first Raman filter and enters the diaphragm again. The objective lens focuses the light beam into the electrolytic cell and irradiates the spatial region where the reaction intermediate to be measured is located on the electrode surface. The light scattered by the reaction intermediate passes through the objective lens, the diaphragm, and the first Raman filter and reaches the seventh silver mirror. The light beam is reflected by the seventh silver mirror and passes through the second Raman filter and the doublet lens and is focused on the charge-coupled device to obtain the Raman spectral signal of the reaction intermediate.

[0007] The pulse stretcher A includes a third silver mirror, a fourth silver mirror, a fifth silver mirror, and a beam splitter. 50% of the laser reflected by the third silver mirror is directly reflected by the beam splitter into the diaphragm and is called the first light. The other 50% of the laser reflected by the third silver mirror passes through the beam splitter, is reflected again by the fourth silver mirror and the fifth silver mirror and reaches the beam splitter, and is incident into the diaphragm and is called the second light.

[0008] The signal generator outputs a square wave electrical signal with a high level of 5 V and a low level of 0.8 V.

[0009] The high level of 5 V output by the signal generator is the normal state, and the low level of 0.8 V is the trigger state.

[0010] The resistance of the resistor is 100 Ω.

[0011] The signal generator is electrically connected to the pulse delay device.

[0012] The narrowband filter is used to filter out unnecessary light and only allows light within a specific wavelength range to pass through to ensure the purity and accuracy of the Raman signal.

[0013] During the current decay stage after the electrical pulse signal ends, the pulse delay device is used to precisely control the time Δ𝑡, and the Raman signal of the reaction intermediate is detected by the femtosecond laser pulse.

[0014] The Raman filter 1 and Raman filter 2 are used to block the excitation light and only allow the Raman scattering signals with longer wavelengths to pass through.

[0015] A resistor is connected in series between the green chuck d of the electrochemical workstation and the counter electrode c in the electrolytic cell, the red chuck f is connected to the working electrode a in the electrolytic cell, and the white chuck e is connected to the reference electrode b.

[0016] The beneficial effects of the present invention are as follows: Through the transient Raman spectroscopy technology equipped with a pulse broadening device, combined with the electrical excitation and time-resolved measurement methods in the electrochemical reaction process, the present invention can detect the reaction intermediates on the electrode surface and in the nearby areas with high time resolution and high spatial resolution. Through this innovative multi-pulse "pump-probe" measurement method, the Raman signals of the reaction intermediates on the electrode surface can be detected on the femtosecond time scale, thus providing a new way to understand the electrocatalytic reaction mechanism.

[0017] The present invention has excellent adjustability and ease of use. By using an open transient Raman system with pulse broadening to detect the Raman signals of the reaction intermediates generated during the electrochemical reaction under the action of electrical pulses, the dynamic process of the electrocatalytic reaction can be accurately monitored and analyzed, providing a powerful tool for studying the electrochemistry reaction mechanism. The high adjustability of the signal generator of the present invention can flexibly control the process of the electrochemical reaction. After applying a single electrical pulse signal in the electrochemical system, the diffusion of the reaction intermediates can be detected by femtosecond laser pulses at different times and spatial positions.

[0018] The present invention realizes the efficient detection of the reaction intermediates during the electrocatalytic reaction process. By introducing femtosecond laser pulses, the transient process in the electrocatalytic reaction can be detected with femtosecond time resolution, achieving high time resolution and overcoming the deficiency that traditional Raman spectroscopy cannot capture fast reaction intermediates. In addition, a pulse stretcher is introduced: by broadening the short-pulse laser, the capture probability of the Raman signal is increased, and the peak power is also reduced during this process, avoiding damage to the optical components. By adjusting the focal position of the objective lens, accurate three-dimensional spatial detection of the electrode surface and its nearby areas can be achieved, realizing high spatial resolution and better revealing the spatial distribution of the reaction intermediates.

[0019] The present invention organically combines the electrochemical workstation and the Raman spectroscopy system, realizing the all-round monitoring of the generation, diffusion, and disappearance of substances in the electrochemical reaction, providing a powerful tool for the study of the electrocatalytic reaction, providing more complete information on the electrocatalytic reaction process, and is expected to promote the further development of this field. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is the system schematic diagram of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0021] See Figure 1 It includes a circuit part, a transient Raman spectroscopy test part, an electrolytic cell 16 and a charge-coupled device CCD20. The circuit part includes a resistor 17, a digital oscilloscope 18, a computer 19, an electrochemical workstation 21, and a signal generator 22. The signal generator 22 is electrically connected to the electrochemical workstation 21. The computer 19 is connected to the USB interface of the electrochemical workstation 21 through a USB to square port data cable to ensure precise control of the pulsed voltage. After the trigger signal arrives at the electrochemical workstation 21, under the control of the computer 19, the electrochemical workstation 21 outputs the required pulsed voltage signal. To measure the transient current change during the electrochemical reaction process, a 100Ω resistor 17 is connected in series between the green clamp d of the electrochemical workstation 21 and the counter electrode c in the electrolytic cell 16, the red clamp f is connected to the working electrode a in the electrolytic cell 16, and the white clamp e is connected to the reference electrode b. The digital oscilloscope 18 is connected in parallel across the resistor 17. The voltage change across the resistor 17 is monitored in real time by the digital oscilloscope 18 to record the transient current response under the action of the pulsed voltage. After applying a single electrical pulse signal, the current in the electrochemical reaction system gradually decays as the reaction intermediate diffuses. During the current decay process, a specific time Δ𝑡 is selected to detect the Raman signal of the reaction intermediate to obtain key information during the electrochemical reaction process.

[0022] The transient Raman spectroscopy test part includes a femtosecond laser 1, a first silver mirror 2, a second silver mirror 3, a BBO crystal 4, a dichroic mirror 5, a pulse stretcher A, a diaphragm 9, a narrowband filter 11, a sixth silver mirror 12, a first Raman filter 13, a reflected diaphragm 14, an objective lens 15, a pulse delay device 23, a seventh silver mirror 24, a second Raman filter 25, and a doublet lens 26. The pulse delay device 23 is electrically connected to the femtosecond laser 1. The detection of the Raman signal is achieved through the pulse delay device DG535 (23), which is used to precisely adjust the relative delay between the femtosecond laser 1 and the signal generator 22 to synchronize the emission of the femtosecond pulsed laser with the time of the electrochemical reaction. The femtosecond pulsed laser emitted by the femtosecond laser 1 is reflected by the first silver mirror 2 and the second silver mirror 3, and then passes through the BBO crystal 4 to become green light of 515nm. This green light passes through the dichroic mirror 5, is split into light beam 1 and light beam 2 by the pulse stretcher and enters the diaphragm 9, then passes through the narrowband filter 11, the sixth silver mirror 12, the first Raman filter 13, and is reflected into the diaphragm 14. The objective lens 15 focuses the light beam into the electrolytic cell 16 and irradiates the spatial region on the electrode surface where the reaction intermediate to be measured is located. The light scattered by the reaction intermediate (dotted line) passes through the objective lens 15, the diaphragm 14, and the Raman filter 13 and reaches the seventh silver mirror 24. The light beam is reflected by the seventh silver mirror 24 and passes through the second Raman filter 25 and the doublet lens 26 to be focused on the charge-coupled device CCD20 to obtain the Raman spectroscopic signal of the reaction intermediate.

[0023] The pulse stretcher A includes a silver mirror three 6, a silver mirror four 7, a silver mirror five 8 and a beam splitter 10. 50% of the laser reflected by the silver mirror three 6 is directly reflected by the beam splitter 10 into the aperture 9 and is called light No. 1. The other 50% of the laser reflected by the silver mirror three 6 passes through the beam splitter 10, is reflected again by the silver mirror four 7 and the silver mirror five 8 and reaches the beam splitter 10, and is incident on the aperture 9 and is called light No. 2. Since the optical paths of the two beams of light are different, the arrival times at the sample surface are different, which results in an additional beam of light in a single pulsed light to detect the Raman signal of the reaction intermediate. During the reaction process of the sample, there are multiple pulsed lights to detect the signal. Therefore, a large number of additional beams of light will be added to detect the signal, which greatly increases the probability of detecting the signal of the reaction intermediate. Since the output optical power of the laser overflows, the influence of the presence of the beam splitter 10 on the light intensity and optical power does not need to be considered here.

[0024] The signal generator 22 outputs a square wave electrical signal with a high level of 5V and a low level of 0.8V. This signal is transmitted through the circuit to the electrochemical workstation 21 to trigger its operation. The high level of 5V output by the signal generator 22 is the normal state, and the low level of 0.8V is the trigger state.

[0025] The resistance of the resistor 17 is 100Ω.

[0026] The signal generator 22 is electrically connected to the pulse delayer 23.

[0027] The narrowband filter 11 is used to filter out unnecessary light and only allows light within a specific wavelength range to pass through to ensure the purity and accuracy of the Raman signal.

[0028] During the current decay stage after the end of the electrical pulse signal, the pulse delayer 23 is used to precisely control the time Δ𝑡, and the Raman signal of the reaction intermediate is detected by the femtosecond laser pulse.

[0029] The Raman filter one 13 and the Raman filter two 25 are used to block the excitation light and only allow the Raman scattering signal with a longer wavelength to pass through.

[0030] System working principle The present invention is used to study the electrocatalytic process on the electrode surface. It adopts the "pump-probe" principle in transient spectroscopy to detect the Raman spectra of reaction intermediates generated at different times after electrical excitation, so as to reveal the electrocatalytic reaction mechanism near the electrode driven by diffusion.

[0031] The present invention is equipped with a pulse stretcher in a transient Raman system. It consists of three silver mirrors and a beam splitter 10. The split light propagates in the delay arm composed of three silver mirrors. Since the number of times passing through the silver mirror 7 is different, the optical path is different. Although the propagation speed is the same in the same medium, the propagation time is different. For example, the split light that does not pass through the silver mirror 7 has the shortest optical path and the shortest light propagation time; the split light that passes through the silver mirror 7 once has a longer optical path and a longer light propagation time. In this way, the light that originally starts from the beam splitter at the same time has a time difference when it reaches the beam splitter again, and naturally there is also a time difference when it reaches the sample. In this way, the isochronous short pulse light emitted by the laser is delay-replicated. Since the number of light beams increases with time, the probability of capturing Raman signals is greatly improved. In short, a pulse stretcher A is installed in the open optical path. The optical paths of the light beams passing through the beam splitter 10 are different, so the arrival times at the sample are different. During the process of detecting Raman signals, a large number of additional light beams are added, greatly improving the capture probability of Raman signals.

[0032] The transient Raman spectroscopy technique with pulse broadening is a technique that combines Raman spectroscopy with time-resolved measurement. Its basic principle is that a short-pulse laser passes through a series of optical elements such as a pulse stretcher composed of a beam splitter and a total reflection mirror, and Raman signals are collected at different time delays, thereby realizing the detection of transient processes in samples. The presence of the pulse stretcher greatly increases the probability of measuring Raman signals of chemical reaction intermediates. And with the accumulation of time differences, the pulse is stretched in the time domain, reducing the peak power and avoiding damage to optical elements. To achieve this process, first, a pulse stretcher composed of three reflectors and a beam splitter needs to be introduced into the open optical path, where the optical path can be adjusted by researchers themselves. For different samples, different optical paths can be adjusted to select different pulse broadenings.

[0033] The present invention introduces a measurement scheme similar to the "pump-probe" technique. The electrochemical workstation generates an electrical pulse through a signal generator and applies it as the "pump" signal to the electrode to trigger an electrochemical reaction. At the same time, a femtosecond pulsed laser serves as the "probe" signal to scan the surface of the electrode and its vicinity to detect the reaction intermediates generated in the electrode reaction. During this process, by precisely controlling the time delay between the laser pulse and the electrical pulse, Raman spectra of reaction intermediates in a certain area on the electrode surface at different times can be obtained. By analyzing these time-resolved Raman signals, researchers can understand the dynamic processes of the generation, diffusion, and disappearance of reaction intermediates.

[0034] Based on the "pump-probe" principle of transient spectroscopy, a step potential is applied at a specific time point t = 0 as the "pump" signal to act on the electrode, triggering an electrochemical reaction. Meanwhile, a femtosecond laser pulse is used as the probe light, and the Raman spectroscopic signal of the reaction intermediate at a certain spatial position on the electrode surface is recorded by a charge-coupled device (CCD) at the delay time t = Δ𝑡, 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.

[0035] A high-low level signal is generated by the signal generator 22 to trigger the electrochemical workstation to output an electrical pulse signal, driving the electrochemical reaction. A small-value resistor of 100Ω is connected in series in the whole circuit, and the current change across the resistor is monitored in real time through a digital oscilloscope, thereby recording the transient current response of the electrochemical reaction system under the action of the electrical pulse signal. After applying a single electrical pulse signal, the reaction in the electrochemical cell proceeds as the intermediate diffuses, and the system current gradually decreases. During this process, the behavior of the reaction intermediate is analyzed by detecting the Raman signal.

[0036] The detection of the Raman signal is achieved by adjusting the relative delay between the femtosecond laser 1 and the signal generator 22 through the pulse delay device 23. The pulsed laser emitted by the femtosecond laser passes through a series of optical elements to reach the objective lens and is focused on the reaction intermediate to be measured. The light scattered by the reaction intermediate passes through the objective lens and the silver mirror and then converges into the CCD, thereby collecting Raman signals at different time points and different spatial positions.

[0037] After the pulsed voltage is applied to the electrode, an electrochemical reaction occurs in the electrochemical workstation 21, and the generated reaction intermediate diffuses in the electrolyte. This diffusion process is dominated by molecular diffusion motion and has a relatively slow time scale. Therefore, the Raman signal of the reaction intermediate can be detected by using femtosecond laser pulses at different delay times. Through time-resolved detection, the key information of the reactant can be obtained. At the same time, by using the change in the Raman signal intensity detected at different times, the concentration change of the reaction intermediate can be inferred, thereby further inferring the mechanism and path of the electrocatalytic reaction on the electrode surface. In addition to time-resolved detection, by changing the focus of the objective lens, the Raman signals of the reaction intermediate at different spatial positions near the electrode can be detected, thereby obtaining the three-dimensional spatial concentration distribution information of the reaction intermediate or product. The present invention realizes the detection of the reaction intermediate on different spatial regions of the electrode surface by adjusting the focus position of the objective lens. This technology can provide the three-dimensional spatial concentration distribution information of the electrode surface and its nearby regions, providing an important basis for understanding the spatial heterogeneity of the electrocatalytic reaction.

[0038] 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 the local dynamics in complex electrochemical reactions.

Claims

1. A pulse broadening transient Raman detection system for studying electrode electrocatalytic processes, characterized in that: The invention comprises a circuit part, a transient Raman spectrum test part, an electrolytic cell and a charge coupled device, wherein the circuit part comprises a resistor, a digital oscilloscope, a computer, an electrochemical workstation and a signal generator, wherein the signal generator is electrically connected to the electrochemical workstation, the computer is connected to the USB interface of the electrochemical workstation through a USB to square port data cable, a resistor is connected in series between the electrochemical workstation and the electrolytic cell, and the digital oscilloscope is connected in parallel at both ends of the resistor; the transient Raman spectrum test part comprises a femtosecond laser, a silver mirror 1, a silver mirror 2, a BBO crystal, a dichroic mirror, a pulse stretcher, an aperture, a narrow band filter, a silver mirror 6, a Raman filter 1, a reflection to the aperture, an objective lens, a pulse delayer, a silver mirror 7, a Raman filter 2 and a double glued The lens comprises a pulse delay device and a femtosecond laser, wherein the pulse delay device is electrically connected to the femtosecond laser, the femtosecond pulse laser emitted by the femtosecond laser is reflected by the silver mirror 1 and the silver mirror 2, and then is converted into a 515nm green light by the BBO crystal, the green light is divided into light No. 1 and light No. 2 by the dichroic mirror and the pulse stretcher to the aperture, and then passes through the narrow band filter, is reflected by the silver mirror 6 and the Raman filter 1 to the aperture, the light beam is converged into the electrolytic cell by the objective lens, and irradiated to the spatial area where the reaction intermediate to be measured is located on the electrode surface, the light scattered by the reaction intermediate passes through the objective lens, the aperture, and the Raman filter 1 to reach the silver mirror 7, the light beam is reflected by the silver mirror 7 and passes through the Raman filter 2 and the double glued lens to be converged on the charge coupled device, and the Raman spectrum signal of the reaction intermediate is obtained.

2. The pulse broadening transient Raman detection system for studying electrode electrocatalytic processes according to claim 1, characterized in that: The pulse stretcher A includes silver mirror three, silver mirror four, silver mirror five and a beam splitter, wherein 50% of the laser light reflected by silver mirror three is directly reflected by the beam splitter into the aperture and is called light No. 1, and the other 50% of the laser light reflected by silver mirror three passes through the beam splitter, is reflected again by silver mirror four and silver mirror five to reach the beam splitter, and is incident into the aperture and is called light No.

2.

3. The pulse broadening transient Raman detection system for studying electrode electrocatalytic processes according to claim 1, characterized in that: The signal generator outputs a square wave electrical signal with a high level of 5V and a low level of 0.8V.

4. The pulse broadening transient Raman detection system for studying electrode electrocatalytic processes according to claim 3, characterized in that: The high level 5V output by the signal generator is a normal state, and the low level 0.8V is a trigger state.

5. The pulse broadening transient Raman detection system for studying electrode electrocatalytic processes according to claim 1, characterized in that: The resistance of the resistor is 100Ω.

6. The pulse broadening transient Raman detection system for studying electrode electrocatalytic processes according to claim 1, characterized in that: The signal generator is electrically connected to the pulse delayer.

7. The pulse broadening transient Raman detection system for studying electrode electrocatalytic processes according to claim 1, characterized in that: The narrowband filter is used to filter out unnecessary light and only allow light within a specific wavelength range to pass through, so as to ensure the purity and accuracy of the Raman signal.

8. The pulse broadening transient Raman detection system for studying electrode electrocatalytic processes according to claim 1, characterized in that: During the current decay phase after the electric pulse signal ends, a pulse delay device is used to precisely control the time Δ𝑡, and a femtosecond laser pulse is used to detect the Raman signal of the reaction intermediate.

9. The pulse broadening transient Raman detection system for studying electrode electrocatalytic processes according to claim 1, characterized in that: The Raman filter 1 and the Raman filter 2 are used to block the excitation light and only allow the Raman scattering signal with a longer wavelength to pass through.

10. The pulse broadening transient Raman detection system for studying electrode electrocatalytic processes according to claim 1, characterized in that: A resistor is connected in series between the green chuck d of the electrochemical workstation and the counter electrode c in the electrolytic cell, the red chuck f is connected to the working electrode a in the electrolytic cell, and the white chuck e is connected to the reference electrode b.

Images