An in-situ Raman testing device suitable for high-voltage flow three-phase interfaces

Abstract

This invention discloses an in-situ Raman testing device suitable for high-pressure flow three-phase interfaces, belonging to the field of spectroscopic instrument accessories and instrumental analysis technology. It includes a gas chamber, a cathode chamber insulating clamp, a cathode chamber, a cover plate, an anode chamber insulating clamp, an anode chamber, and optical glass. This invention features simple assembly, good sealing, and facilitates the acquisition of high-quality Raman spectral information. Furthermore, the device allows the reaction cell to be embedded in the sample stage of a Raman spectrometer, the solution pipeline to be connected to a pressure-controlled balancing device, and to an electrochemical workstation and Raman system, enabling optical signal testing under high-pressure flow three-phase interface conditions. It has proven highly effective in the mechanistic and applied research of electrocatalytic / photoelectrocatalytic reactions using practical gas diffusion electrodes.

Description

Technical Field

[0001] This invention relates to the field of spectroscopic instrument accessories and instrument analysis technology, and more specifically, to an in-situ Raman testing device suitable for high-pressure flow three-phase interfaces. Background Technology

[0002] In-situ Raman spectroscopy, based on the interaction between light and chemical bonds within materials, offers advantages such as simplicity, versatility, and non-destructive nature. Because in-situ Raman spectroscopy can directly obtain fingerprint peaks of reactant species at the molecular level, it can provide detailed information such as sample chemical structure, crystallinity, and molecular interactions, making it an important research tool for characterizing electrode / electrolyte interfacial processes.

[0003] In the testing and research of electrocatalytic reactions using in-situ Raman spectroscopy, it is necessary to use an in-situ Raman electrochemical cell to replicate the reaction conditions as closely as possible while simultaneously meeting the requirements for in-situ Raman spectral signal acquisition. Currently, although some Raman reaction cells are available on the market, both two-phase interface and three-phase interface reaction cells with gas diffusion electrodes are designed for atmospheric pressure. This artificially ignores a large category of high-pressure reaction systems, resulting in a significant gap from actual industrial production. Currently, there are few reports of electrolytic cells that simultaneously meet the requirements of flow cytometry, high pressure, and in-situ Raman testing. Summary of the Invention

[0004] To address the shortcomings of existing technologies, the present invention aims to provide an in-situ Raman testing device suitable for high-pressure flow three-phase interfaces, thereby solving the problem of testing in-situ Raman signals in high-pressure electrolytic cells under different pressures.

[0005] To achieve the above objectives, this invention provides an in-situ Raman testing device suitable for high-pressure flow three-phase interfaces, comprising a gas chamber, a cathode chamber insulating clamp, a cathode chamber, a cover plate, an anode chamber insulating clamp, and an anode chamber. The cathode chamber insulating clamp is located between the gas chamber and the cathode chamber. A gas hole is opened in the center of the gas chamber. A gas diffusion electrode is disposed between the cathode chamber insulating clamp and the cathode chamber, the size of which covers the gas hole. The gas chamber includes an inlet and an outlet. Most of the gas is directly discharged outside the gas chamber through the outlet, while a small portion of the gas enters the gas diffusion electrode through the gas hole to undergo an electrocatalytic reaction. The cathode chamber has an electrode groove for a high-voltage reference electrode and a liquid inlet. The cathode chamber and the cover plate have central openings and are inlaid with optical glass. The anode chamber insulating clamp and the anode chamber, together with the gas chamber, cathode chamber insulating clamp, cathode chamber, and cover plate, are vertically placed as a whole. A counter electrode is disposed between the anode chamber insulating clamp and the anode chamber, and the anode chamber has a liquid outlet. Sealing ring grooves are provided at the contact points of each component, forming a closed, pressure-resistant system through sealing ring fastening.

[0006] During operation, electrolyte is introduced through the inlet, flows in the cathode and anode chambers, and then flows out from the outlet. Gas is introduced into the gas chamber, where an electrocatalytic reaction occurs at the gas diffusion electrode. The changes in the gas diffusion electrode reaction are observed through optical glass, and Raman spectral signals during the electrocatalytic reaction process are collected.

[0007] Furthermore, the air chamber has screw holes for fixing the testing device.

[0008] Furthermore, there is an air inlet in the middle of one side of the air chamber and an air outlet in the middle of the upper side, following the principle of bottom inlet and top outlet, and the pressurization operation of the test device is realized through the back pressure valve.

[0009] Furthermore, the sealing ring groove includes a gas chamber sealing ring groove connecting the gas chamber and the cathode chamber insulating clamp, a first sealing ring groove for the cathode chamber insulating clamp, a second sealing ring groove for the cathode chamber insulating clamp connecting the cathode chamber insulating clamp and the cathode chamber, a first sealing ring groove for the cathode chamber, a second sealing ring groove for the cathode chamber connecting the cathode chamber and the anode chamber insulating clamp, a third sealing ring groove for the cathode chamber connecting the cathode chamber and the cover plate, a fourth sealing ring groove for the cathode chamber connecting the cathode chamber and the optical glass, a first sealing ring groove for the cover plate connecting the cathode chamber and the cover plate, a second sealing ring groove for the cover plate connecting the cover plate and the optical glass, a first sealing ring groove for the anode chamber insulating clamp connecting the cathode chamber and the anode chamber insulating clamp, a second sealing ring groove for the anode chamber insulating clamp connecting the anode chamber insulating clamp and the anode chamber, and an anode chamber sealing ring groove connecting the anode chamber insulating clamp and the anode chamber.

[0010] Furthermore, each of the sealing ring grooves is an O-ring groove.

[0011] Furthermore, the cathode chamber insulating clamp has two sealing ring grooves, which correspond to the gas chamber sealing ring groove and the cathode chamber first sealing ring groove, respectively.

[0012] Furthermore, the cathode chamber includes a liquid inlet located in the lower middle part of one side and a channel in the upper middle part of one side for connecting the reference electrode, the thread of which is M10*1 according to national standard.

[0013] Furthermore, a boss with adjustable height is provided in the cathode chamber cavity. By adjusting the height of the boss, the solution thickness between the optical glass and the working electrode can be changed. The fourth sealing ring groove of the cathode chamber can support the optical glass, allowing it to withstand a certain pressure without breaking. The cavity is the area where the catalytic reaction occurs.

[0014] Furthermore, the first sealing ring groove of the cover plate corresponds to the third sealing ring groove of the cathode chamber, the second sealing ring groove of the cover plate can receive the optical glass, and the height of the cylindrical boss of the cover plate can be adjusted according to the thickness of the optical glass.

[0015] Furthermore, the first sealing ring groove of the anode chamber insulating clamp corresponds to the second sealing ring groove of the cathode chamber, and the cavity of the anode chamber insulating clamp corresponds to the cavity of the cathode chamber, serving as a channel for liquid flow. The second sealing ring groove of the anode chamber insulating clamp corresponds to the sealing ring groove of the anode chamber.

[0016] Furthermore, the anode chamber cavity houses the counter electrode, and the liquid flows in from the cathode chamber and out from the anode chamber, achieving liquid circulation through a high-pressure circulating pump.

[0017] Furthermore, the diameter of the optical glass is slightly larger than the diameter of the cylindrical boss on the cover plate, and the optical glass is made of quartz glass or transparent sapphire.

[0018] Furthermore, the cathode chamber insulating clamp and the anode chamber insulating clamp are made of PTFE material, while the gas chamber, cathode chamber, cover plate and anode chamber are all made of stainless steel or titanium alloy.

[0019] Furthermore, the cathode chamber and the cover plate are fixed with the optical glass by a sealing ring and screws. The optical window is located in the center of the electrolytic cell. The gas chamber, the cathode chamber insulating clamp, the cathode chamber, the optical glass, and the cover plate are fastened together with screws and bolts. The cathode chamber, the anode chamber insulating clamp, and the anode chamber are fastened together with screws and bolts.

[0020] Compared with existing technologies, the high-pressure flow three-phase interface Raman electrochemical cell conceived in this invention meets the practical needs of studying the microscopic mechanism of electrocatalytic reactions at three-phase interfaces under high pressure, filling the gap in high-pressure flow three-phase interface reactors. The appropriate use of stainless steel or titanium alloy materials and sealing ring grooves meets the pressure resistance requirements of the reaction cell. By adding internal grooves and bosses to the cathode chamber, the thickness of the electrolyte can be flexibly adjusted to adapt to the optical characteristics of the Raman spectrometer, obtaining high signal-to-noise ratio Raman signals within different pressure ranges. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the overall structure of the original Raman testing device for a high-voltage flow three-phase interface in this invention.

[0022] Figure 2 This is a schematic diagram showing the positions and connections of the gas chamber, the insulating clamp between the gas chamber and the cathode chamber, the cathode chamber, the optical glass, and the cover plate.

[0023] Figure 3 This is a schematic diagram showing the position and connection relationship of the cathode chamber, the insulating clamp between the cathode chamber and the anode chamber, and the anode chamber.

[0024] Reference numerals: 1: Gas chamber; 2: Cathode chamber insulating clamp; 3: Cathode chamber; 4: Cover plate; 5: Anode chamber insulating clamp; 6: Anode chamber; 7: Optical glass; 1-1: Air inlet; 1-2: Air vent; 1-3: Gas chamber sealing ring groove; 1-4: Air outlet; 2-1: First sealing ring groove of cathode chamber insulating clamp; 2-2: Second sealing ring groove of cathode chamber insulating clamp; 3-1: Liquid inlet; 3-2: High-voltage reference electrode; 3-3: First sealing ring groove of cathode chamber; 3-4: 3-5: Cathode chamber third sealing ring groove; 3-6: Cathode chamber fourth sealing ring groove; 3-7: Cathode chamber cavity; 3-8: Cathode chamber second sealing ring groove; 3-9: Cathode chamber solution flow channel; 4-1: Cover plate first sealing ring groove; 4-2: Cover plate second sealing ring groove; 4-3: Cover plate cylindrical boss; 5-1: Anode chamber insulating clamp plate first sealing ring groove; 5-2: Anode chamber insulating clamp plate second sealing ring groove; 6-1: Anode chamber sealing ring groove; 6-2: Liquid outlet. Detailed Implementation

[0025] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention. Furthermore, the technical features involved in the various embodiments of this invention described below can be combined with each other as long as they do not conflict with each other.

[0026] This invention provides an in-situ Raman testing device suitable for high-voltage flow three-phase interfaces, such as... Figure 1 As shown, the system includes a gas chamber 1, a cathode chamber insulating clamp 2, a cathode chamber 3, a cover plate 4, an anode chamber insulating clamp 5, and an anode chamber 6. The cathode chamber insulating clamp 2 is located between the gas chamber 1 and the cathode chamber 3. A gas hole 1-2 is opened in the center of the gas chamber 1. A gas diffusion electrode is disposed between the cathode chamber insulating clamp and the cathode chamber, and the size of the gas diffusion electrode covers the gas hole 1-2. The gas chamber 1 includes an inlet 1-1 and an outlet 1-4. Most of the gas is directly discharged from the gas chamber 1 through the outlet 1-4, and a small portion of the gas enters the gas diffusion chamber through the gas hole 1-2. An electrocatalytic reaction occurs at the electrode; the cathode chamber 3 is provided with an electrode groove, in which a high-voltage reference electrode is configured, and the cathode chamber 3 has a liquid inlet 3-1; the cathode chamber 3 and the cover plate 4 have a central opening and are inlaid with optical glass 7; the anode chamber insulating clamp 5 and the anode chamber 6 are placed at 90° perpendicularly to the whole consisting of the gas chamber 1, the cathode chamber insulating clamp 2, the cathode chamber 3, and the cover plate 4; a counter electrode is provided between the anode chamber insulating clamp 5 and the anode chamber 6, and the anode chamber 6 has a liquid outlet 6-2; each component contact part is provided with a sealing ring groove, and a closed pressure-resistant system is formed by fastening the sealing ring;

[0027] During operation, electrolyte is introduced through inlet 3-1, flows in cathode chamber 3 and anode chamber 6, and then flows out from outlet 6-2; gas is introduced into gas chamber 1, and an electrocatalytic reaction occurs at the gas diffusion electrode. The changes in the gas diffusion electrode reaction are observed through optical glass 7, and Raman spectral signals during the electrocatalytic reaction process are collected.

[0028] Figure 2 This is a schematic diagram showing the positions and connections of gas chamber 1, insulating clamp 2 between gas chamber 1 and cathode chamber, cathode chamber 3, optical glass 7, and cover plate 4.

[0029] Figure 3 This is a schematic diagram showing the position and connection relationship between the cathode chamber 3, the insulating clamp 5 of the anode chamber, and the anode chamber 6.

[0030] Example

[0031] To expel bubbles as quickly as possible and minimize the impact of gas on experimental testing, the testing device of this invention is longitudinally arranged. From front to back, the reaction cell components are a cover plate, optical glass, cathode chamber, insulating clamp between the cathode chamber and cathode chamber, and gas chamber. From left to right, the reaction cell components are a cathode chamber, insulating clamp between the anode chamber, and anode chamber. The light beam of the Raman spectrometer, which is compatible with the electrolytic cell device of this embodiment, can be projected from the optical glass into the cathode chamber of the electrochemical cell, and the Raman scattering signal is obtained after reflection from the sample under test on the working electrode.

[0032] The electrolytic cell has a reference electrode and threaded pipes inside. The gas path, liquid path, and high-pressure reference electrode are all screwed in from the outside to the inside through one side of the main body of the reaction cell to achieve stability under high pressure. Each part of the reaction cell has a sealing ring groove to achieve a sealing effect. The use of stainless steel or titanium alloy and the reasonable application of sealing rings meet the pressure resistance requirements of the reaction cell. By adding grooves and bosses inside the cathode chamber, the thickness of the electrolyte can be flexibly adjusted to adapt to the optical characteristics of the Raman spectrometer, and high signal-to-noise ratio Raman signals can be obtained in different pressure ranges.

[0033] The in-situ Raman testing method for high-voltage flow three-phase interfaces in this embodiment includes the following steps:

[0034] (1) The in-situ Raman testing device is placed on the reaction cell support platform of the Raman testing system;

[0035] (2) Install the gas diffusion electrode, high-voltage reference electrode and counter electrode respectively, and connect the high-voltage pipeline;

[0036] (3) During the electrocatalytic reaction, CO or CO2 gas is introduced into the gas chamber at a flow rate of 20 sccm. 10 mL of electrolyte is introduced into both the cathode and anode chambers, and a high-pressure peristaltic pump is used to circulate the electrolyte between the cathode and anode chambers at a flow rate of 10 mL / min. Alligator clips on the electrochemical workstation are connected to the counter electrode, high-voltage reference electrode, and gas diffusion electrode, respectively. The parameters of the electrochemical workstation are then set.

[0037] (4) The reaction progress on the electrode surface was observed through optical glass, and Raman spectral signals were collected during the electrocatalytic reaction.

[0038] Those skilled in the art will readily understand that the above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. An in-situ Raman testing device suitable for high-voltage flow three-phase interfaces, characterized in that, It includes a gas chamber (1), a cathode chamber insulating clamp (2), a cathode chamber (3), a cover plate (4), an anode chamber insulating clamp (5), and an anode chamber (6); the cathode chamber insulating clamp (2) is located between the gas chamber (1) and the cathode chamber (3); a gas hole is opened in the center of the gas chamber (1), and a gas diffusion electrode is arranged between the cathode chamber insulating clamp (2) and the cathode chamber (3). The size of the gas diffusion electrode covers the gas hole. The gas chamber (1) includes an inlet hole (1-1) and an outlet hole (1-4). Most of the gas is directly discharged outside the gas chamber through the outlet hole (1-4), and a small part of the gas enters the gas diffusion electrode through the gas hole. An electrocatalytic reaction occurs; the cathode chamber (3) is provided with an electrode groove and a high-voltage reference electrode is configured; the cathode chamber (3) has an inlet (3-1); the cathode chamber (3) and the cover plate (4) have a central opening and are inlaid with optical glass (7); the anode chamber insulating clamp (5) and the anode chamber (6) are vertically placed together with the gas chamber (1), the cathode chamber insulating clamp (2), the cathode chamber (3), and the cover plate (4); a counter electrode is provided between the anode chamber insulating clamp (5) and the anode chamber (6); the anode chamber (6) has an outlet (6-2); the contact parts of each component are provided with sealing ring grooves, and a closed pressure-resistant system is formed by fastening the sealing rings. During operation, electrolyte is introduced through the inlet (3-1), flows in the cathode chamber (3) and the anode chamber (6), and then flows out from the outlet (6-2); gas is introduced into the gas chamber (1), and an electrocatalytic reaction occurs at the gas diffusion electrode. The changes in the gas diffusion electrode reaction are observed through the optical glass (7), and Raman spectral signals during the electrocatalytic reaction process are collected.

2. The apparatus as claimed in claim 1, characterized in that, The pressurization of the air chamber is achieved through a back pressure valve.

3. The apparatus as described in claim 1, characterized in that, The cathode chamber (3) has a boss (3-5) in the middle for receiving optical glass.

4. The apparatus as claimed in claim 1, characterized in that, Liquid circulation is achieved through a high-pressure circulating pump.

5. The apparatus as claimed in claim 1, characterized in that, The sealing grooves include a gas chamber sealing groove (1-3) connecting the gas chamber (1) and the cathode chamber insulating clamp (2), a cathode chamber insulating clamp first sealing groove (2-1), a cathode chamber insulating clamp second sealing groove (2-2) connecting the cathode chamber insulating clamp (2) and the cathode chamber (3), a cathode chamber first sealing groove (3-3), a cathode chamber second sealing groove (3-8) connecting the cathode chamber (3) and the anode chamber insulating clamp (5), a cathode chamber third sealing groove (3-4) connecting the cathode chamber (3) and the cover plate (4), and a connecting groove between the cathode chamber (3) and the optical glass. The cathode chamber fourth sealing ring groove (3-6) of the glass (7), the cover plate first sealing ring groove (4-1) connecting the cathode chamber (3) and the cover plate (4), the cover plate second sealing ring groove (4-2) connecting the cover plate (4) and the optical glass (7), the anode chamber insulating clamp first sealing ring groove (5-1) connecting the cathode chamber (3) and the anode chamber insulating clamp (5), the anode chamber insulating clamp second sealing ring groove (5-2) connecting the anode chamber insulating clamp (5) and the anode chamber (6), and the anode chamber sealing ring groove (6-1) connecting the anode chamber insulating clamp (5) and the anode chamber (6).

6. The apparatus as claimed in claim 5, characterized in that, All of the sealing ring grooves are O-ring grooves.

7. The apparatus as claimed in claim 1, characterized in that, The high-voltage reference electrode is one or more of the following: silver chloride electrode, Hg / HgO mercuric oxide electrode, and saturated calomel cell.

8. The apparatus as claimed in claim 1, characterized in that, The gas chamber (1), cathode chamber (3), cover plate (4) and anode chamber (6) are all made of stainless steel or titanium alloy.

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