An experimental device for variable-temperature electrochemical Raman spectroscopy characterization

Abstract

The present invention provides an experimental device for variable-temperature electrochemical Raman spectroscopy characterization, which relates to a device facilitating optical testing and Raman scattering. The experimental device of the present invention includes a hot and cold stage assembly, an electrolytic cell assembly, a circulating water tank air pump assembly, and an electronic control assembly. The present invention adopts a two-stage refrigeration technology (the cold end of the thermoelectric cooler refrigerates + the cooling medium is cooled by the refrigeration part and then introduced into the water-cooled head), effectively solving the problem of limited high-precision interfacial spectroscopy imaging caused by the vibration of the small Dewar system in the prior art, and overcoming the bottleneck of low efficiency of single thermoelectric refrigeration and difficulty in achieving long-term ultra-low temperature control. The present invention designs a new type of Raman electrolytic cell suitable for (high) low-temperature electrochemical experiments, which has a compact structure, high heat conduction efficiency, small heat dissipation loss, and a structure reserved for low-temperature potential correction, and is effectively applicable to this low-temperature hot and cold platform. After fine-tuning by relevant technical personnel in the field, it can be effectively applicable to other (high) low-temperature devices on the market.

Description

Technical Field

[0001] The present invention relates to testing or analyzing materials by measuring the chemical or physical properties of the materials, to devices or instruments facilitating optical testing, to Raman scattering, to components of an electrolytic cell, and particularly to an experimental device for variable-temperature electrochemical Raman spectroscopy characterization. Background Art

[0002] The research on variable-temperature electrochemistry (temperature range approximately -120 °C to 80 °C) and variable-temperature energy storage devices is an important research field at present. In particular, the recent research on low-temperature battery materials (such as low-temperature electrolytes) has attracted much attention, which also poses an urgent demand for in-situ characterization under variable-temperature conditions, especially for low-temperature electrochemical systems. As a powerful characterization tool, Raman spectroscopy has become a commonly used means for the research of energy materials and interfacial processes because it can provide vibrational spectral information and can be combined with electrochemical research techniques.

[0003] In order to achieve Raman spectroscopy testing under variable-temperature conditions, the prior art mainly adopts the following several schemes:

[0004] (1) A variable-temperature hot and cold stage based on a Dewar system. Such devices usually use liquid gases such as liquid nitrogen or liquid helium as cooling media and can achieve extremely low temperatures. There are already various (high) low-temperature devices on the market that can be combined with a Raman spectrometer based on this principle. However, this scheme has the following significant disadvantages: it is difficult to be combined with an electrochemical device. The existing commercially available devices based on the Dewar system are usually designed for low-temperature Raman research on simple solid, powder or liquid samples, lacking interfaces and functions for combination with electrochemical devices and being difficult to meet the requirements of in-situ characterization of low-temperature electrochemical Raman; the device structure is complex and difficult to improve. The Dewar system has a relatively complex structure, and it is difficult for users to improve it according to their own research needs, such as connecting electrochemical equipment or other combined equipment, which limits the flexibility of experiments; and there are vibration problems. Especially for small Dewar systems, the sample stage often has irregular vibrations during use, seriously affecting high-precision interfacial research. For example, during high-resolution imaging or micro-area Raman testing, vibrations will cause image blurring or spectral signal distortion.

[0005] (2) High- and low-temperature devices based on semiconductor refrigeration. Such devices use semiconductor refrigeration chips for refrigeration and have advantages such as high temperature control accuracy and fast response speed. However, this scheme also has obvious limitations: it is difficult to reach lower temperatures. Single-stage or simple multi-stage semiconductor refrigeration usually cannot reach lower temperatures, such as below -40 °C, which limits its application in low-temperature electrochemical research that requires lower temperatures; and the refrigeration efficiency is relatively low. In the low-temperature section, the efficiency of semiconductor refrigeration will decrease significantly, resulting in high energy consumption and being difficult to maintain a stable low-temperature state.

[0006] (3) (High) low-temperature devices based on air compression refrigeration. Such devices refrigerate by compressing refrigerant gas and can achieve relatively low temperatures. However, this solution also has deficiencies: the temperature control accuracy is poor. Compared with semiconductor refrigeration, the temperature control accuracy of air compression refrigeration is relatively low and it is difficult to meet the requirements of high-precision low-temperature electrochemistry research.

[0007] In summary, there are many deficiencies in the prior art in realizing the combined use of variable-temperature electrochemistry and Raman. These deficiencies mainly focus on aspects such as the connectivity of the device, operation safety, temperature control range and accuracy, and vibration control.

[0008] Therefore, developing a device that can effectively overcome the above shortcomings and realize variable-temperature electrochemical Raman spectroscopy testing in the range of -120 °C to 80 °C is of great significance for in-depth research in fields such as variable-temperature energy chemistry, low-temperature electrochemistry, and low-temperature energy storage devices. Summary of the Invention

[0009] The present invention is made to solve the above problems, and the purpose is to provide an experimental device for variable-temperature electrochemical Raman spectroscopy characterization.

[0010] The present invention provides an experimental device for variable-temperature electrochemical Raman spectroscopy characterization, which has the following characteristics: it includes a thermoelectric cooler assembly, an electrolytic cell assembly, a circulating water tank air pump assembly, and an electronic control assembly. Inside the thermoelectric cooler assembly, there is a water-cooling head, a Peltier cooler connected to the water-cooling head, and a heating sheet connected to the water-cooling head. On the outer surface of the thermoelectric cooler assembly, there is a first optical window. The electrolytic cell assembly is arranged inside the thermoelectric cooler assembly and on the Peltier cooler. The electrolytic cell assembly conducts electrochemical experiments through a counter electrode, a working electrode, and a reference electrode sealed inside it. On the outer surface of the electrolytic cell assembly, there is a second optical window. The electrolytic cell assembly is used to conduct Raman spectroscopy characterization experiments through the first optical window and the second optical window. The circulating water tank air pump assembly includes: a cooling medium circulation component, connected and communicated with the water-cooling head, for providing circulating cooling medium to the water-cooling head, and a gas supply component, connected to the cooling medium circulation component and the thermoelectric cooler assembly, for purging the dried gas cooled by the cooling medium in the cooling medium circulation component to the upper surface of the first optical window to prevent it from frosting or fogging; the electronic control assembly includes: a DC regulated power supply, connected to the Peltier cooler and the heating sheet and supplying power to them, an AC power supply, connected to the circulating water tank air pump assembly and supplying power to it, a plurality of temperature sensors, respectively arranged on the water-cooling head, the Peltier cooler, the heating sheet, and the electrolytic cell assembly, two temperature controllers, respectively arranged on the power supply lines of the water-cooling head and the Peltier cooler, for controlling the operating power of the water-cooling head and the Peltier cooler, a high liquid level sensor, arranged in the cooling medium circulation component, for detecting the liquid level height of the cooling medium stored in the cooling medium circulation component, a plurality of current / voltage sensors, arranged on the output lines of the DC regulated power supply and the AC power supply, for detecting the current / voltage signals of the DC regulated power supply and the AC power supply, a plurality of circuit switches, arranged on different circuits, and a controller, connected to the temperature sensors, the temperature controllers, the high liquid level sensor, the current / voltage sensors, and the circuit switches, for dynamically adjusting the working states of the circulating water tank air pump assembly and / or the thermoelectric cooler assembly according to a preset strategy based on voltage / current data, different temperature data, and liquid level height data.

[0011] In the experimental device for variable-temperature electrochemical Raman spectroscopy characterization provided by the present invention, it may also have the following characteristics: among them, the Peltier cooler is arranged above the water-cooling head, and a heat-conducting medium is filled between the Peltier cooler and the water-cooling head. The heating sheet is arranged below the water-cooling head, and a heat-conducting medium is filled between the heating sheet and the water-cooling head.

[0012] In the experimental device for variable-temperature electrochemical Raman spectroscopy characterization provided by the present invention, it may also have the following characteristics: among them, a liquid guide pipe is externally connected to the water-cooling head, and the liquid guide pipe is communicated with the cooling medium circulation component, so that the cooling medium circulation component circulates and transports the cooling medium to the water-cooling head through it.

[0013] In the experimental apparatus for variable-temperature electrochemical Raman spectroscopy characterization provided by the present invention, it may further have the following feature: A heat-insulating tube for reducing heat loss is wrapped around the outer periphery of the liquid guide tube.

[0014] In the experimental apparatus for variable-temperature electrochemical Raman spectroscopy characterization provided by the present invention, it may further have the following feature: The electrolytic cell assembly includes: An electrolytic cell body having an inwardly recessed open slot, and a cylindrical protrusion protruding inside the open slot; A working electrode connecting member passing through the cylindrical protrusion and connected to an electrochemical workstation through a wire outside the electrolytic cell assembly; A working electrode disposed on the cylindrical protrusion and connected to the working electrode connecting member, the working electrode being located inside the open slot; A reference electrode disposed in the open slot and connected to an external electrochemical workstation through a wire passing through the electrolytic cell body; A counter electrode disposed in the open slot and connected to an external electrochemical workstation through a wire passing through the electrolytic cell body, the counter electrode surrounding the working electrode; An electrolytic cell cover detachably disposed on the electrolytic cell body and completely covering the open slot, the electrolytic cell cover having a second optical window; And a sealing ring disposed between the electrolytic cell body and the electrolytic cell cover to ensure the sealing between the two.

[0015] In the experimental apparatus for variable-temperature electrochemical Raman spectroscopy characterization provided by the present invention, it may further have the following feature: The electrolytic cell body is made of a material with corrosion resistance and low-temperature stability, the optical window is made of a material with high transmittance, low fluorescence background and good chemical stability, the counter electrode is a metal wire with high conductivity and chemical stability, the working electrode connecting member is made of a material with high conductivity, corrosion resistance and mechanical strength, the reference electrode is a metal wire quasi-reference electrode, and the sealing ring is an elastic material with corrosion resistance and low-temperature sealing performance.

[0016] In the experimental apparatus for variable-temperature electrochemical Raman spectroscopy characterization provided by the present invention, it may further have the following feature: The cooling medium circulation member includes: A circulation water tank filled with a cooling medium inside, the circulation water tank being connected to a water-cooled head to deliver the circulating cooling medium to the water-cooled head; A refrigeration part connected to the circulation water tank to cool the cooling medium; And a circulation pump disposed on the path connecting the circulation water tank and the water-cooled head to provide power for the circulation of the cooling medium.

[0017] In the experimental apparatus for variable-temperature electrochemical Raman spectroscopy characterization provided by the present invention, it may further have the following feature: The cooling medium circulation member further includes: A stirrer connected to the circulation water tank and stirring the cooling medium therein; And a heat-insulating layer at least covering the circulation water tank to reduce the heat loss of the cooling medium.

[0018] In the experimental apparatus for variable-temperature electrochemical Raman spectroscopy characterization provided by the present invention, it may further have the following characteristics: Among them, the gas supply component includes: a gas supply pipeline, one end of which is communicated with the atmosphere, the other end is connected and communicated with the hot and cold stage assembly and the pipe orifice is located beside the first optical window, and at least a part of the pipe body of the gas supply pipeline is immersed in the cooling medium; a gas pump, arranged on the gas supply pipeline, for providing blowing cold air to the first optical window through the gas supply pipeline; and a dryer, arranged on the gas supply pipeline, for drying the cold air conveyed by it.

[0019] In the experimental apparatus for variable-temperature electrochemical Raman spectroscopy characterization provided by the present invention, it may further have the following characteristics: Among them, the electronic control component further includes a gas flow meter and a gas flow control valve. The gas flow meter and the gas flow control valve are arranged on the gas supply pipeline and connected to the controller. The controller also controls the gas flow control valve according to the data transmitted by the gas flow meter according to a predetermined strategy.

[0020] The present invention provides an improved solution for low-temperature electrochemical Raman testing, significantly improving the performance and applicability of low-temperature electrochemical Raman testing, and having the following beneficial effects:

[0021] (1) In terms of the refrigeration system, the present invention adopts a two-stage refrigeration technology (the cold end of the thermoelectric cooler refrigerates + the refrigeration part cools the cooling medium and then passes it into the water-cooled head), effectively solving the problem that the high-precision interface spectroscopy imaging is limited by the vibration of the small Dewar system in the prior art, and overcoming the bottleneck of the low efficiency of single thermoelectric refrigeration and the difficulty in achieving long-term ultra-low temperature control. Specifically, the present invention uses the refrigeration part to provide low-temperature circulating coolant (cooling medium) to efficiently dissipate heat from the hot end of the thermoelectric cooler, greatly improving the refrigeration efficiency. In theory, precise control over an ultra-wide temperature range from -120 °C to 80 °C can be achieved. Compared with the traditional small liquid nitrogen Dewar system, the device of the present invention significantly reduces vibration interference, improves the accuracy and resolution of spectroscopy imaging; at the same time, the device of the present invention does not need to frequently replenish liquid nitrogen, is more convenient to operate, and reduces the experimental cost and maintenance cost. Compared with the single thermoelectric refrigeration system, the device of the present invention expands the temperature control range and can achieve lower test temperatures.

[0022] (2) In terms of the design of the electrolytic cell, the present invention designs a new type of Raman electrolytic cell suitable for (high) low-temperature electrochemical experiments. The electrolytic cell has a compact structure, high heat conduction efficiency, small heat dissipation loss, and a structure for low-temperature potential correction is reserved, which can be effectively applied to this low-temperature hot and cold platform, or can be effectively applied to other (high) low-temperature devices on the market after being slightly adjusted by relevant technical personnel in the field.

[0023] (3) The present invention provides alternative reference solutions for different experimental requirements and reserves room for upgrading. Users can flexibly select appropriate equipment configurations according to the specific requirements of their own experiments, improving the versatility and applicability of the device, meeting the personalized needs of different users, and reducing the experimental costs of users.

[0024] (4) Through improvements in aspects such as the refrigeration system, electrolytic cell design, and equipment scheme selection, the present invention effectively solves the deficiencies existing in the prior art in low-temperature electrochemical Raman testing, significantly improving the accuracy, efficiency, convenience, and applicability of testing. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 are the perspective view and top view of the hot and cold stage assembly in the embodiment of the present invention.

[0026] Figure 2 is the top view of the electrolytic cell assembly in the embodiment of the present invention.

[0027] Figure 3 is the structural schematic diagram of the circulating water tank air pump assembly in the embodiment of the present invention.

[0028] Figure 4 is the connection relationship schematic diagram of the electric control assembly in the embodiment of the present invention.

[0029] Figure 5 is Figure 1 the front view cross-sectional view at the A-A' line in

[0030] Figure 6 is Figure 2 the front view exploded cross-sectional view at the B-B' line in DETAILED DESCRIPTION OF THE EMBODIMENTS

[0031] In order to make the technical means, creative features, achieved purposes, and functions of the present invention easy to understand, the following embodiments will specifically elaborate on an experimental device for variable-temperature electrochemical Raman spectroscopy characterization of the present invention in conjunction with the drawings.

[0032] <Embodiment>

[0033] Figure 1 are the perspective view and top view of the hot and cold stage assembly in the embodiment of the present invention; Figure 2 is the top view of the electrolytic cell assembly in the embodiment of the present invention; Figure 3 is the structural schematic diagram of the circulating water tank air pump assembly in the embodiment of the present invention; Figure 4 is the connection relationship schematic diagram of the electric control assembly in the embodiment of the present invention.

[0034] As Figures 1 to 4As shown in the figure, this embodiment provides an experimental device 100 for variable-temperature electrochemical Raman spectroscopy characterization, including a thermostatic stage assembly 10, an electrolytic cell assembly 20, a circulating water tank air pump assembly 30, and an electric control assembly 40.

[0035] Figure 5 is Figure 1 The main view cross-sectional view at the A-A' line in the figure.

[0036] As Figure 1 and Figure 5 As shown in the figure, the thermostatic stage assembly 10 includes a housing 11, a heating sheet 12, a water-cooled head 13, and a refrigeration sheet 14.

[0037] The housing 11 is used to support internal components, provide certain heat insulation performance, and form a relatively enclosed space.

[0038] The housing 11 is divided into a test area 111 and a storage area 112 by a grid plate 11a inside it, and the atmospheres of the test area 111 and the storage area 112 are connected.

[0039] The top removable cover plate of the test area 111 has a first optical window 111a, and the side wall of the test area 111 has several through holes for threading lines and / or pipelines. Among them, when the corresponding through holes are not in use, they are closed by removable sealing plugs 111b.

[0040] The storage area 112 has a removable cover plate, and its interior is used to place desiccants and sensors required for experiments.

[0041] The heating sheet 12 is arranged at the inner bottom of the test area 111. Specifically, in this embodiment, the heating sheet 12 is an alumina ceramic heating sheet or a resistance wire heating sheet.

[0042] The water-cooled head 13 is arranged on the heating sheet 12, and a heat-conducting medium is filled between the water-cooled head 13 and the heating sheet 12 to improve the heat conduction efficiency and reduce the thermal resistance.

[0043] The water-cooled head 13 has an integrally formed water inlet pipe 13a and a water outlet pipe 13b. Both the water inlet pipe 13a and the water outlet pipe 13b pass through the inner bottom of the test area 111. The water inlet pipe 13a and the water outlet pipe 13b are respectively used for the cooling medium to flow into and out of the water-cooled head 13.

[0044] The water inlet pipe 13a and the water outlet pipe 13b are respectively connected to two liquid guide pipes, and the outer periphery of the liquid guide pipes is coated with a heat-insulating pipe for reducing heat loss. When the cooling medium is a water-based coolant (water, brine), the liquid guide pipe material includes silica gel pipes and rubber pipes; when the cooling medium is an organic solvent, the liquid guide pipe material is a hose material resistant to organic solvent corrosion, including fluororubber pipes; in this embodiment, when performing a low-temperature electrochemical Raman spectroscopy experiment, in order to improve the stability and durability of the device, the liquid guide pipes are selected as silica gel pipes.

[0045] The thermoelectric cooler 14 is disposed on the water-cooled head 13. The hot end of the thermoelectric cooler 14 is in contact with the water-cooled head 13, so that the water-cooled head 13 cools it down. A heat-conducting medium is filled between the thermoelectric cooler 14 and the water-cooled head 13 to improve the heat-conducting efficiency and reduce the thermal resistance.

[0046] Specifically, in this embodiment, the thermoelectric cooler 14 is a semiconductor thermoelectric cooler, and different models and grades of thermoelectric coolers (single-stage, two-stage to five-stage semiconductor thermoelectric coolers) are selected according to the required cooling capacity.

[0047] Among the above heating sheet 12, water-cooled head 13 and thermoelectric cooler 14, the water-cooled head 13 is used to transfer the heat generated by the thermoelectric cooler 14 and the heating sheet 12 to the cooling medium therein.

[0048] Figure 6 Yes Figure 2 The main-view sectional exploded view at the B-B' line in

[0049] As Figure 2 And Figure 6 shown, the electrolytic cell assembly 20 includes an electrolytic cell body 21, a working electrode connecting member 22, a working electrode 23, a reference electrode 24, a counter electrode 25, an electrolytic cell cover 26, a sealing ring 27 and an electrolytic cell cover reinforcing member 28.

[0050] The electrolytic cell body 21 has an inwardly recessed opening groove 21a, and a cylindrical protrusion 21b protrudes inside the opening groove 21a. The electrolytic cell body 21 is disposed above the cold end of the thermoelectric cooler 14, and the electrolytic cell body 21 is made of a material with corrosion resistance and low-temperature stability.

[0051] Specifically, in this embodiment, the electrolytic cell body 21 is generally cylindrical. The material of the electrolytic cell body 21 is polytetrafluoroethylene (PTFE) or polyether ether ketone (PEEK), which has excellent corrosion resistance and low-temperature stability and can effectively resist the erosion of the electrolyte and the influence of the low-temperature environment.

[0052] The side wall of the electrolytic cell body 21 has four reserved holes with a pore diameter of 0.5 mm, which are respectively denoted as the first reserved hole, the second reserved hole, the third reserved hole and the fourth reserved hole.

[0053] The working electrode connecting member 22 is inserted into the cylindrical protrusion 21b and is connected to the electrochemical workstation through a wire outside the electrolytic cell assembly 20. The working electrode connecting member 22 is made of a material with high electrical conductivity, corrosion resistance and mechanical strength, which can realize reliable connection with the working electrode 23 and electrical signal transmission, and minimize the interference with the electrochemical test.

[0054] Specifically, in this embodiment, the material of the working electrode connecting member 22 is pure titanium, titanium alloy, gold, silver or copper.

[0055] The working electrode 23 is disposed on the cylindrical protrusion 21b and connected to the working electrode connecting member 22. The working electrode 23 is located inside the opening groove 21a.

[0056] Specifically in this embodiment, the selection of the specific material of the working electrode connecting member 22 should be comprehensively considered according to the material of the working electrode 23 and the type of the electrolyte, so as to prevent the working electrode connecting member 22 from participating in the electrochemical reaction or undergoing electrochemical corrosion with the working electrode 23. The material of the working electrode connecting member 22 is preferably the same as that of the working electrode 23.

[0057] The reference electrode 24 is disposed in the opening groove 21a and connected to an external electrochemical workstation through a wire passing through the first reserved hole in the side wall of the electrolytic cell body 21.

[0058] Under non-extreme temperature conditions, traditional reference electrodes can be selected, such as silver / silver chloride electrode (Ag / AgCl), saturated calomel electrode (SCE), etc. However, under high and low temperature environments, the potential of traditional reference electrodes is greatly affected by temperature, and the supporting electrolyte of the reference electrode is prone to freezing in extremely low temperature environments, resulting in the inability of traditional reference electrodes to work properly. Therefore, in this embodiment, a metal wire is selected as the quasi-reference electrode (QRE), including platinum wire or gold wire, and the reference electrode potential is quickly corrected through the fourth reserved hole.

[0059] When using the reference electrode 24, its potential will drift to a certain extent with the experimental conditions. To obtain an accurate potential reference, the reference electrode 24 needs to be corrected.

[0060] The correction methods include: (1) Using a room temperature reference electrode for correction: Utilizing the fourth reserved hole, measure the potential difference between the reference electrode at room temperature (such as Ag / AgCl reference electrode) and the quasi-reference electrode at low temperature in the same system, so as to obtain a more accurate electrode potential in this system at the test temperature. (2) Designing a low temperature reference electrode: In order to obtain a more stable potential reference at low temperature, a reference electrode suitable for low temperature environment is designed by oneself. For example, in the silver / silver chloride electrode, the saturated potassium chloride solution is replaced with other electrolyte solutions with lower freezing points, such as lithium chloride, lithium salt of acetonitrile, etc. This method can effectively lower the lower limit of the operating temperature of the reference electrode. (3) According to the specific experimental conditions and temperature range, select a suitable reference electrode or quasi-reference electrode, and adopt corresponding correction methods to ensure the accuracy of potential measurement.

[0061] The counter electrode 25 is disposed in the opening groove 21a and is connected to an external electrochemical workstation through a wire passing through a second reserved hole in the side wall of the electrolytic cell body 21. The counter electrode 25 surrounds the working electrode 23 to provide a uniform current distribution. The counter electrode 25 is made of a material with high electrical conductivity and chemical stability, and the counter electrode 25 is a gold wire, a silver wire, glassy carbon, a platinum wire or stainless steel. Specifically, in this embodiment, the counter electrode 25 is a platinum wire with a diameter of 0.5 mm.

[0062] The electrolytic cell cover 26 is detachably disposed on the electrolytic cell body 21 and completely covers the opening groove 21a. The electrolytic cell cover 26 has a second optical window 26a. The second optical window 26a is made of a material with high transmittance, low fluorescence background and good chemical stability.

[0063] Specifically, in this embodiment, the material of the second optical window 26a is sapphire (Al2O3), fused quartz (SiO2), ultraviolet-grade fused quartz (JGS1), calcium fluoride (CaF2) or zinc selenide. Among them, the sapphire (Al2O3) material has high transmittance in the ultraviolet-visible-near-infrared band, and does not produce fluorescence background interference by itself, which can meet the requirements of Raman spectroscopy testing. At the same time, sapphire (Al2O3) has excellent chemical stability and mechanical strength, as well as good low-temperature performance; fused quartz and ultraviolet-grade fused quartz (JGS1) also have good transmittance and low fluorescence background in the deep ultraviolet to visible band, but their mechanical strength and corrosion resistance are slightly inferior to sapphire (Al2O3); calcium fluoride (CaF2) has good transmittance, low birefringence and low scattering rate from ultraviolet to mid-infrared, but it is sensitive to temperature changes and has relatively poor mechanical strength; zinc selenide has good transmittance in the mid-infrared band, good transmittance in the mid-infrared band, good mechanical strength and good chemical stability.

[0064] The sealing ring 27 is disposed between the electrolytic cell body 21 and the electrolytic cell cover 26 to ensure the sealing between the two. The sealing ring 27 is an elastic material with corrosion resistance and low-temperature sealing performance.

[0065] Specifically, in this embodiment, the sealing ring 27 is made of fluororubber, which has excellent corrosion resistance and low-temperature sealing performance, and can provide reliable sealing in a low-temperature environment to prevent electrolyte leakage.

[0066] The electrolytic cell cover reinforcement 28 is a circular cover plate that covers the electrolytic cell cover 26 without blocking the second optical window 26a. The electrolytic cell cover 26 and the electrolytic cell body 21 have a number of threaded holes on the edge sides in their axial directions. The electrolytic cell cover reinforcement 28 has a number of countersunk through holes on the edge sides in its axial direction and corresponds to the positions of the number of threaded holes of the electrolytic cell cover 26 and the electrolytic cell body 21. The electrolytic cell cover reinforcement 28, the electrolytic cell cover 26, and the electrolytic cell body 21 are tightly fixed to each other by sequentially passing through the respective bolts 1 and nuts 2 in cooperation with each other, and a sealed space is formed between the electrolytic cell body 21 and the electrolytic cell cover 26 through the sealing ring 27.

[0067] The electrolytic cell assembly 20 is placed entirely above the cold end of the thermoelectric cooler 14, and its second optical window 26a is located below the first optical window 111a. The electrolytic cell assembly 20 is used to perform electrochemical experiments through the counter electrode 25, the working electrode 23, and the reference electrode 24 sealed inside it. At the same time, the user performs Raman spectroscopy characterization on the electrochemical experiments carried out in the electrolytic cell assembly 20 through the first optical window 111a and the second optical window 26a.

[0068] As Figure 3 shown, the circulating water tank air pump assembly 30 includes a housing 31, a cooling medium circulating member 32, and a gas supply member 33.

[0069] The housing 31 serves as an overall enclosure for the circulating water tank air pump assembly 30, is used to place various components, protect the internal components, and provide support and fixation. The housing 31 is made of a material with sufficient strength and protective performance.

[0070] Specifically in this embodiment, the housing 31 is made of ABS plastic.

[0071] The cooling medium circulating member 32 includes a circulating water tank 321, a refrigeration part 322, a stirrer 323, a heat insulation layer 324, and a circulating pump 325.

[0072] The circulating water tank 321 is arranged in the housing 31, and a cooling medium is filled inside the circulating water tank 321. The circulating water tank 321 is connected to two liquid guide pipes that are connected to the water inlet pipe 13a and the water outlet pipe 13b, so as to provide the cooling medium to the water-cooled head 13 through the two liquid guide pipes.

[0073] The circulating water tank 321 is a container with corrosion resistance and heat insulation performance. Specifically in this embodiment, the material of the circulating water tank 321 is polytetrafluoroethylene (PTFE).

[0074] The refrigeration part 322 is connected to the circulating water tank 321 to cool the cooling medium therein.

[0075] Specifically, in this embodiment, the refrigeration part 322 selects the compression refrigeration method, which realizes refrigeration through the cyclic phase change of the refrigerant.

[0076] The stirrer 323 is connected to the circulation water tank 321 and stirs the cooling medium therein, so as to ensure the temperature uniformity of the cooling medium inside the circulation water tank 321.

[0077] The heat insulation layer 324 wraps the circulation water tank 321 to reduce the heat loss of the cooling medium therein, reduce heat exchange, and improve the refrigeration efficiency. Specifically, in this embodiment, the heat insulation layer 324 is an adiabatic material.

[0078] The circulation pump 325 is arranged on one of the two liquid guide pipes, and is used to provide the driving force for the circulation of the cooling medium in the circulation loop formed by the circulation water tank 321, the two liquid guide pipes and the water-cooled head 13. The flow rate and lift of the circulation pump 325 are selected according to the cooling requirements of the hot and cold stage assembly 10 and the physical properties such as the viscosity of the cooling medium.

[0079] Specifically, in this embodiment, the circulation pump 325 is a centrifugal pump.

[0080] The air supply part 33 includes an air supply pipeline 331, an air pump 332 and a dryer 333.

[0081] One end of the air supply pipeline 331 is communicated with the atmosphere, and the other end is located beside the first optical window 111a of the test area 111. The pipe body part of the air supply pipeline 331 penetrates through the box wall of the circulation water tank 321 and is immersed in the cooling medium therein.

[0082] The air pump 332 is arranged on the air supply pipeline 331 and is used to provide the cold air cooled by the cooling medium to blow on the first optical window 111a through the air supply pipeline 331.

[0083] Specifically, in this embodiment, the air pump 332 is a diaphragm pump.

[0084] The dryer 333 is arranged on the air supply pipeline 331 and is used to dry the cold air conveyed by it.

[0085] Specifically, in this embodiment, the dryer 333 is a dryer filled with desiccant.

[0086] The above air supply pipeline 331, air pump 332 and dryer 333 cooperate with each other so that the dry gas blows on the upper surface of the first optical window 111a to prevent its surface from condensing or frosting.

[0087] As Figure 4As shown, the electronic control component 40 includes a DC regulated power supply 41, an AC power supply 42, a temperature sensor 43, a temperature controller 44, a circuit switch, an Rs485 to USB converter, a high liquid level sensor 45, a current / voltage sensor 46, a gas flow meter 47, a gas flow control valve 48, and a controller 49.

[0088] The DC regulated power supply 41 is connected to the cooling fin 14 and the heating fin 12 and supplies power to them.

[0089] The AC power supply 42 is connected to the circulation pump 325 and the air pump 332 and supplies power to them.

[0090] The temperature sensor 43 includes a first temperature sensor 431, a first temperature transmitter 432, a second temperature sensor 433, a second temperature transmitter 434, a third temperature sensor 435, a third temperature transmitter 436, a fourth temperature sensor 437, and a fourth temperature transmitter 438.

[0091] The first temperature sensor 431, the second temperature sensor 433, the third temperature sensor 435, and the fourth temperature sensor 437 are all thermocouple temperature measurement wires and are respectively arranged on the cooling fin 14, the heating fin 12, the water-cooled head 13, and the opening groove 21a. Among them, the fourth temperature sensor 437 passes through the third reserved hole on the side wall of the electrolytic cell body 21 and extends into the opening groove 21a.

[0092] Specifically, in this embodiment, the first temperature sensor 431, the second temperature sensor 433, the third temperature sensor 435, and the fourth temperature sensor 437 are T-type thermocouples, K-type thermocouples, Pt100, or thermal resistors.

[0093] The first temperature transmitter 432, the second temperature transmitter 434, the third temperature transmitter 436, and the fourth temperature transmitter 438 are respectively connected to the first temperature sensor 431, the second temperature sensor 433, the third temperature sensor 435, and the fourth temperature sensor 437, and have linearization and cold-junction compensation functions, and are used to convert the signals of the thermocouple temperature measurement wires into standard electrical signals.

[0094] The temperature controller 44 includes a first temperature controller 441 and a second temperature controller 442. The first temperature controller 441 is arranged on the line connecting the DC regulated power supply 41 and the cooling fin 14. The second temperature controller 442 is arranged on the line connecting the DC regulated power supply 41 and the heating fin 12. The first temperature controller 441 and the second temperature controller 442 are respectively used to control the operating power of the cooling fin 14 and the heating fin 12.

[0095] The number of circuit switches is several and they are arranged on different lines (not shown in the figure) and are used to open and close according to a preset strategy.

[0096] The Rs485-to-USB converter is connected to the first temperature transmitter 432, the second temperature transmitter 434, the third temperature transmitter 436, the fourth temperature transmitter 438, the first temperature controller 441, and the second temperature controller 442, and is used to transmit temperature data to a computer through a USB interface, so as to remotely monitor the temperature and control the first temperature controller 441 and the second temperature controller 442 through the computer.

[0097] The high liquid level sensor 45 is arranged in the circulation water tank 321 and is used to detect the high liquid level of the cooling medium stored therein.

[0098] The current / voltage sensor 46 includes a first current / voltage sensor 461 and a second current / voltage sensor 462, which are respectively arranged on the output lines of the DC regulated power supply 41 and the AC power supply 42, and are used to detect the current / voltage signals of the DC regulated power supply 41 and the AC power supply 42.

[0099] The gas flowmeter 47 is arranged on the gas supply pipeline 331 and is used to detect the gas flow rate conveyed therein.

[0100] The gas flow control valve 48 is arranged on the gas supply pipeline 331 and is used to control the gas flow rate conveyed therein.

[0101] The controller 49 is a PLC, a single-chip microcomputer, or an industrial control computer carrying a preset strategy, and the control algorithm is a PID algorithm, fuzzy control, or neural network control. The controller 49 is connected to the first temperature transmitter 432, the second temperature transmitter 434, the third temperature transmitter 436, the fourth temperature transmitter 438, the temperature controller 44, the high liquid level sensor 45, the current / voltage sensor 46, the gas flowmeter 47, the gas flow control valve 48, and several circuit switches, and is used to dynamically adjust the working states of the circulation pump 325, the air pump 332, the thermoelectric cooler 14, the heating element 12, the DC regulated power supply 41, and the AC power supply 42 according to the preset strategy based on voltage / current data, different temperature data, liquid level height data, and gas flow rate data.

[0102] Specifically, in this embodiment, the controller 49 is a PLC that uses a PID algorithm for temperature control, and the target temperature control accuracy is ±0.1 °C.

[0103] The usage process of the experimental device 100 for variable-temperature electrochemical Raman spectroscopy characterization:

[0104] First, after adding electrolyte into it through the third reserved hole on the side wall of the electrolytic cell body 21, an electrochemical experiment is started in cooperation with an external electrochemical workstation.

[0105] Subsequently, in the electrochemical experiment, the temperature of the entire electrolytic cell assembly 20 is controlled by the cooperation of the heating sheet 12, the water-cooled head 13, and the thermoelectric cooler 14 in the hot and cold stage assembly 10, and Raman spectroscopy characterization of the electrochemical experiment carried out in the electrolytic cell assembly 20 is performed through the first optical window 111a and the second optical window 26a.

[0106] During the entire electrochemical experiment process, the temperature of the electrolytic cell assembly 20 and the air pump blowing are controlled according to a predetermined strategy through the circulating water tank air pump assembly 30 and the electronic control assembly 40.

[0107] Those skilled in the art should understand that the present invention is not limited by the above embodiments. What is described in the above embodiments and the specification only illustrates the principle of the present invention. Without departing from the spirit and scope of the present invention, the present invention will have various changes and improvements, and these changes and improvements all fall within the scope of the present invention claimed. The scope of the present invention claimed is defined by the appended claims and their equivalents.

Claims

1. An experimental device for variable-temperature electrochemical Raman spectroscopy characterization, characterized in that, It includes a hot and cold stage assembly, an electrolytic cell assembly, a circulating water tank air pump assembly, and an electric control assembly. Inside the hot and cold stage assembly, there is a water-cooled head, a refrigeration chip connected to the water-cooled head, and a heating chip connected to the water-cooled head. On the outer surface of the hot and cold stage assembly, there is a first optical window. The electrolytic cell assembly is arranged inside the hot and cold stage assembly and on the refrigeration chip. The electrolytic cell assembly conducts electrochemical experiments through a counter electrode, a working electrode, and a reference electrode sealed inside it. On the outer surface of the electrolytic cell assembly, there is a second optical window. The electrolytic cell assembly is used to perform Raman spectroscopy characterization experiments through the first optical window and the second optical window. The circulating water tank air pump assembly includes: A cooling medium circulation component, connected and communicated with the water-cooled head, for providing circulating cooling medium to the water-cooled head, and An air supply component, connected to the cooling medium circulation component and the hot and cold stage assembly, for purging the dried gas cooled by the cooling medium in the cooling medium circulation component to the upper surface of the first optical window to prevent frosting or fogging. The electric control assembly includes: A DC regulated power supply, connected to the refrigeration chip and the heating chip and supplying power to them. An AC power supply, connected to the circulating water tank air pump assembly and supplying power to it. Temperature sensors, with several in number, are respectively arranged on the water-cooled head, the refrigeration chip, the heating chip, and the electrolytic cell assembly. Temperature controllers, with 2 in number, are respectively arranged on the power supply lines of the water-cooled head and the refrigeration chip, for controlling the operating power of the water-cooled head and the refrigeration chip. A high liquid level sensor, arranged in the cooling medium circulation component, for detecting the liquid level height of the cooling medium stored in the cooling medium circulation component. Current / voltage sensors, with several in number, are arranged on the output lines of the DC regulated power supply and the AC power supply, for detecting the current / voltage signals of the DC regulated power supply and the AC power supply. Circuit switches, with several in number, are arranged on different circuits. A controller, connected to the temperature sensors, the temperature controllers, the high liquid level sensor, the current / voltage sensors, and the circuit switches, for dynamically adjusting the working states of the circulating water tank air pump assembly and / or the hot and cold stage assembly according to preset strategies based on voltage / current data, different temperature data, and liquid level height data.

2. The experimental device for variable-temperature electrochemical Raman spectroscopy characterization according to claim 1, wherein: Among them, The refrigeration chip is arranged above the water-cooled head, and a heat-conducting medium is filled between the refrigeration chip and the water-cooled head. The heating chip is arranged below the water-cooled head, and a heat-conducting medium is filled between the heating chip and the water-cooled head.

3. The experimental device for variable-temperature electrochemical Raman spectroscopy characterization according to claim 1, wherein: Among them, A liquid guide pipe is connected and communicated to the outer extension of the water-cooled head. The liquid guide pipe is communicated with the cooling medium circulation component, so that the cooling medium circulation component circulates and transports the cooling medium to the water-cooled head through it.

4. The experimental device for variable-temperature electrochemical Raman spectroscopy characterization according to claim 3, wherein: Among them, A heat-insulating tube for reducing heat loss is coated on the outer periphery of the liquid guide tube.

5. The experimental apparatus for variable-temperature electrochemical Raman spectroscopy characterization according to claim 1, It is characterized in that: Wherein, The electrolytic cell assembly includes: An electrolytic cell body having an inwardly recessed open groove, and a cylindrical protrusion protruding in the open groove; A working electrode connecting member is inserted through the cylindrical protrusion and is connected to an electrochemical workstation through a wire outside the electrolytic cell assembly; A working electrode is arranged on the cylindrical protrusion and is connected to the working electrode connecting member, and the working electrode is located inside the open groove; A reference electrode is arranged in the open groove and is connected to an external electrochemical workstation through a wire passing through the electrolytic cell body; A counter electrode is arranged in the open groove and is connected to an external electrochemical workstation through a wire passing through the electrolytic cell body, and the counter electrode surrounds the working electrode; An electrolytic cell cover is detachably arranged on the electrolytic cell body and completely covers the open groove, and the electrolytic cell cover has the second optical window; and A sealing ring is arranged between the electrolytic cell body and the electrolytic cell cover to ensure the sealing between the two.

6. The experimental device for variable-temperature electrochemical Raman spectroscopy characterization according to claim 5, wherein: Among them, The electrolytic cell body is made of a material with corrosion resistance and low-temperature stability, The optical window is made of a material with high transmittance, low fluorescence background and good chemical stability, The counter electrode is a metal wire with high conductivity and chemical stability, The working electrode connecting member is made of a material with high conductivity, corrosion resistance and mechanical strength, The reference electrode is a metal wire quasi-reference electrode, The sealing ring is an elastic material with corrosion resistance and low-temperature sealing performance.

7. The experimental apparatus for variable-temperature electrochemical Raman spectroscopy characterization according to claim 1, It is characterized in that: Wherein, The cooling medium circulation member includes: A circulation water tank filled with a cooling medium, and the circulation water tank is communicated with the water-cooled head to convey the circulating cooling medium to the water-cooled head; A refrigeration part is connected to the circulation water tank to cool the cooling medium; And A circulation pump is arranged on the passage connecting the circulation water tank and the water-cooled head to provide power for the circulation of the cooling medium.

8. The experimental apparatus for variable-temperature electrochemical Raman spectroscopy characterization according to claim 7, It is characterized in that: Wherein, The cooling medium circulation member further includes: A stirrer is connected to the circulation water tank and stirs the cooling medium therein; And A heat-insulating layer at least coats the circulation water tank to reduce the heat loss of the cooling medium.

9. The experimental apparatus for variable-temperature electrochemical Raman spectroscopy characterization according to claim 1, It is characterized in that: Wherein, The gas supply member includes: A gas supply pipeline, one end of which is communicated with the atmosphere, the other end is connected and communicated with the hot and cold stage assembly, and the pipe orifice is located beside the first optical window, and at least part of the pipe body of the gas supply pipeline is immersed in the cooling medium; An air pump is arranged on the gas supply pipeline for providing blowing cold air to the first optical window through the gas supply pipeline; And A dryer is arranged on the gas supply pipeline for drying the cold air conveyed by it.

10. The experimental device for variable-temperature electrochemical Raman spectroscopy characterization according to claim 9, wherein: Among them, The electronic control component further includes a gas flow meter and a gas flow control valve, The gas flow meter and the gas flow control valve are arranged on the gas supply pipeline and connected to the controller, The controller also controls the gas flow control valve according to a predetermined strategy based on the data transmitted by the gas flow meter.

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