An electrochemical experimental device for spectral measurement

Abstract

The invention relates to the field of photochemistry and electrochemistry. An electrochemical experimental device for spectral measurement comprises a high-voltage direct current power supply, a charging resistor, a charging line, a spark switch, a capacitor, a power distributor, an attenuator, a transmission line I, an oscilloscope, a transmission line II, a bracket, a sample cavity, an optical tester, a thermometer, a semiconductor refrigerator, a heat conduction platform and a constant potentiostat. The sample cavity has a compact structure and balances the requirements of electrochemical experiments and spectral experiments. An electrode with a light reflection function makes the light diffusion path shorter, the light scattering is lower, and the signal-to-noise ratio of the spectrum is improved. The device has a specially designed voltage pulse generating circuit and a compact sample cavity. After the sample is subjected to high voltage treatment, the electrochemical characteristics and spectral characteristics of the sample can be studied at the same time. The high-voltage pulse applied to the sample is regular and stable, and the signal-to-noise ratio of the obtained spectrum is improved. The high-voltage pulse generating circuit is relatively simple, and a high voltage can be applied to the sample to perform spectral and electrochemical measurements.

Description

Technical Field

[0001] The invention relates to the fields of photochemistry and electrochemistry, in particular to an electrochemical experimental device for spectral measurement, which can apply high voltage to a sample and perform spectral and electrochemical measurements. Background Art

[0002] The combination of electrochemistry and spectroscopy can be used for substances with redox reaction activity. Usually, the sample is located in the electrochemical chamber, and the sample is irradiated by a laser. An optical tester is used to record the light reflected by the sample to study the characteristics of the reaction. In the prior art, the spectral acquisition time in the measurement of certain reactions is long, and different samples need to be prepared separately for each redox reaction. In some reactions that require the application of high voltage to proceed, especially when a high-voltage pulse is required, the switch needs to be quickly switched between the on and off states. Usually, when the discharge switch is turned on, the charging current will flow from the high-voltage DC power supply to the discharge circuit. This current takes a certain amount of time to completely decay to zero, which will prevent the switch from returning to the off state. The prior art uses special gases or specially designed switch structures to avoid the above phenomenon, but this will make the structure of the device complicated and the operation process cumbersome. Inappropriate experimental operations will produce irregular and unstable voltage pulses. The electrochemical experimental device for spectral measurement can solve the problem. Summary of the invention

[0003] In order to solve the above problems, the present invention has a novel voltage pulse generating circuit and adopts a specially designed sample cavity, so that the electrochemical characteristics and spectral characteristics of the sample can be studied simultaneously after the sample is treated with high voltage.

[0004] The technical solution adopted by the present invention is:

[0005] The electrochemical experimental device for spectral measurement comprises a high-voltage direct current power supply, a charging resistor, a charging line, a spark switch, a capacitor, a power divider, an attenuator, a transmission line I, an oscilloscope, a transmission line II, a bracket, a sample chamber, an optical tester, a thermometer, a semiconductor refrigerator, a heat conduction platform and a constant potentiostat, wherein xyz is a three-dimensional space coordinate system, the high-voltage direct current power supply has a positive output terminal and a negative output terminal, and the output voltage range of the high-voltage direct current power supply is 1 kV to 2 kV, the power divider has an input terminal, an output terminal I and an output terminal II, the constant potentiostat has a positive electrode and a negative electrode, the output terminal II of the power divider is connected to the attenuator, the transmission line I and the oscilloscope in sequence by a cable, and the The sample cavity, the bracket, the semiconductor refrigerator and the heat conduction platform are connected in sequence from top to bottom, the bracket is connected with a thermometer, the optical tester is located directly above the sample cavity, the optical tester can emit laser and perform spectral analysis on the collected light, the laser includes pump light and detection light; the sample cavity includes a cavity, a plane mirror, a working electrode, a counter electrode, a gasket, a sample, a transmission window, a cavity cover, a reference electrode, a joint I and a joint II, the plane mirror, the working electrode, the counter electrode, the gasket, the sample and the transmission window are all located in the cavity, the joint I and the joint II of the sample cavity are respectively connected to the positive and negative poles of the constant potentiostat, the constant potentiostat is located below the sample cavity in the bracket, and the positive pole of the output end of the high-voltage DC power supply is connected in sequence The cable connects the charging resistor, the charging line, the contact II of the spark switch, the rotating shaft of the spark switch, the capacitor and the negative electrode of the output end of the high-voltage DC power supply; the spark switch includes a rotating motor, a rotating shaft, a horizontal rod, a trigger electrode I, two contacts I, a trigger electrode II and two contacts II, the rotating shaft is vertically installed on the rotating motor, the middle of the horizontal rod is connected to the rotating shaft, the length of the horizontal rod is 120 mm, the trigger electrode I and the trigger electrode II are both cubes with a side length of 8 mm, and are respectively installed at both ends of the horizontal rod, the rotating shaft, the horizontal rod, the trigger electrode I and the trigger electrode II are electrically conductive; the two contacts I are the same metal cylinders with their axes along the y direction, and the two contacts I are connected to the trigger electrode II. The two contacts I and II are arranged coaxially, the height of the metal cylinder is 10 mm, the bottom diameter is 10 mm, the distance between the axis of the contact I and the axis of the rotating shaft is 64 mm, the two contacts II are both metal bars in the same 1 / 6 arc shape, the center of the arc is located on the axis of the rotating shaft, and the radius of curvature is 64 mm, the two metal bars are 10 mm apart in the y direction and arranged up and down, the two contacts I are electrically conductive with each other, the two contacts II are electrically conductive with each other, the rotary motor can rotate the horizontal rod in the horizontal plane through the rotating shaft, and the trigger electrode I and the trigger electrode II can pass through the gap between the two contacts I and the gap between the two contacts II without contact;The cavity is a cylindrical barrel with its axis along the y direction. The plane mirror is a cylindrical shape with its axis along the y direction and is located at the bottom of the cavity. The plane mirror has a diameter of 30 mm and is made of polytetrafluoroethylene. The upper surface and side surface of the plane mirror are deposited with a working electrode and a counter electrode. The working electrode and the counter electrode are both made of gold and have a thickness of 500 μm. There are two through holes on the side of the cavity. Connector I and connector II can be in close contact with the working electrode and the counter electrode on the side of the plane mirror through the two through holes respectively. The gasket is made of epoxy resin material and is located on the upper surface of the plane mirror. The outer diameter of the gasket is 30 mm and the inner diameter is 26 mm, typical thickness is 5 to 30 μm, the transmission window is located above the gasket, the diameter of the transmission window is 30 mm, the sample is placed within the inner diameter of the gasket, the cavity cover is installed above the cavity, the cavity cover can transmit light and seal the cavity, the cavity cover can press the transmission window, the gasket and the plane mirror, the cavity cover and the transmission window both have a through hole in the y direction, the reference electrode can be inserted into the sample through the through hole, and the reference electrode is connected to the capacitor, the rotating shaft of the spark switch, the contact I of the spark switch, the input end of the power divider, the output end I of the power divider, the transmission line II and the connector II in sequence. ;

[0006] Principle of applying high voltage pulses to samples:

[0007] The spark switch has two spark gaps, which are used for charging and discharging respectively, and can eliminate irregular and unstable pulses generated by charge discharge in the pulse generating circuit. The rotary motor of the spark switch drives the trigger electrode I and the trigger electrode II to rotate in the horizontal plane through the rotating shaft and the horizontal rod, so that the trigger electrode I and the trigger electrode II alternately pass through the contact I and the contact II in time, and at the same time, the trigger electrode I and the trigger electrode II cannot pass through the contact I and the contact II at the same time, and similarly, the trigger electrode I and the trigger electrode II cannot pass through the contact II and the contact I at the same time. When the trigger electrode I or the trigger electrode II passes through the contact II, the gap between the trigger electrode I or the trigger electrode II and the contact II generates a spark, thereby making the trigger electrode I or the trigger electrode II and the contact II conductive, and the high-voltage DC power supply charges the capacitor; when the trigger electrode I or the trigger electrode II passes through the contact I, the gap between the trigger electrode I or the trigger electrode II and the contact I generates a spark, thereby making the trigger electrode I or the trigger electrode II and the contact I conductive, and the capacitor discharges the sample in the sample chamber.

[0008] Principle of electrochemical measurement of samples:

[0009] The positive electrode and the negative electrode of the potentiostat are connected to the working electrode and the counter electrode respectively through the connector I and the connector II to apply an electrochemical potential to the sample. The sample will have different chemical forms under different electrochemical potentials.

[0010] The principle of spectral experimental measurement of samples:

[0011] The optical tester emits two light pulses, called pump light and detection light. The pump light and detection light have different powers, frequencies and durations. The delay time of the detection light relative to the pump light can be adjusted. The pump light emitted by the optical tester passes through the cavity cover and the transmission window from top to bottom and is shot onto the sample, causing the sample to react. The detection light emitted by the optical tester passes through the cavity cover and the transmission window and is shot onto the sample and produces a certain degree of scattering. A portion of the detection light that is shot onto the upper surface of the working electrode and the counter electrode is reflected to form reflected light. The reflected light is shot onto the sample again from bottom to top, and a portion of the reflected light passes through the sample to form secondary transmitted light. The secondary transmitted light passes through the transmission window and the cavity cover in turn and enters the optical tester. By analyzing the characteristics of the secondary transmitted light collected by the optical tester, the relevant characteristics of the sample can be obtained.

[0012] The laser emitted by the optical tester is incident on the sample at an angle of 0.5 degrees to the normal phase of the upper surface of the transmission window. The advantage is that the light reflected from the upper surface of the transmission window and the light after passing through the sample are spatially separated, thereby avoiding the interference of pump light in the spectrum collected by the optical tester.

[0013] Using a working electrode and a counter electrode made of gold on the upper surface of a plane mirror as the working electrode, rather than using a metal grid as the working electrode as in some spectral measurement devices in the prior art, has the advantage of being able to avoid the problem of light scattering and increase the signal-to-noise ratio of the optical signal collected by the optical tester. In addition, since the light passes through the sample twice, the intensity of the signal collected by the optical tester is doubled, which is very important when the sample amount is small. The present invention only requires less sample for spectral experiments, and the use of thinner samples can reduce the time to reach electrochemical equilibrium, which is very important for some rapid redox cycle processes.

[0014] The structural design of the sample chamber can be suitable for samples of different thicknesses by selecting gaskets of different thicknesses, and has good air tightness.

[0015] Depending on the specific sample being studied, the voltage difference V1 in the following method steps ranges from 0 to 300 mV, and the voltage difference V2 ranges from 300 mV to 800 mV. An embodiment is: for an iron phthalocyanine molecular film sample on a gold substrate surface in an oxygen-saturated electrolyte, the voltage difference V1 is 50 mV, and the voltage difference V2 is 350 mV.

[0016] The steps of conducting an experiment using the electrochemical experimental device for spectral measurement are as follows:

[0017] Step 1, adding a sample into the sample chamber, installing the chamber cover to the chamber body and pressing the transmission window, the gasket and the plane mirror tightly;

[0018] Step 2, turning on the high-voltage DC power supply, outputting voltage to the spark switch through the charging resistor and the charging line, turning on the rotary motor, the speed range of the rotary motor is 1000 to 5000 rpm, the spark switch periodically connects the capacitor to the high-voltage DC power supply or the capacitor to the sample chamber, and the two processes of the high-voltage DC power supply charging the capacitor and the capacitor discharging the sample chamber are alternately performed for 5 minutes;

[0019] Step 3, turn off the high voltage DC power supply and the rotary motor;

[0020] Step 4, turn on the optical tester, so that the laser emitted by the optical tester is incident at an angle of 0.5 degrees to the normal of the upper surface of the transmission window and is incident on the sample, the energy range of each pump light pulse is 4mJ to 8mJ, the duration is 1 picosecond, the energy range of each detection light pulse is 0.5mJ to 1mJ, the duration is 800 femtoseconds, and the time delay of the detection light pulse relative to the pump light pulse is 2 to 5 picoseconds;

[0021] Step 5, adjusting the potentiostat so that the voltage difference between the working electrode and the counter electrode is V1, and the voltage difference V1 ranges from 0 to 300 mV, so as to apply an electrochemical potential to the sample so that the first chemical form appears in the sample, and the optical tester collects the reflected light for 2 minutes;

[0022] Step 6, adjusting the potentiostat so that the voltage difference between the working electrode and the counter electrode is V2, and the voltage difference V2 ranges from 300 mV to 800 mV, so as to apply an electrochemical potential to the sample so that a second chemical form appears in the sample, and the optical tester collects reflected light for 2 minutes;

[0023] Step 7, repeat the above steps 5 and 6, the repetition is performed ten times continuously, the reflected light information collected by the optical tester is processed and averaged to obtain the differential spectrum of the first chemical form and the second chemical form of the sample.

[0024] The beneficial effects of the present invention are:

[0025] The sample chamber structure in the present invention is compact and balances the requirements of electrochemical experiments and spectral experiments. The electrode with light reflection function makes the light diffusion path shorter, the light scattering is lower, and the signal-to-noise ratio of the spectrum is improved. In addition, the high-voltage pulse generation circuit is relatively simple, and the high-voltage pulse applied to the sample is relatively regular and stable. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Further explanation below in conjunction with the graphics of the present invention:

[0027] Figure 1 It is a schematic diagram of the present invention;

[0028] Figure 2It is an enlarged schematic diagram of the spark switch; Figure 3 yes Figure 2 A top view of

[0029] Figure 4 is an enlarged schematic diagram of the sample chamber; Figure 5 yes Figure 4 AA section view.

[0030] In the figure, 1. high voltage DC power supply, 2. charging resistor, 3. charging line, 4. spark switch, 4-1. rotating motor, 4-2. rotating shaft, 4-3. horizontal rod, 4-4. trigger electrode I, 4-5. contact I, 4-6. trigger electrode II, 4-7. contact II, 5. capacitor, 6. power divider, 7. attenuator, 8. transmission line I, 9. oscilloscope, 10. transmission line II, 11. bracket, 12. sample chamber, 12-1. chamber, 12-2. plane mirror, 12-3. working electrode, 12-4. counter electrode, 12-5. gasket, 12-6. sample, 12-7. transmission window, 12-8. chamber cover, 12-9. reference electrode, 12-10. connector I, 12-11. connector II, 13. optical tester, 14. thermometer, 15. semiconductor refrigerator, 16. thermal stage, 17. constant potentiostat. DETAILED DESCRIPTION

[0031] like Figure 1 is a schematic diagram of the present invention, xyz is a three-dimensional space coordinate system, such as Figure 2 This is an enlarged schematic diagram of the spark switch. Figure 3 yes Figure 2A top view of a high-voltage direct current power supply (1), a charging resistor (2), a charging line (3), a spark switch (4), a capacitor (5), a power divider (6), an attenuator (7), a transmission line I (8), an oscilloscope (9), a transmission line II (10), a bracket (11), a sample chamber (12), an optical tester (13), a thermometer (14), a semiconductor refrigerator (15), a heat conduction platform (16) and a constant potentiostat (17), wherein the high-voltage direct current power supply (1) has a positive output terminal and a negative output terminal, and the output voltage range of the high-voltage direct current power supply (1) is 1kV to 2kV, the power distributor (6) has an input end, an output end I and an output end II, the constant potentiostat (17) has a positive electrode and a negative electrode, the output end II of the power distributor (6) is connected to the attenuator (7), the transmission line I (8) and the oscilloscope (9) in sequence by a cable, the sample chamber (12), the bracket (11), the semiconductor refrigerator (15) and the heat conduction platform (16) are connected in sequence from top to bottom, the bracket (11) is connected to a thermometer (14), the optical tester (13) is located directly above the sample chamber (12), and the optical tester (1 3) capable of emitting laser light and performing spectral analysis on the collected light, wherein the laser light includes pump light and detection light; the positive electrode of the output end of the high-voltage DC power supply (1) is connected to the charging resistor (2), the charging line (3), the contact II (4-7) of the spark switch (4), the rotating shaft (4-2) of the spark switch (4), the capacitor (5) and the negative electrode of the output end of the high-voltage DC power supply (1) in sequence through a cable; the spark switch (4) includes a rotating motor (4-1), a rotating shaft (4-2), a horizontal rod (4-3), a trigger electrode I (4-4), two contacts I (4-5) , trigger electrode II (4-6) and two contacts II (4-7), the rotating shaft (4-2) is vertically mounted on the rotating motor (4-1), the horizontal rod (4-3) is connected to the rotating shaft (4-2) in the middle, the horizontal rod (4-3) is 120 mm long, the trigger electrode I (4-4) and the trigger electrode II (4-6) are both cubes with a side length of 8 mm and are respectively mounted at both ends of the horizontal rod (4-3), and the rotating shaft (4-2), the horizontal rod (4-3), the trigger electrode I (4-4) and the trigger electrode II (4-6) are electrically conductive;The two contacts I (4-5) are identical metal cylinders with their axes along the y direction. The two contacts I (4-5) are spaced 10 mm apart and coaxially arranged. The metal cylinder has a height of 10 mm and a bottom diameter of 10 mm. The axis of the contact I (4-5) is 64 mm away from the axis of the rotation axis (4-2). The two contacts II (4-7) are identical metal bars in the shape of 1 / 6 arcs. The center of the arc is located on the axis of the rotation axis (4-2) and the radius of curvature is 64 mm. m, the two metal strips are spaced 10 mm apart in the y direction and arranged up and down, the two contacts I (4-5) are electrically connected to each other, the two contacts II (4-7) are electrically connected to each other, the rotary motor (4-1) can rotate the horizontal rod (4-3) in the horizontal plane through the rotary shaft (4-2), and the trigger electrode I (4-4) and the trigger electrode II (4-6) can pass through the gap between the two contacts I (4-5) and the gap between the two contacts II (4-7) without contact. ;

[0032] like Figure 4 This is a magnified schematic diagram of the sample chamber. Figure 5 yes Figure 4AA cross-sectional view, the sample chamber (12) comprises a chamber body (12-1), a plane mirror (12-2), a working electrode (12-3), a counter electrode (12-4), a gasket (12-5), a sample (12-6), a transmission window (12-7), a chamber cover (12-8), a reference electrode (12-9), a connector I (12-10) and a connector II (12-11), wherein the plane mirror (12-2), the working electrode (12-3), the counter electrode (12-4), the gasket (12-5), the sample (12-6) and the transmission window (12-7) are all located in the chamber body (12-1); the reference electrode (12-9) is connected to the capacitor (5), the spark switch (4) in sequence by cables. The rotating shaft (4-2), the contact I (4-5) of the spark switch (4), the input end of the power distributor (6), the output end I of the power distributor (6), the transmission line II (10) and the connector II (12-11), the connector I (12-10) and the connector II (12-11) of the sample chamber (12) are respectively connected to the positive electrode and the negative electrode of the constant potential device (17), and the constant potential device (17) is located below the sample chamber (12) in the bracket (11); the chamber (12-1) is a cylindrical barrel with an axis along the y direction, the plane mirror (12-2) is a cylindrical barrel with an axis along the y direction and is located at the bottom of the chamber (12-1), the plane mirror (12-2) has a diameter of 30 mm and is made of polytetrafluoroethylene. The plane mirror (12-2) is made of ethylene material, and a working electrode (12-3) and a counter electrode (12-4) are deposited on the upper surface and side of the plane mirror (12-2), and the working electrode (12-3) and the counter electrode (12-4) are both made of gold and have a thickness of 500 microns; the side of the cavity (12-1) has two through holes, and the connector I (12-10) and the connector II (12-11) can respectively contact the working electrode (12-3) and the counter electrode (12-4) on the side of the plane mirror (12-2) through the two through holes; the gasket (12-5) is made of epoxy resin material and is located on the upper surface of the plane mirror (12-2), and the outer diameter of the gasket (12-5) is 30 mm and the inner diameter is 26 mm. The transmission window (12-7) is located above the gasket (12-5), the diameter of the transmission window (12-7) is 30 mm, the sample (12-6) is placed within the inner diameter of the gasket (12-5), the cavity cover (12-8) is installed above the cavity (12-1), the cavity cover (12-8) can transmit light and can seal the cavity (12-1), the cavity cover (12-8) can press the transmission window (12-7), the gasket (12-5) and the plane mirror (12-2), the cavity cover (12-8) and the transmission window (12-7) both have a through hole in the y direction, and the reference electrode (12-9) can be inserted into the sample (12-6) through the through hole.

[0033] The electrochemical experimental device for spectral measurement comprises a high-voltage direct current power supply (1), a charging resistor (2), a charging line (3), a spark switch (4), a capacitor (5), a power distributor (6), an attenuator (7), a transmission line I (8), an oscilloscope (9), a transmission line II (10), a bracket (11), a sample chamber (12), an optical tester (13), a thermometer (14), a semiconductor refrigerator (15), a heat conduction platform (16) and a constant potentiostat (17), wherein xyz is a three-dimensional space coordinate system, the high-voltage direct current power supply (1) has a positive output terminal and a negative output terminal, and the high-voltage direct current power supply (1) has a positive output terminal and a negative output terminal. The output voltage range of the DC power supply (1) is 1 kV to 2 kV. The power distributor (6) has an input terminal, an output terminal I and an output terminal II. The constant potentiostat (17) has a positive electrode and a negative electrode. The output terminal II of the power distributor (6) is connected to an attenuator (7), a transmission line I (8) and an oscilloscope (9) in sequence via cables. The sample chamber (12), a support (11), a semiconductor refrigerator (15) and a heat conduction platform (16) are connected in sequence from top to bottom. The support (11) is connected to a thermometer (14). The optical tester (13) is located directly above the sample chamber (12). (13) can emit laser and perform spectral analysis on the collected light, wherein the laser includes pump light and detection light; the sample cavity (12) includes a cavity (12-1), a plane mirror (12-2), a working electrode (12-3), a counter electrode (12-4), a gasket (12-5), a sample (12-6), a transmission window (12-7), a cavity cover (12-8), a reference electrode (12-9), a connector I (12-10) and a connector II (12-11), wherein the plane mirror (12-2), the working electrode (12-3), the counter electrode (12-4), the gasket (12-5), The sample (12-6) and the transmission window (12-7) are both located in the cavity (12-1); the connector I (12-10) and the connector II (12-11) of the sample cavity (12) are respectively connected to the positive electrode and the negative electrode of the constant potentiostat (17); the constant potentiostat (17) is located below the sample cavity (12) in the bracket (11); the positive electrode of the output end of the high-voltage direct current power supply (1) is connected to the charging resistor (2), the charging line (3), the contact II (4-7) of the spark switch (4), the rotating shaft (4-2) of the spark switch (4), the capacitor (5) and the negative electrode of the output end of the high-voltage direct current power supply (1) in sequence by a cable;The spark switch (4) comprises a rotary motor (4-1), a rotary shaft (4-2), a horizontal rod (4-3), a trigger electrode I (4-4), two contacts I (4-5), a trigger electrode II (4-6) and two contacts II (4-7), the rotary shaft (4-2) is vertically mounted on the rotary motor (4-1), the horizontal rod (4-3) is connected to the rotary shaft (4-2) in the middle, the horizontal rod (4-3) is 120 mm long, the trigger electrode I (4-4) and the trigger electrode II (4-6) are both cubes with a side length of 8 mm and are respectively mounted at two ends of the horizontal rod (4-3 ... vertically mounted on the rotary motor (4-1), the horizontal rod (4-3) is vertically mounted on the rotary motor (4-1), the horizontal rod (4-3) is vertically mounted on the rotary motor (4-1), the horizontal rod (4-3) is vertically mounted on the rotary motor (4-1), the horizontal rod (4-3) is vertically mounted on the rotary motor (4- -2), the horizontal rod (4-3), the trigger electrode I (4-4) and the trigger electrode II (4-6) are electrically conductive; the two contacts I (4-5) are identical metal cylinders with axes along the y direction, the two contacts I (4-5) are 10 mm apart and coaxially arranged, the metal cylinder is 10 mm high and has a bottom diameter of 10 mm, the axis of the contact I (4-5) is 64 mm away from the axis of the rotation axis (4-2), and the two contacts II (4-7) are identical metal bars in the shape of 1 / 6 arcs, the center of the arcs is located on the axis of the rotation axis (4-2), and the radius of curvature is 64 mm The two metal strips are spaced 10 mm apart in the y direction and arranged vertically, the two contacts I (4-5) are electrically connected to each other, the two contacts II (4-7) are electrically connected to each other, the rotary motor (4-1) can rotate the horizontal rod (4-3) in the horizontal plane through the rotary shaft (4-2), and the trigger electrode I (4-4) and the trigger electrode II (4-6) can pass through the gap between the two contacts I (4-5) and the gap between the two contacts II (4-7) without contact; the cavity (12-1) is a cylindrical barrel with its axis along the y direction, and the plane mirror (12-2) is a cylindrical barrel with its axis along the y direction. The cavity (12-1) is located at the bottom of the cavity (12-1), the plane mirror (12-2) has a diameter of 30 mm and is made of polytetrafluoroethylene material, the upper surface and side surface of the plane mirror (12-2) are deposited with a working electrode (12-3) and a counter electrode (12-4), both of which are made of gold and have a thickness of 500 microns; the side surface of the cavity (12-1) has two through holes, and the connector I (12-10) and the connector II (12-11) can respectively be in close contact with the working electrode (12-3) and the counter electrode (12-4) on the side surface of the plane mirror (12-2) through the two through holes;The gasket (12-5) is made of epoxy resin material and is located on the upper surface of the plane mirror (12-2). The outer diameter of the gasket (12-5) is 30 mm, the inner diameter is 26 mm, and the typical thickness is 5 to 30 μm. The transmission window (12-7) is located above the gasket (12-5). The diameter of the transmission window (12-7) is 30 mm. The sample (12-6) is placed within the inner diameter of the gasket (12-5). The cavity cover (12-8) is installed above the cavity (12-1). The cavity cover (12-8) can transmit light and can seal the cavity (12-1). The cavity cover (12-8) can The transmission window (12-7), the gasket (12-5) and the plane mirror (12-2) are pressed tightly, the cavity cover (12-8) and the transmission window (12-7) both have a through hole in the y direction, the reference electrode (12-9) can be inserted into the sample (12-6) through the through hole, and the reference electrode (12-9) is connected to the capacitor (5), the rotating shaft (4-2) of the spark switch (4), the contact I (4-5) of the spark switch (4), the input end of the power distributor (6), the output end I of the power distributor (6), the transmission line II (10) and the connector II (12-11) in sequence. ;

[0034] Principle of applying high voltage pulse to sample (12-6):

[0035] The spark switch (4) has two spark gaps, which are used for charging and discharging respectively, and can eliminate irregular and unstable pulses generated by charge discharge in the pulse generating circuit. The rotating motor (4-1) of the spark switch (4) drives the trigger electrode I (4-4) and the trigger electrode II (4-6) to rotate in a horizontal plane through a rotating shaft (4-2) and a horizontal rod (4-3), so that the trigger electrode I (4-4) and the trigger electrode II (4-6) alternately pass through the contact I (4-5) and the contact II (4-7) in time, and at the same time, the trigger electrode I (4-4) and the trigger electrode II (4-6) cannot pass through the contact I (4-5) and the contact II (4-7) at the same time, and similarly, the trigger electrode I (4-4) and the trigger electrode II (4-6) cannot pass through the contact II (4-7) and the contact I (4-5) at the same time. When the trigger electrode I (4-4) or the trigger electrode II (4-6) passes through the contact II (4-7), a spark is generated in the gap between the trigger electrode I (4-4) or the trigger electrode II (4-6) and the contact II (4-7), thereby causing the trigger electrode I (4-4) or the trigger electrode II (4-6) to be connected to the contact II (4-7), and the high-voltage direct current power supply (1) charges the capacitor (5); when the trigger electrode I (4-4) or the trigger electrode II (4-6) passes through the contact I (4-5), a spark is generated in the gap between the trigger electrode I (4-4) or the trigger electrode II (4-6) and the contact I (4-5), thereby causing the trigger electrode I (4-4) or the trigger electrode II (4-6) to be connected to the contact I (4-5), and the capacitor (5) discharges the sample (12-6) in the sample chamber (12).

[0036] Principle of electrochemical measurement of sample (12-6):

[0037] The positive electrode and the negative electrode of the constant potentiostat (17) are connected to the working electrode (12-3) and the counter electrode (12-4) respectively through connector I (12-10) and connector II (12-11) to apply an electrochemical potential to the sample (12-6). The sample (12-6) will have different chemical forms under different electrochemical potentials.

[0038] Principle of spectral experimental measurement of sample (12-6):

[0039] The optical tester (13) emits two light pulses, namely, pump light and probe light. The pump light and probe light have different powers, frequencies and durations. The delay time of the probe light relative to the pump light can be adjusted. The pump light emitted by the optical tester (13) sequentially passes through the cavity cover (12-8) and the transmission window (12-7) and is projected onto the sample (12-6) from top to bottom, causing the sample (12-6) to react. The probe light emitted by the optical tester (13) sequentially passes through the cavity cover (12-8) and the transmission window (12-7) and is projected onto the sample (12-6) from top to bottom, causing the sample (12-6) to react. A certain degree of scattering is generated, wherein a portion of the detection light incident on the working electrode (12-3) and the upper surface of the counter electrode (12-4) is reflected to form reflected light, and the reflected light is incident on the sample (12-6) again from bottom to top, wherein a portion of the reflected light passes through the sample (12-6) to form secondary transmitted light, and the secondary transmitted light passes through the transmission window (12-7) and the cavity cover (12-8) in turn and then enters the optical tester (13). By analyzing the characteristics of the secondary transmitted light collected by the optical tester (13), the relevant characteristics of the sample (12-6) can be obtained.

[0040] The laser emitted by the optical tester (13) is incident on the sample (12-6) at an angle of 0.5 degrees to the normal phase of the upper surface of the transmission window (12-7). The advantage is that the light reflected from the upper surface of the transmission window (12-7) and the light after being acted on by the sample (12-6) are spatially separated, thereby avoiding the interference of pump light in the spectrum collected by the optical tester (13).

[0041] The working electrode (12-3) and the counter electrode (12-4) made of gold on the upper surface of the plane mirror (12-2) are used as working electrodes, instead of using a metal grid as the working electrode as in some spectral measurement devices in the prior art. The advantage is that the problem of light scattering can be avoided and the signal-to-noise ratio of the optical signal collected by the optical tester (13) can be increased. In addition, since the light passes through the sample twice, the intensity of the signal collected by the optical tester (13) is doubled, which is very important when the sample amount is small. The device of the present invention only needs a small amount of sample when performing spectral experiments, and the use of thinner samples can reduce the time to reach the electrochemical equilibrium state, which is very important for some rapid redox cycle processes.

[0042] The structural design of the sample chamber (12) can be adapted to samples of different thicknesses by selecting gaskets (12-5) of different thicknesses, and has good air tightness.

[0043] The device of the present invention has a specially designed voltage pulse generating circuit and a compact sample chamber, which can simultaneously study the electrochemical and spectral characteristics of the sample after the sample is subjected to high voltage treatment. The high voltage pulse applied to the sample is regular and stable, and the signal-to-noise ratio of the obtained spectrum is improved.

Claims

1. An electrochemical experimental device for spectral measurement, comprising a high voltage DC power supply (1), a charging resistor (2), a charging line (3), a spark switch (4), a capacitor (5), a power divider (6), an attenuator (7), a transmission line I (8), an oscilloscope (9), a transmission line II (10), a bracket (11), a sample chamber (12), an optical tester (13), a thermometer (14), a semiconductor refrigerator (15), a heat conduction platform (16) and a constant potentiostat (17), wherein xyz is a three-dimensional space coordinate system, and the high voltage DC power supply (1) is a three-dimensional space coordinate system, wherein the high voltage DC power supply (1) is a three-dimensional space coordinate system, wherein the high voltage DC power supply (2) is a three-dimensional space coordinate system, wherein the high voltage DC power supply (3) is a three-dimensional space coordinate system, wherein the high voltage DC power supply (4) is a three-dimensional space coordinate system, wherein the high voltage DC power supply (5) is a three-dimensional space coordinate system, wherein the high voltage DC power supply (6) is a three-dimensional space coordinate system, wherein the high voltage DC power supply (7) is a three-dimensional space coordinate system, wherein the high voltage DC power supply (8 ... The high-voltage DC power supply (1) has a positive output terminal and a negative output terminal, the output voltage range of the high-voltage DC power supply (1) is 1 kV to 2 kV, the power distributor (6) has an input terminal, an output terminal I and an output terminal II, the constant potentiostat (17) has a positive electrode and a negative electrode, the output terminal II of the power distributor (6) is connected to the attenuator (7), the transmission line I (8) and the oscilloscope (9) in sequence by cables, the sample chamber (12), the support (11), the semiconductor refrigerator (15) and the heat conduction platform (16) are connected in sequence from top to bottom, the support (11) is connected to the semiconductor refrigerator (15) and the heat conduction platform (16) in sequence, The rack (11) is connected to a thermometer (14); the optical tester (13) is located directly above the sample cavity (12); the optical tester (13) can emit laser light and perform spectral analysis on the collected light; the laser light includes pump light and detection light; the sample cavity (12) includes a cavity (12-1), a plane mirror (12-2), a working electrode (12-3), a counter electrode (12-4), a gasket (12-5), a sample (12-6), a transmission window (12-7), a cavity cover (12-8), a reference electrode (12-9), and a cavity body (12-1). 2-9), connector I (12-10) and connector II (12-11), the plane mirror (12-2), working electrode (12-3), counter electrode (12-4), gasket (12-5), sample (12-6) and transmission window (12-7) are all located in the cavity (12-1), connector I (12-10) and connector II (12-11) of the sample cavity (12) are respectively connected to the positive electrode and negative electrode of the constant potentiostat (17), and the constant potentiostat (17) is located below the sample cavity (12) in the bracket (11), Its characteristics are: The positive electrode of the output end of the high-voltage direct current power source (1) is connected to the charging resistor (2), the charging line (3), the contact II (4-7) of the spark switch (4), the rotating shaft (4-2) of the spark switch (4), the capacitor (5) and the negative electrode of the output end of the high-voltage direct current power source (1) in sequence by a cable; the spark switch (4) comprises a rotating motor (4-1), a rotating shaft (4-2), a horizontal rod (4-3), a trigger electrode I (4-4), two contacts I (4-5), a trigger electrode II (4-6) and two contacts II (4-7); the rotating shaft (4-2) is vertically mounted on the rotating motor (4-1); the horizontal rod (4-3) is connected to the rotating shaft (4-2) in the middle; the horizontal rod (4-3) ) is 120 mm in length, the trigger electrode I (4-4) and the trigger electrode II (4-6) are both cubes with a side length of 8 mm and are respectively installed at the two ends of the horizontal rod (4-3), and the rotating shaft (4-2), the horizontal rod (4-3), the trigger electrode I (4-4) and the trigger electrode II (4-6) are electrically conductive; the two contacts I (4-5) are identical metal cylinders with axes along the y direction, the two contacts I (4-5) are spaced 10 mm apart and coaxially arranged, the metal cylinder is 10 mm in height and 10 mm in bottom diameter, the axis of the contact I (4-5) is 64 mm away from the axis of the rotating shaft (4-2), and the two contacts II (4-7) are opposite The invention relates to a metal strip having a 1 / 6 arc shape, the center of which is located on the axis of the rotating shaft (4-2) and the radius of curvature is 64 mm, the two metal strips are spaced 10 mm apart in the y direction and arranged in an up-and-down manner, the two contacts I (4-5) are electrically conductive to each other, the two contacts II (4-7) are electrically conductive to each other, the rotating motor (4-1) can rotate the horizontal rod (4-3) in the horizontal plane through the rotating shaft (4-2), and the trigger electrode I (4-4) and the trigger electrode II (4-6) can pass through the gap between the two contacts I (4-5) and the gap between the two contacts II (4-7) without contact; the cavity (12-1) is a cylinder with its axis along the y direction. The plane mirror (12-2) is barrel-shaped, the axis is along the y direction and is located at the bottom of the cavity (12-1), the diameter of the plane mirror (12-2) is 30 mm and is made of polytetrafluoroethylene material, the upper surface and side surface of the plane mirror (12-2) are deposited with a working electrode (12-3) and a counter electrode (12-4), the working electrode (12-3) and the counter electrode (12-4) are both made of gold and have a thickness of 500 microns; the side surface of the cavity (12-1) has two through holes, and the connector I (12-10) and the connector II (12-11) can respectively contact the working electrode (12-3) and the counter electrode (12-4) on the side surface of the plane mirror (12-2) through the two through holes;The gasket (12-5) is made of epoxy resin material and is located on the upper surface of the plane mirror (12-2). The outer diameter of the gasket (12-5) is 30 mm, the inner diameter is 26 mm, and the typical thickness is 5 to 30 μm. The transmission window (12-7) is located above the gasket (12-5). The diameter of the transmission window (12-7) is 30 mm. The sample (12-6) is placed within the inner diameter of the gasket (12-5). The cavity cover (12-8) is installed above the cavity (12-1). The cavity cover (12-8) can transmit light and can seal the cavity (12-1). The cavity cover (12-8) can The transmission window (12-7), the gasket (12-5) and the plane mirror (12-2) are pressed tightly, the cavity cover (12-8) and the transmission window (12-7) both have a through hole in the y direction, the reference electrode (12-9) can be inserted into the sample (12-6) through the through hole, and the reference electrode (12-9) is connected to the capacitor (5), the rotating shaft (4-2) of the spark switch (4), the contact I (4-5) of the spark switch (4), the input end of the power distributor (6), the output end I of the power distributor (6), the transmission line II (10) and the connector II (12-11) in sequence. ;

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