CN212433045U - Flow battery electrode active area detection device - Google Patents
Flow battery electrode active area detection device Download PDFInfo
- Publication number
- CN212433045U CN212433045U CN202021192339.3U CN202021192339U CN212433045U CN 212433045 U CN212433045 U CN 212433045U CN 202021192339 U CN202021192339 U CN 202021192339U CN 212433045 U CN212433045 U CN 212433045U
- Authority
- CN
- China
- Prior art keywords
- electrode
- module
- phase
- optical sensing
- active area
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
- 238000001514 detection method Methods 0.000 title claims abstract description 44
- 230000003287 optical effect Effects 0.000 claims abstract description 70
- 230000008859 change Effects 0.000 claims abstract description 45
- 238000003487 electrochemical reaction Methods 0.000 claims abstract description 28
- 239000003792 electrolyte Substances 0.000 claims abstract description 25
- 238000002484 cyclic voltammetry Methods 0.000 claims description 30
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims description 10
- 229910002804 graphite Inorganic materials 0.000 claims description 10
- 239000010439 graphite Substances 0.000 claims description 10
- 239000007772 electrode material Substances 0.000 claims description 8
- 230000003595 spectral effect Effects 0.000 claims description 8
- 238000004832 voltammetry Methods 0.000 claims description 7
- BASFCYQUMIYNBI-UHFFFAOYSA-N platinum Chemical compound [Pt] BASFCYQUMIYNBI-UHFFFAOYSA-N 0.000 claims description 6
- ZOMNIUBKTOKEHS-UHFFFAOYSA-L dimercury dichloride Chemical class Cl[Hg][Hg]Cl ZOMNIUBKTOKEHS-UHFFFAOYSA-L 0.000 claims description 5
- 238000012360 testing method Methods 0.000 claims description 5
- 239000013307 optical fiber Substances 0.000 claims description 3
- 229910052720 vanadium Inorganic materials 0.000 claims description 2
- 238000000034 method Methods 0.000 description 36
- 230000008569 process Effects 0.000 description 18
- 230000003647 oxidation Effects 0.000 description 12
- 238000007254 oxidation reaction Methods 0.000 description 12
- 238000011065 in-situ storage Methods 0.000 description 9
- 230000009467 reduction Effects 0.000 description 8
- 238000006722 reduction reaction Methods 0.000 description 8
- 238000002474 experimental method Methods 0.000 description 7
- 238000006479 redox reaction Methods 0.000 description 7
- 230000035945 sensitivity Effects 0.000 description 6
- 238000001228 spectrum Methods 0.000 description 6
- 238000010586 diagram Methods 0.000 description 5
- 238000012512 characterization method Methods 0.000 description 4
- 238000006243 chemical reaction Methods 0.000 description 4
- 239000010408 film Substances 0.000 description 4
- 230000004048 modification Effects 0.000 description 4
- 238000012986 modification Methods 0.000 description 4
- 230000007547 defect Effects 0.000 description 3
- 230000000694 effects Effects 0.000 description 3
- 238000005516 engineering process Methods 0.000 description 3
- 239000000463 material Substances 0.000 description 3
- 238000004438 BET method Methods 0.000 description 2
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 description 2
- 238000004630 atomic force microscopy Methods 0.000 description 2
- 230000002902 bimodal effect Effects 0.000 description 2
- 239000003054 catalyst Substances 0.000 description 2
- 230000005518 electrochemistry Effects 0.000 description 2
- 238000001493 electron microscopy Methods 0.000 description 2
- 238000004502 linear sweep voltammetry Methods 0.000 description 2
- 230000004044 response Effects 0.000 description 2
- 206010024769 Local reaction Diseases 0.000 description 1
- 239000013543 active substance Substances 0.000 description 1
- 239000002390 adhesive tape Substances 0.000 description 1
- 239000012491 analyte Substances 0.000 description 1
- 239000003638 chemical reducing agent Substances 0.000 description 1
- 230000008878 coupling Effects 0.000 description 1
- 238000010168 coupling process Methods 0.000 description 1
- 238000005859 coupling reaction Methods 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 238000009792 diffusion process Methods 0.000 description 1
- 239000010411 electrocatalyst Substances 0.000 description 1
- 238000004146 energy storage Methods 0.000 description 1
- 239000000835 fiber Substances 0.000 description 1
- 238000003384 imaging method Methods 0.000 description 1
- 150000002500 ions Chemical class 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 238000000399 optical microscopy Methods 0.000 description 1
- 230000035515 penetration Effects 0.000 description 1
- 238000011897 real-time detection Methods 0.000 description 1
- 238000011946 reduction process Methods 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 230000000630 rising effect Effects 0.000 description 1
- 238000007086 side reaction Methods 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 238000001179 sorption measurement Methods 0.000 description 1
- 239000010409 thin film Substances 0.000 description 1
- 230000001131 transforming effect Effects 0.000 description 1
- 238000001075 voltammogram Methods 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
Images
Landscapes
- Investigating Or Analysing Materials By Optical Means (AREA)
Abstract
The utility model relates to the technical field of detection, a flow battery electrode active area detection device is disclosed, including the electrode that awaits measuring, still include electric potential scanning system and optical sensing system, electric potential scanning system includes three electrode system modules, and optical sensing system includes incident light module, optical sensing module and phase place mediation module; the incident light module is used for providing 45-degree linearly polarized light, the optical sensing module is used for measuring the change of the refractive index of electrolyte at a sensing interface contacted with an electrode to be measured, and the phase demodulation module is used for simultaneously obtaining the phase change information of reflected light at the sensing interface. The utility model discloses combined potential scanning system and optical sensor, obtained electrode electrochemical reaction's whole electric current and current density respectively, given the active area who actually participates in electrochemical reaction, provided a sign electrode and participated in electrochemical reaction active area's technical tool.
Description
Technical Field
The utility model relates to a detect technical field, especially relate to a flow battery electrode active area detection device.
Background
Energy issues have driven the development of clean energy and energy storage technologies, including water splitting and flow batteries. The performance improvements of these techniques relate to improvements in catalyst and electrode activity, etc. The electrocatalyst is loaded on the surface of the electrode, and the surface state of the electrode is changed, so that the potential and the reaction rate of the reaction are changed, and the electrode can select electrochemical reaction. Among them, the catalyst active area and the electrode active area are one of important factors affecting the electrochemical reaction thereof.
According to the literature (chem.soc.rev.,48,2518(2019)), the main methods for characterizing the active area of the electrode are the redox reaction method, the electric double layer capacitance method, the atomic force microscopy, the electron microscopy, the BET method, and the like. The redox reaction method is mainly to obtain all transferred charges divided by the transferred charges of a single active site according to the area of the cyclic voltammogram to give the active area. The method has the defects that the number of transferred charges of the active site of the electrode material is unknown experimentally, and the area integral baseline is difficult to determine. The electric double layer capacitance method is to divide the electric double layer capacitance by the specific capacitance to obtain the active area. The electric double layer capacitance measured by the method can change along with the electrode potential and the electrode composition, and is influenced by side reaction, so that the measured active area has consistency. The atomic force microscopy gives the active area of the electrode by measuring the roughness of the electrode and combining the geometric area obtained by optical microscopy, and the method is only suitable for thin film materials with smooth surfaces. Electron microscopy determines the surface area of an analyte by measuring its diameter and idealized its shape. The method has the defects that the difference between the physical ideal shape to be measured and the actual shape causes errors of measurement results and the like. The BET method, which is currently the best choice for obtaining the active area, is to obtain the surface area of a material by means of physical adsorption of gas molecules on the solid surface of the material to be measured. It has the problems that the measured surface area is not equal to the active area actually participating in the electrochemical reaction, and the like. Therefore, these methods all have their own disadvantages, and there is a need for a more efficient and simple method for in situ characterization of the active area of an electrode.
The evanescent wave optical detection method is widely applied to the field of biomedicine due to the characteristics of high sensitivity, high resolution, in-situ nondestructive detection and the like, can detect the refractive index change at an interface in real time, and can measure the current density of electrochemical reaction. The patent of 'a method and a device for detecting the local reaction activity of a flow battery electrode on line' (application number 201811617909.6) and the patent of 'a method and a device for detecting the current density distribution of the flow battery electrode in situ' (application number 201910060777.X) are applied, and the method and the device respectively use a surface plasma resonance technology to characterize the electrode activity and a total reflection imaging technology to detect the current density distribution in the battery operation process in situ. The utility model discloses then utilize the phase type optical sensor of higher sensitivity to combine electrochemical workstation, provide flow battery electrode active area detection device, provide the active area who actually participates in electrochemical reaction.
The utility model discloses use redox flow battery electrode material graphite felt to select reflection-type phase type optical sensor as an example and realize the measuring to electrode cyclic voltammetry in-process electrolyte refracting index, and then obtain electrode current density, combine the electric current that the electrochemistry workstation obtained, obtain the active area of electrode at last. The utility model provides a sign electrode participates in electrochemical reaction active area's technical tool.
SUMMERY OF THE UTILITY MODEL
To above-mentioned prior art's defect, the utility model provides an use redox flow battery electrode for example measure electrode participate in electrochemical reaction active area's normal position detection device, adopt electric potential scanning system and optical sensing system to carry out normal position detection to electrode electrochemical reaction simultaneously, optical sensing system changes the current density who calculates the electrode through the optical signal who gathers electrolyte refractive index and arouse, electric potential scanning system obtains the electrode current, and the electrode current is divided by current density and is obtained electrode active area.
The utility model provides a flow battery electrode active area detection device, including the electrode of awaiting measuring, still include electric potential scanning system and optical sensing system, electric potential scanning system includes three electrode system modules, optical sensing system includes incident light module, optical sensing module and phase place mediation module; the optical sensing module is used for measuring the change of the refractive index of electrolyte at a sensing interface contacted with an electrode to be measured, and the phase demodulation module is used for simultaneously obtaining the phase change information of reflected light at the sensing interface.
Furthermore, the detection device also comprises an electrochemical workstation for carrying out electrochemical reaction by the three-electrode system module, a computer for displaying the cyclic voltammetry curve obtained by the electrochemical workstation, and a computer for receiving the spectral image formed by the phase modulation module.
Further, in the above detection apparatus, the optical sensing system is a prism-coupled reflective phase-type optical sensor, the optical sensing module is a prism, and an interface of the prism is in contact with the electrode to be detected.
Further, in the detection device, the incident light module is 45 ° linearly polarized light with a wavelength ranging from 800nm to 890nm, and the components of the incident light module are equivalent horizontally polarized light and vertically polarized light.
Further, according to the detection device, the incident light module (1) comprises a super-radiation light-emitting diode (SLD), a collimating lens, a band-pass filter and a first polarizing film, light emitted by the super-radiation light-emitting diode (SLD) is guided out by an optical fiber and passes through the collimating lens, the band-pass filter and the first polarizing film to form 45-degree linearly polarized light, the light is incident to the optical sensing module at an angle larger than a total reflection angle, the optical sensing module is in total reflection with a contact interface of an electrode to be detected, and the phase demodulation module is used for acquiring phase difference change of horizontal and vertical polarized light.
Further, in the above detection apparatus, the phase demodulation module includes a phase retarder, a second polarizer, a converging lens, and a spectrometer, the second polarizer and the first polarizer are in an orthogonal state, and the spectrometer displays the detection signal on a computer receiving the spectral image.
Further, in the detection device, the three-electrode system module comprises a working electrode, a counter electrode and a reference electrode, the working electrode is a platinum wire inserted into the electrode to be detected, the counter electrode is a graphite rod, and the reference electrode is a saturated calomel electrode.
Further, in the detection device, the electrochemical workstation drives the three-electrode system module to perform an electrochemical reaction, and a cyclic voltammetry curve obtained by the electrochemical workstation is displayed on a computer receiving the voltammetry curve.
Furthermore, the detection device also comprises a container, wherein electrolyte is filled in the container, and the electrolyte soaks the electrode to be detected.
Further, in the detection device, the flow battery to be detected is an all-vanadium flow battery, and the electrode material of the electrode to be detected is graphite felt.
The utility model has the advantages that: the utility model provides a redox flow battery electrode active area detection device utilizes the phase type optical sensor of higher sensitivity to combine electrochemical workstation to carry out the normal position to electrode active area and detect, and is easy and simple to handle, gives the active area who actually participates in electrochemical reaction, provides a sign electrode and participates in electrochemical reaction active area's technological tool.
Drawings
Fig. 1 is a schematic diagram of a phase-type optical sensor for electrode active area detection and a three-electrode system module, wherein 1, an incident light module; 2. an optical sensing module; 3. the phase adjusting module, 4, the three-electrode system module;
FIG. 2 is a schematic diagram of a phase type optical sensor versus flow cell electrode active area in situ detection system in a cyclic voltammetry process or a linear sweep voltammetry process; 11, a superluminescent diode SLD, 12, a collimating lens, 13, a band-pass filter, 14, a first polarizing film, 15, a prism, 16, a phase retarder, 17, a second polarizing film, 18, a converging lens, 19 and a spectrometer; 21. the method comprises the following steps that (1) an electrode to be tested 22, a platinum wire 23, a graphite rod 24, a saturated calomel electrode 25, a container 26, an electrochemical workstation 31, a computer for receiving spectrum images and a computer for receiving voltammetry curves 32 are respectively connected;
FIG. 3 is a flow chart showing the details of the in-situ detection method of the active area of the electrode material participating in the electrochemical reaction according to the detection device of the present invention;
FIG. 4 is a graph of the results of a uniform tunable electrode calibration experiment;
fig. 5 is a process diagram of an optical sensor detecting an active area of an electrode material participating in an electrochemical reaction during cyclic voltammetry.
Detailed Description
The following detailed description of the present invention is provided in conjunction with the accompanying drawings, but it should be understood that the scope of the present invention is not limited by the following detailed description.
It should be noted that, rely on the utility model provides a flow battery electrode active area detection device specifically is for carrying out cyclic voltammetry test process at electrochemistry workstation drive electrode, utilizes optical sensor to participate in the redox reaction process change on the electrode and carry out real-time detection. The process calculates the current density of the electrode by collecting the optical signal change caused by the electrolyte refractive index change. The electrochemical workstation can obtain the current, so that the active area of the electrode can be obtained by dividing the electrochemical workstation and the electrochemical workstation. Specifically, taking a prism-coupled reflective phase-type optical sensor as an example, when linearly polarized light is incident on a sensing interface where a prism is in contact with an electrode at an angle larger than a total reflection angle, there is a difference in phase change between p-polarized light and s-polarized light at the interface. Meanwhile, the refractive index of the prism is fixed, so that the phase change quantity of the p-polarized light and the s-polarized light has a quantitative relation with the refractive index of the electrolyte near the electrode to be measured, and a high-sensitivity dynamic range exists in a certain refractive index range. The utility model discloses an utilize and adjust optical sensor to this dynamic range and realize detecting electrode electrochemical reaction.
The principle of the device is that the oxidation-reduction reaction of an electrode to be detected in a three-electrode system in a cyclic voltammetry process is taken as an example to obtain the active area of the electrode. The electrochemical reaction of the electrode can cause the concentration of active ions with different valence states in the electrolyte to change, so that the refractive index at the interface is changed, and finally the phase change of the reflected light is reflected. The incident light is considered to be linearly polarized light with a certain wavelength range, phase difference is generated on a sensing interface, and meanwhile, the reflection spectrum is in a double-peak shape under the condition of meeting the high-sensitivity dynamic range. Thus the phase change is measured by the change in the center wavelength of the spectral double peak. Therefore, the relation between the change of the interface refractive index and the change of the central wavelength is constructed, and the sensitivity of the system can be reflected. Next, similarly to the literature (Science 327,1363(2010)), the center wavelength of the spectrum of the available phase-type optical sensor and the current density satisfy the following relationship:
The device adopts a total reflection type light path system coupled by a triangular prism, and realizes the in-situ detection of the active area of the electrode by directly contacting and coupling the triangular prism in the system and the electrode to be detected. And (3) carrying out cyclic voltammetry on the electrode by virtue of an electrochemical workstation to obtain a cyclic voltammetry curve, wherein the ordinate of the cyclic voltammetry curve represents the current of the whole electrode. Meanwhile, the change of the valence state of the active substance in the electrolyte on the electrode causes the change of the refractive index, and the change of the central wavelength of the detection signal of the optical sensor is reflected. The current density can be obtained from the above-obtained relationship between the change in the central wavelength signal and the current density. The active area of the electrode is thus obtained by dividing the overall current obtained at the electrochemical workstation by the current density obtained at the optical sensor.
The invention will be further described with reference to the accompanying drawings and a preferred embodiment.
FIG. 1 is an example of a block diagram of a counter electrode active area characterization module for an optical sensor and three electrode system. As shown in FIG. 1, the characterization system is composed of four modules, and the incident light module 1 is 45-degree linearly polarized light with the wavelength ranging from 800nm to 890nm, and the components of the incident light module are equivalent horizontally polarized light and vertically polarized light. The optical sensing module 2 is a high refractive index equilateral prism, and one interface of the optical sensing module is in contact with the electrode to be measured. The change of the refractive index of the electrolyte at the contact sensing interface with the electrode to be measured (graphite felt) is measured by obtaining the phase change of the reflected light behind the high-refractive-index triangular prism. The phase demodulation module 3 simultaneously obtains the reflected light phase change information of the sensing interface, and the central wavelength change of the spectrum curve is collected by the spectrometer to reflect the phase change amount. And obtaining the refractive index change of the electrolyte at the sensing interface according to the quantitative relation between the phase change and the refractive index, and further performing deconvolution calculation to obtain the current density. The three-electrode system module 4 mainly performs cyclic voltammetry on an electrode to be tested which is soaked with electrolyte through an electrochemical workstation, researches the change of the refractive index of the electrolyte at the electrode in the cyclic voltammetry process due to the oxidation-reduction reaction of the electrolyte, and obtains the current density of the electrode at the position through calculation.
Fig. 3 is a flow chart of the main implementation of the detection of the electrode active area depending on the device of the present invention. For the electrode to be detected, a platinum wire is inserted into the electrode to be detected to serve as a working electrode in a three-electrode system, the counter electrode is a graphite rod, and the reference electrode is a saturated calomel electrode. Based on a three-electrode system, an electrochemical workstation is utilized to soak electrolyte (0.1 MVO)2+And 2M H2SO4) The working electrode of (2) is scanned at a rate of 1mV s within a voltage window of 0.5V to 1.2V-1And performing cyclic voltammetry to obtain a cyclic voltammetry curve, and further obtain oxidation or reduction peak current. In the cyclic voltammetry process, an optical response signal is collected by using a reflection type optical sensor, so that the real-time refractive index change of the electrolyte is obtained, and a corresponding cyclic voltammetry curve is obtained by means of the quantitative relation between the refractive index and the current density. The relative current density is obtained at this time.
And performing linear scanning voltammetry test on the uniform adjustable electrode at different potential scanning rates, and dividing the obtained current by the reaction area to obtain the electrochemical current density. Meanwhile, the optical sensor can also obtain a linear scanning voltammetry curve, and the relative current density under different potential scanning rates can be obtained. Thus, the current density obtained by the electrochemical workstation and the relative current density obtained by the optical sensor can be combined to obtain the relation between the two. The calibration experiment thus allows the optical sensor to obtain a current density having physical units.
And for the electrode to be measured, obtaining the current density with a physical unit by using the relational expression obtained by the calibration experiment, and further determining the current density of an oxidation or reduction peak. And finally, dividing the peak current obtained by the electrochemical workstation by the peak current density obtained by the optical sensor to obtain the active area of the electrode material to be detected participating in the electrochemical reaction, thereby realizing the purpose of providing in-situ characterization of the active area for electrode modification.
Specifically, the active area detection method using the flow battery electrode active area detection device of the embodiment includes the following steps:
firstly, an electrode to be measured is transferred into a three-electrode system module as a working electrode and is immersed by electrolyte, so that the electrode is in close contact with a triangular prism, and then the module is assembled into a light path of a sensor;
debugging the reflective phase type optical sensor to a total reflection state, enabling the state of an optical system to be in a dynamic range with the highest sensitivity, and simultaneously recording an initial optical signal of the sensor;
and thirdly, performing cyclic voltammetry on the electrode immersed in the electrolyte by virtue of an electrochemical workstation to obtain a cyclic voltammetry curve, and extracting oxidation or reduction peak current. And meanwhile, a reflected light signal which changes along with time is collected by the phase type optical sensor. Calculating a change curve of the center wavelength along with time according to the reflected light signals;
fourthly, converting the obtained change curve of the central wavelength along with time into a relative current density change curve by utilizing the relation between the central wavelength and the current density, and extracting the relative value of the current density of an oxidation peak or a reduction peak;
and fifthly, determining the relation between the current density obtained by the electrochemical workstation and the relative current density obtained by the optical sensor by performing cyclic voltammetry on the uniform and adjustable electrode with the known area under different potential scanning rates.
And sixthly, acquiring the absolute value of the current density of the electrode to be measured acquired by the optical sensor in the cyclic voltammetry process according to the relation, so that the oxidation or reduction peak current density with a physical unit can be obtained.
And seventhly, dividing the oxidation or reduction peak current of the electrode to be detected obtained by the electrochemical workstation by the optical sensor to obtain the corresponding oxidation or reduction peak current density with a physical unit, so that the active area of the electrode to be detected can be obtained.
FIG. 2 is an example of a system in which the counter electrode of the device takes part in the in-situ detection of the active area of the electrochemical reaction in the cyclic voltammetry process by using a phase optical sensor. As shown in fig. 2, in the incident light module 1, the light emitted from the superluminescent diode SLD11 is guided out by an optical fiber, passes through the collimator lens 12, the band pass filter 13, and the first polarizing plate 14, and then forms 45 ° linearly polarized light, and enters the optical sensor module (the triangular prism 15 having a refractive index of 1.75) at an angle larger than the total reflection angle. After the prism 15 and the contact interface of the electrode 21 to be measured are totally reflected, the phase demodulation module 3 acquires the phase difference change of the horizontal polarized light and the vertical polarized light. The phase demodulation block 3 includes a phase retarder 16, a second polarizer 17, a converging lens 18, and a spectrometer 19. Wherein the phase retarder 16 is adjusted such that the system is in the most sensitive dynamic range. The second polarizer 17 is in a nearly orthogonal state to the first polarizer 14 so that the signal detected by the spectrometer 19 appears on the computer 31 receiving the spectral image, indicating a double peak condition. For the three-electrode system module 4, the platinum wire 22 is inserted into the electrode 21 to be measured to serve as a working electrode, the graphite rod 23 serves as a counter electrode, and the saturated calomel electrode 24 serves as a reference electrode. The container 25 is filled with an electrolyte (0.1M VO)2+And 2M H2SO4) So that it penetrates the electrode to be measured 21. The electrochemical workstation 26 drives the three-electrode system to perform electrochemical reaction, and the valence state change of the electrolyte changes the refractive index of the electrolyte, so that the phase of the polarized light is changedAnd (4) transforming. The computer 32 receiving the voltammograms displays the cyclic voltammograms obtained at the electrochemical workstation. At this time, the response signal of the optical sensor is a change of two peaks, one rising and one falling. The refractive index change of the interface is obtained by calculating the change in the center wavelength thereof. Assuming that nF/b is 1, the relative current density is calculated by deconvolution. In order to obtain the absolute value of the current density having the physical quantity, a calibration experiment needs to be performed.
FIG. 4 is a graph of the results of a calibration experiment. By scanning the uniform adjustable electrode at different potential scanning rates (2mV s)-1、4mV s-1、6mV s-1、8mV s-1And 10mV s-1) A linear sweep voltammetry test was performed. Wherein, as shown in fig. 4(a), the side of the uniform adjustable electrode contacting the triangular prism is not sticky with tape, and is used as the only reaction interface with known area. And the other surfaces are all stuck with adhesive tapes and cannot participate in electrochemical reaction. The current obtained by the electrochemical workstation was then divided by the known area to obtain the current density at different potential scan rates, as shown in fig. 4 (b). Meanwhile, fig. 4(c) shows that the optical sensor obtains a corresponding relative current density. Obtaining oxidation peak currents i.e. i at different potential scanning rates by respectively taking two systemspa(EW)And ipa(OS)And is shown in fig. 4 (d). The calibration experiment allows the optical sensor to obtain a current density with physical units by giving a linear relationship between the current density obtained by the electrochemical workstation and the relative current density obtained by the optical sensor by means of a linear fit.
FIG. 5 is a schematic diagram of the process of detecting the active area of the electrode material participating in the electrochemical reaction in the cyclic voltammetry process by the optical sensor. Fig. 5(a) shows cyclic voltammograms of the electrodes obtained at the electrochemical workstation. Taking a graphite felt with interwoven fibers as an electrode as an example, the active area of the electrode is unknown, the current value obtained by an electrochemical workstation is taken as the oxidation peak current Ipa. Meanwhile, the detection signal obtained by the phase-type optical sensor is a bimodal spectrum as shown by a solid line in fig. 5 (b). In the cyclic voltammetry process, the change of the valence state of the electrolyte caused by the oxidation-reduction reaction process causes the change of the refractive index, so that the light intensity of the double-peak detection signal appears in a rise-rise manner shown by a dotted lineThe change in drop. And calculating the central wavelength of the bimodal spectrum as a detection index. Fig. 5(c) is a graph showing the change of the center wavelength with time. The oxidation process causes the center wavelength to drop sharply when the potential reaches the oxidation potential and the reduction process causes the center wavelength to rise sharply to the initial state when the potential reaches the reduction potential throughout the cyclic voltammetry process. As shown in fig. 5(d), the cyclic voltammogram of the optical sensor was obtained by deconvolution calculation with the use of a linear relationship of a calibration experiment. The sensor is a reflection-type optical sensing structure (penetration depth of evanescent wave is hundreds of nanometers), and current density with physical unit is obtained, and oxidation peak current density is taken as ipa. So that the active area participating in the electrochemical reaction is Ipa/ipa。
It will be apparent to those skilled in the art that various changes and modifications may be made without departing from the spirit and scope of the invention. Thus, if such modifications and variations of the present invention fall within the scope of the claims and their equivalents, the present invention is also intended to include such modifications and variations.
Claims (10)
1. The device for detecting the active area of the electrode of the flow battery is characterized by comprising an electrode (21) to be detected, a potential scanning system and an optical sensing system, wherein the potential scanning system comprises a three-electrode system module (4), and the optical sensing system comprises an incident light module (1), an optical sensing module (2) and a phase adjusting module (3); the light source device comprises an incident light module (1), an optical sensing module (2) and a phase modulation module (3), wherein the incident light module (1) is used for providing 45-degree linearly polarized light, the optical sensing module (2) is used for measuring the refractive index change of electrolyte at a sensing interface contacted with an electrode (21) to be measured, and the phase modulation module (3) is used for simultaneously obtaining the reflected light phase change information of the sensing interface.
2. The detection device according to claim 1, further comprising an electrochemical workstation (26), wherein the electrochemical workstation (26) is used for driving the three-electrode system module (4) to perform electrochemical reaction, a computer (32) for receiving voltammetry curves, the computer (32) for receiving voltammetry curves is used for displaying cyclic voltammetry curves obtained by the electrochemical workstation (26), and a computer (31) for receiving spectral images, and the computer (31) for receiving spectral images is used for receiving the spectral images formed by the phase modulation module (3).
3. A testing device according to claim 2, wherein the optical sensing system is a triple prism coupled reflective phase type optical sensor, the optical sensing module (2) is a triple prism (15), and one interface of the triple prism (15) is in contact with the electrode (21) to be tested.
4. The detection device according to claim 2, characterized in that the incident light module (1) is 45 ° linearly polarized light with a wavelength range of 800nm to 890nm, the components of which are equivalent horizontally polarized light and vertically polarized light.
5. The detection device according to claim 2, wherein the incident light module (1) comprises a superluminescent light emitting diode (SLD) (11), a collimating lens (12), a band pass filter (13) and a first polarizing plate (14), light emitted by the superluminescent light emitting diode (SLD) (11) is guided out by an optical fiber, forms 45-degree linearly polarized light after passing through the collimating lens (12), the band pass filter (13) and the first polarizing plate (14), and is incident on the optical sensing module (2) at an angle larger than a total reflection angle, the optical sensing module (2) and the electrode (21) to be detected are in total reflection at a contact interface, and the phase adjusting module (3) is used for acquiring phase difference changes of horizontal and vertical polarized light.
6. A detection arrangement as claimed in claim 2, characterized in that the phase-adjusting module (3) comprises a phase retarder (16), a second polarizer (17), a converging lens (18) and a spectrometer (19), the second polarizer (17) being orthogonal to the first polarizer (14), the spectrometer (19) displaying the detection signal on a computer (31) receiving the spectral image.
7. The detection device according to claim 2, wherein the three-electrode system module (4) comprises a working electrode, a counter electrode and a reference electrode, wherein the working electrode is a platinum wire (22) inserted into the electrode to be detected (21), the counter electrode is a graphite rod (23), and the reference electrode is a saturated calomel electrode (24).
8. The detection device according to claim 7, wherein the electrochemical workstation (26) drives the three-electrode system module (4) to perform electrochemical reaction, and the cyclic voltammetry curve obtained by the electrochemical workstation (26) is displayed on a computer (32) for receiving the voltammetry curve.
9. The testing device according to claim 2, characterized in that it further comprises a container (25), said container (25) containing an electrolyte, which impregnates the electrode (21) to be tested.
10. The detection device according to claim 2, wherein the flow battery to be detected is an all-vanadium flow battery, and the electrode material of the electrode (21) to be detected is graphite felt.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202021192339.3U CN212433045U (en) | 2020-06-24 | 2020-06-24 | Flow battery electrode active area detection device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202021192339.3U CN212433045U (en) | 2020-06-24 | 2020-06-24 | Flow battery electrode active area detection device |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN212433045U true CN212433045U (en) | 2021-01-29 |
Family
ID=74281961
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202021192339.3U Active CN212433045U (en) | 2020-06-24 | 2020-06-24 | Flow battery electrode active area detection device |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN212433045U (en) |
-
2020
- 2020-06-24 CN CN202021192339.3U patent/CN212433045U/en active Active
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN112903539B (en) | Imaging detection device and method for diffusion coefficient of electrolyte of flow battery | |
| EP3779483A1 (en) | Energy storage device charging state fiber online monitoring system and method | |
| CN106198453B (en) | A kind of online test method and device of the chief and vice reaction ratio of all-vanadium flow battery | |
| CN105388127A (en) | Online detecting method and system for concentration of all ions of all-vanadium redox flow battery | |
| CN111638259A (en) | Method and device for detecting active area of electrode of flow battery | |
| CN110133066A (en) | Electrochemistry pdp optical fiber heavy metal detection system and method | |
| CN101915750A (en) | Biomolecule interaction detection method and system based on SPR interference imaging | |
| CN103759675B (en) | A kind of synchronization detecting method for optical element aspheric surface micro structure | |
| CN109856142B (en) | Device and method for observing behavior of bubbles on surface of electrode | |
| Zhang et al. | An electrochemical surface plasmon resonance imaging system targeting cell analysis | |
| CN109724947B (en) | Online detection method and device for electrode local reaction activity of flow battery | |
| CN108169428A (en) | A kind of formaldehyde gas, humidity and temperature integrated monitor equipment | |
| CN102621078B (en) | Method and device for detecting charging state of vanadium redox battery | |
| CN103424363A (en) | Non-rotary optical rotation solution gauge and method for measuring specific rotation of optical rotation solution through gauge | |
| CN105004781A (en) | Dopamine detecting method based on paper-base electrochemistry device | |
| CN212433045U (en) | Flow battery electrode active area detection device | |
| CN110376261A (en) | A kind of electrochemistry imaging system and method based on the adjustable light scatter properties of graphene | |
| CN202709996U (en) | Device capable of measuring film thickness accurately | |
| CN104020205B (en) | The imprinted polymer membrane electrode of parachloroanilinum, its preparation method and application process | |
| CN208060387U (en) | A kind of multi-functional formaldehyde gas real-time monitoring device | |
| Li et al. | Interferometric measurement of depletion layer structure and voltammetric data in concentrated organic redox solutions | |
| TWI418783B (en) | A method for detecting the concentration of an analyte in a solution and an anesthetic sensor | |
| Lingane et al. | Electrochemical Integrator for Coulometric Analysis | |
| CN207742110U (en) | Non-contact type monitor for high-temperature gas dissolved in ocean | |
| CN111208188A (en) | Transparent electrode potential real-time monitoring device and method based on oblique incident light reflection difference method |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| GR01 | Patent grant | ||
| GR01 | Patent grant |