CN118209612A - Planar optical waveguide in-situ monitoring device and monitoring method for electrocatalytic hydrogen production - Google Patents

Abstract

The invention provides a planar optical waveguide in-situ monitoring device for electrocatalytic hydrogen production and a monitoring method thereof, wherein the planar optical waveguide in-situ monitoring device comprises a broadband light source, an in-situ electrolytic cell, a loss mode resonance sensor, an electrochemical workstation and a spectrometer, wherein the broadband light source, the loss mode resonance sensor and the spectrometer are mutually connected through an optical fiber transmission module; the invention analyzes the influence of the change of the electrocatalytic hydrolysis hydrogen production reaction medium and the dynamic behavior of bubbles generated on the surface of the electrocatalytic film on the catalytic hydrogen production efficiency by monitoring the change of the electrocatalytic hydrolysis hydrogen production reaction medium in real time, and solves the technical problem of difficult in-situ monitoring of the electrocatalytic hydrogen production process in the prior art.

Description

A planar optical waveguide in-situ monitoring device for electrocatalytic hydrogen production and a monitoring method thereof

Technical Field

The present invention relates to the field of electrocatalytic characterization, and in particular to a planar optical waveguide in-situ monitoring device for electrocatalytic hydrogen production and a monitoring method thereof.

Background technique

Hydrogen energy is an ideal green and clean energy source, and the production of hydrogen is closely related to catalytic reactions. In-depth research on the catalytic process can promote the synthesis of efficient catalysts and the optimization of catalytic reaction systems. In recent years, the research on "catalysis and surface interface chemistry" has paid more and more attention to the "surface interface", and in-situ measurement and quantitative analysis of the adsorption, activation, reaction, changes in chemical molecules and mass transfer at the catalyst surface interface has become an indispensable part. However, in the hydrogen production process, such as water electrolysis and photocatalysis, the catalytic environment and the physical and chemical processes of the surface interface are very complex, and it is difficult to accurately analyze the entire process, especially the microscopic process of the surface interface. Therefore, the development of advanced methods for in-situ and real-time online characterization of the surface is of great theoretical and practical significance for understanding complex processes and the relationship between the surface and the catalyst.

With the continuous development of multiphase electrocatalytic hydrogen production technology, its mechanism research has gradually deepened. Researchers use some methods (such as electrochemical detection, mass spectrometry, chromatography, electron microscopy, etc.) to examine the physical and chemical changes of the catalyst surface interface. By studying the surface and interface reaction process, the key factors and microscopic mechanisms that affect its efficiency are revealed. This type of research has become a hot spot and difficulty in the field of interfacial catalysis today. Clarifying the three-phase surface and interface kinetics and microscopic mechanisms in the electrocatalytic hydrogen production system and revealing the structure-activity relationship of the catalytic material are the key to further improving its hydrogen production efficiency, which is crucial to the development of the hydrogen production industry. However, various complex processes related to gas evolution will produce related electrical signals, so their effects should be determined separately. In particular, changes in the electrolysis environment will adjust the performance of the electrode and cause misjudgment.

In recent years, the dynamics of bubble evolution during electrolytic gas production has been studied by atomic force microscopy, transmission electron microscopy, dark field microscopy, high-speed microscopy photography and particle image processing, especially the evolution of single bubbles. However, bulky, inefficient and costly equipment is usually used. In addition, ex situ detection leads to large measurement errors and is heavily dependent on the resolution and response speed of the equipment itself. In addition, in industrial production, the evolution of bubbles is very fast, which brings great difficulties to real-time monitoring.

Summary of the invention

The purpose of the present invention is to provide a planar optical waveguide in-situ monitoring device for electrocatalytic hydrogen production and a monitoring method thereof, which are used to solve the technical problem of the difficulty in in-situ monitoring of the electrocatalytic hydrogen production process in the prior art. In order to solve the above technical problems, the present invention first provides a planar optical waveguide in-situ monitoring device for electrocatalytic hydrogen production, including a broadband light source, an in-situ electrolytic cell, a loss mode resonance sensor, an electrochemical workstation and a spectrometer, wherein the broadband light source, the loss mode resonance sensor and the spectrometer are interconnected through an optical fiber transmission module, the loss mode resonance sensor is located in the in-situ electrolytic cell, and the electrochemical workstation is electrically connected to the electrode assembly of the in-situ electrolytic cell;

When the in-situ electrolytic cell is subjected to electrocatalytic hydrogen production monitoring, the loss mode resonance sensor is placed under a laser emitted by a broadband light source, and the laser generates loss mode resonance on the surface of the loss mode resonance sensor.

Preferably, the loss mode resonance sensor comprises a planar waveguide layer, a semiconductor layer and a catalytic metal layer stacked from bottom to top, and an orthographic projection area of the semiconductor layer on the planar waveguide layer is smaller than a cross-sectional area of the planar waveguide layer.

Preferably, the planar waveguide layer is a cover glass, the semiconductor layer is an ITO material, and the catalytic metal layer is Pt particles.

Preferably, the electrode assembly in the in-situ electrolytic cell includes a working electrode, a reference electrode and a counter electrode, and the electrode clamps of the electrochemical workstation clamp the working electrode, the reference electrode and the counter electrode respectively.

Preferably, the electrolyte in the in-situ electrolytic cell is a dilute sulfuric acid solution, the semiconductor layer is reused as a working electrode, the reference electrode is an Ag/AgCl material, and the counter electrode is a Pt coil wire.

Preferably, the optical fiber transmission module is a multimode optical fiber, and the core diameter of the multimode optical fiber is 100-300 μm.

Preferably, a linear polarizer is provided between the broadband light source and the loss mode resonance sensor, and the linear polarizer is used to separate TE light and TM light in the loss mode resonance.

Preferably, a three-dimensional displacement stage is also provided in the in-situ electrolytic cell, and the loss mode resonance sensor is fixed on the three-dimensional displacement stage. The three-dimensional displacement stage is used to adjust the height between the loss mode resonance sensor and the ground so that the laser generates loss mode resonance on the surface of the loss mode resonance sensor.

Accordingly, the present invention also provides a method for in-situ monitoring of a planar optical waveguide for electrocatalytic hydrogen production, the method comprising:

S10, sequentially depositing a semiconductor layer and a catalytic metal layer on a surface of a planar waveguide layer to form a loss mode resonance sensor;

S20, connecting a broadband light source, a loss mode resonance sensor, and a spectrometer through a multimode optical fiber, and performing coupling and alignment on the multimode optical fiber;

S30, fixing the loss mode resonance sensor on a three-dimensional translation stage, and adjusting the height of the loss mode resonance sensor by the three-dimensional translation stage, so that the laser emitted by the broadband light source generates loss mode resonance on the surface of the loss mode resonance sensor;

S40, by adjusting the linear polarizer to separate the TE light and TM light in the loss mode resonance;

S50, placing the loss mode resonance sensor together with the three-dimensional displacement stage in an in-situ electrolytic cell filled with electrolyte, then clamping the electrode clamps of the electrochemical workstation onto the multiple electrodes in the in-situ electrolytic cell respectively, and adjusting the electrodes between the multiple electrodes by the electrochemical workstation to perform electrocatalytic hydrogen production in the in-situ electrolytic cell;

S60, monitors the changes in electrical signals during hydrogen bubble separation under constant potential conditions through an electrochemical workstation, and records the changes in optical signals collected by the spectrometer during electrocatalytic hydrogen production. The electrical and optical signals are analyzed by a data recording computer to achieve real-time in-situ monitoring of electrocatalytic hydrogen production.

Preferably, after performing step S30 and before performing step S40, the method further includes:

The loss mode resonance sensor is removed from the three-dimensional translation stage, and the planar waveguide layer without the semiconductor layer is fixed on the three-dimensional translation stage and placed together in an in-situ electrolytic cell filled with electrolyte for spectral baseline correction.

The beneficial effects of the present invention are as follows: Different from the prior art, the present invention provides a planar optical waveguide in-situ monitoring device for electrocatalytic hydrogen production and a monitoring method thereof, wherein the planar optical waveguide in-situ monitoring device comprises a broadband light source, an in-situ electrolytic cell, a loss mode resonance sensor, an electrochemical workstation and a spectrometer, wherein the broadband light source, the loss mode resonance sensor and the spectrometer are interconnected via an optical fiber transmission module, the loss mode resonance sensor is located in the in-situ electrolytic cell, the electrochemical workstation is electrically connected to an electrode assembly of the in-situ electrolytic cell, and when the in-situ electrolytic cell is subjected to electrocatalytic hydrogen production monitoring, the loss mode resonance sensor is placed under a laser emitted by the broadband light source, and the laser generates a loss mode resonance on the surface of the loss mode resonance sensor; the present invention has a loss mode resonance sensor. When electrocatalytic hydrogen production is carried out on the surface of the device, the laser emitted by the broadband light source generates loss mode resonance on the surface of the loss mode resonance sensor. The spectrometer can quantitatively reveal the amount of hydrogen produced in the electrocatalytic hydrogen production process according to the resonance wavelength drift of the loss mode resonance to sense the growth process of the bubbles at this stage. At the same time, the electrochemical workstation monitors the hydrogen bubble separation process in the electrocatalytic hydrogen production process according to the current changes between multiple electrodes in the in-situ electrolytic cell under constant potential conditions. Then, by studying the above-mentioned bubble behavior, its influence on the catalytic hydrogen production efficiency is analyzed, and the kinetic mechanism of the three-phase interface of the catalytic hydrogen production system is further deeply understood from the microscopic level, and the structural effect relationship of the catalytic surface is clarified, which is further beneficial to the improvement of the catalytic hydrogen production efficiency in the electrocatalytic hydrogen production industry.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG1 is a structural block diagram of a planar optical waveguide in-situ monitoring device for electrocatalytic hydrogen production provided by an embodiment of the present invention;

2 is a structural block diagram of an electrochemical loss mode resonance platform in a planar optical waveguide in-situ monitoring device for electrocatalytic hydrogen production provided by an embodiment of the present invention;

FIG3 is a flow chart of a method for in-situ monitoring of a planar optical waveguide for electrocatalytic hydrogen production provided by an embodiment of the present invention.

Detailed ways

The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

Electrocatalytic hydrogen production involves a complex reaction process that can be divided into two stages: before and after bubble generation. In the discharge reaction process before bubble generation, active hydrogen is first generated and adsorbed on the active sites on the catalyst surface, and at the same time, the liquid phase reactants on the catalyst surface also change.

Therefore, the present invention can understand the reaction process at this stage by monitoring the refractive index changes of the solid and liquid media on the catalyst surface, including the generation of active hydrogen and the changes of the liquid phase reaction medium on the catalyst surface, followed by the generation, growth and detachment stages of bubbles. Before the bubble generation, the change in film thickness has been basically stable, so the behavior of the bubbles at this stage will cause a significant change in the refractive index of the catalyst surface. At the same time, the present invention can sense the growth and detachment process of the bubbles at this stage through the loss mode resonance sensor 9, and analyze its impact on the catalytic hydrogen production efficiency by studying the bubble behavior. In contrast, the use of an electrochemical loss mode resonance platform can monitor the hydrogen production reaction process online in situ, with the advantages of fast response, corrosion resistance and small size. At the same time, the data collected synchronously by combining optics and electricity can verify the accuracy of the monitoring results.

In view of the difficulty in in-situ monitoring of the electrocatalytic hydrogen production process in the prior art, the present invention provides a planar optical waveguide in-situ monitoring device for electrocatalytic hydrogen production and a monitoring method thereof. The purpose of the present invention is to provide a new technical implementation method for the study of catalytic hydrogen production processes by real-time monitoring of the changes in the reaction medium of electrocatalytic water splitting hydrogen production and the dynamic behavior of bubbles generated on the surface of the electrocatalytic film. This method can provide an in-depth understanding of the dynamic mechanism of the three-phase interface of the catalytic hydrogen production system at a microscopic level, and clarify the structural effect relationship of the catalytic surface, providing a planar optical waveguide in-situ monitoring device that can monitor the electrocatalytic hydrogen production process in situ.

Specifically, please refer to Figures 1 and 2, Figure 1 is a structural block diagram of a planar optical waveguide in-situ monitoring device for electrocatalytic hydrogen production provided by an embodiment of the present invention; Figure 2 is a structural block diagram of an electrochemical loss mode resonance platform in a planar optical waveguide in-situ monitoring device for electrocatalytic hydrogen production provided by an embodiment of the present invention; wherein the present invention provides a planar optical waveguide in-situ monitoring device for electrocatalytic hydrogen production comprising at least a broadband light source 1, an in-situ electrolytic cell, a loss mode resonance sensor 9, an electrochemical workstation 5 and a spectrometer 6 (Avantes type spectrometer);

The broadband light source 1, the loss mode resonance sensor 9 and the spectrometer 6 are interconnected via an optical fiber transmission module 10, the loss mode resonance sensor 9 is located in the in-situ electrolytic cell, and the electrochemical workstation 5 is electrically connected to the electrode assembly of the in-situ electrolytic cell.

Specifically, when the in-situ electrolytic cell is monitored for electrocatalytic hydrogen production, the loss mode resonance sensor 9 is placed under the laser emitted by the broadband light source 1. The laser generates loss mode resonance on the surface of the loss mode resonance sensor 9. The spectrometer 6 is used to quantitatively reveal the amount of hydrogen produced according to the resonance wavelength drift of the loss mode resonance. The electrochemical workstation 5 is used to monitor the hydrogen bubble separation process according to the current change under constant potential conditions.

In the embodiment of the present invention, the loss mode resonance sensor 9 includes a planar waveguide layer, a semiconductor layer and a catalytic metal layer stacked from bottom to top, and the orthographic projection area of the semiconductor layer on the planar waveguide layer is smaller than the cross-sectional area of the planar waveguide layer.

In particular, the loss mode resonance sensor 9 is capable of simultaneously performing electrochemical and optical measurements, in particular loss mode resonance (LMR), to monitor the growth of hydrogen on the working electrode 2 .

Furthermore, loss mode resonance (LMR) is a resonance produced by the mutual coupling between the evanescent wave and the detuned mode in the conductive metal oxide, which can be excited by transverse electric (TE) or transverse magnetic (TM) polarized light. This resonance causes the intensity of the light transmitted in the optical waveguide to drop sharply, thus forming a resonance trough. The LMR effect is very sensitive to the external refractive index. When the external refractive index changes, the resonance trough of the LMR will also change accordingly, reflecting the change in the refractive index of the external material. Therefore, the measured value can be obtained by refractive index conversion.

Preferably, the planar waveguide layer is a cover glass, the semiconductor layer is an ITO material, and the catalytic metal layer is Pt particles; wherein the cover glass can be used as a planar waveguide, the semiconductor layer can be reused as a working electrode 2 in an in-situ electrolytic cell for electrocatalytic hydrogen production, and the catalytic metal layer is used as a catalyst for electrocatalytic hydrogen production.

In the embodiment of the present invention, the electrode assembly in the in-situ electrolytic cell includes a working electrode 2, a reference electrode 3 and a counter electrode 4, and the electrode clamps of the electrochemical workstation 5 clamp the working electrode 2, the reference electrode 3 and the counter electrode 4 respectively.

The electrolyte in the in-situ electrolytic cell is a dilute sulfuric acid solution, the working electrode 2 is an ITO material, the reference electrode 3 is an Ag/AgCl material, and the counter electrode 4 is a Pt coil wire.

Please refer to Figures 1 and 2. The broadband light source 1, the loss mode resonance sensor 9 and the spectrometer 6 are interconnected through an optical fiber transmission module 10. The optical fiber transmission module 10 is a multimode optical fiber. The core diameter of the multimode optical fiber is 100 to 300 μm. The laser (visible light band) emitted by the broadband light source 1 generates a loss mode resonance on the surface of the loss mode resonance sensor 9. The spectrometer 6 receives the optical signal generated by the loss mode resonance through the multimode optical fiber, and transmits the optical signal to the data recording computer 7 to analyze the optical signal, so as to realize real-time in-situ monitoring of electrocatalytic hydrogen production.

Specifically, after the electrochemical loss mode resonance platform shown in Figure 2 is prepared, the visible light emitted by the broadband light source 1 is guided in the planar waveguide layer in the loss mode resonance sensor 9. When the mode guided in the planar waveguide layer undergoes a transformation and is instead guided in the semiconductor layer covering the planar waveguide layer, the LMR resonance phenomenon can be observed.

When electrochemical hydrogen evolution occurs on the semiconductor layer surface of the loss mode resonance sensor 9, the refractive index around it changes, causing the LMR resonance wavelength to drift. Analysis of the wavelength drift signal can monitor the bubble dynamics of the hydrogen production process online in situ. At the same time, analysis can be performed based on the LMR resonance wavelength, and the amount of hydrogen production can be quantitatively revealed by the drift of the resonance wavelength. At the same time, the electrochemical workstation 5 can monitor the hydrogen bubble separation process based on the current change under constant potential conditions.

In an embodiment of the present invention, a linear polarizer 8 is arranged between the broadband light source 1 and the loss mode resonance sensor 9. The linear polarizer 8 is used to separate the TE light and the TM light in the loss mode resonance, thereby increasing the visibility of the LMR. The maximum visibility can be achieved by adjusting the linear polarizer 8 in a manner that makes the electric field axis parallel or perpendicular to the surface of the semiconductor layer.

In an embodiment of the present invention, a three-dimensional displacement platform 12 is also provided in the in-situ electrolytic cell, and the loss mode resonance sensor 9 is fixed on the three-dimensional displacement platform 12. The three-dimensional displacement platform 12 is used to adjust the height between the loss mode resonance sensor 9 and the ground so that the laser generates loss mode resonance on the surface of the loss mode resonance sensor 9.

Correspondingly, referring to FIG. 3 , the present invention further provides a planar optical waveguide in-situ monitoring method for electrocatalytic hydrogen production, the method comprising:

S10 , a semiconductor layer and a catalytic metal layer are sequentially deposited on a surface of a planar waveguide layer to form a loss mode resonance sensor 9 .

Specifically, S10 also includes:

First, ITO was deposited on a cover glass with a thickness of 150 microns by magnetron sputtering. The size of the cover glass was 18 mm*18 mm. The specific process was as follows: using an ITO target material with a ratio of In ₂ O ₃ :SnO ₂ =90:10wt% and a purity of 99.99%, a semiconductor film (7 mm*16 mm) of ITO material was deposited on the surface of the cover glass under the conditions of an Ar partial pressure of 0.1 Pa and a current intensity of 150 mA. The deposition rate was 0.06 nm per second, and a semiconductor layer with a thickness of 100 nm was deposited.

The semiconductor layer is not deposited on the entire area of the cover glass to avoid interference with the transmission spectrum caused by deposition on the lateral surface of the waveguide. After the ITO film is deposited on the cover glass, Pt particles are deposited on the surface of the ITO film by magnetron sputtering to form a catalytic metal layer.

S20, connecting the broadband light source 1, the loss mode resonance sensor 9 and the spectrometer 6 via a multimode optical fiber, and performing coupling alignment on the multimode optical fiber.

Specifically, S20 also includes:

Please refer to FIG. 2 . First, the optical fiber holder 11 is installed on the optical breadboard 13. The optical breadboard 13 with positioning grooves is selected in the present invention. The bottom of the optical fiber holder 11 has a matching tongue, which can be tightly fitted into the positioning groove of the optical breadboard 13 to achieve coupling alignment of the optical fiber.

Afterwards, a multimode optical fiber with a core diameter of 200 microns is used to connect the broadband light source 1, the loss mode resonance sensor 9 and the spectrometer 6.

Further, a linear polarizer 8 is placed in front of the fiber holder 11 near the side of the broadband light source 1. The linear polarizer 8 can help separate the TE light and the TM light in the loss mode resonance, thereby increasing the visibility of the LMR. By adjusting the polarizer in such a way that the electric field axis is parallel or perpendicular to the film surface, the maximum visibility can be achieved.

S30, fixing the loss mode resonance sensor 9 on the three-dimensional translation stage 12, and adjusting the height of the loss mode resonance sensor 9 through the three-dimensional translation stage 12, so that the laser emitted by the broadband light source 1 generates loss mode resonance on the surface of the loss mode resonance sensor 9.

Specifically, S30 also includes:

The spectral baseline correction is performed directly after the optical fiber coupling alignment. Then the prepared loss mode resonance sensor 9 with ITO film is adjusted in height in the air through the three-dimensional displacement stage 12. When the spectrum shows LMR resonance, the height of the cover glass at this time can enable the light transmitted by the multimode optical fiber to be guided through the cover glass, so that the laser emitted by the broadband light source 1 generates loss mode resonance on the surface of the loss mode resonance sensor 9.

Afterwards, the loss mode resonance sensor 9 is removed from the three-dimensional displacement stage 12, and the planar waveguide layer without the semiconductor layer is fixed on the three-dimensional displacement stage 12 and placed together in an in-situ electrolytic cell filled with electrolyte for spectral baseline correction. The specific process is as follows:

The cover glass without ITO film coating is fixed on the three-dimensional translation stage 12 by mechanical fixing, and then placed together with the three-dimensional translation stage 12 into a cubic glass container electrolytic cell (in-situ electrolytic cell) with a size of 10cm×10cm×10cm and filled with dilute sulfuric acid solution as the electrolyte solution for spectral baseline correction.

S40 , separating the TE light and the TM light in the loss mode resonance by adjusting the linear polarizer 8 .

Specifically, S40 also includes:

After the spectral baseline correction, the prepared cover glass with the ITO film is fixed on the three-dimensional translation stage 12 by mechanical fixing, and the TE mode and TM mode in the LMR resonance are separated by adjusting the linear polarizer 8.

S50, placing the loss mode resonance sensor 9 together with the three-dimensional displacement stage 12 in an in-situ electrolytic cell filled with electrolyte, then clamping the electrode clamps of the electrochemical workstation 5 onto the multiple electrodes in the in-situ electrolytic cell respectively, and adjusting the electrodes between the multiple electrodes through the electrochemical workstation 5 to perform electrocatalytic hydrogen production in the in-situ electrolytic cell.

Specifically, S50 also includes:

The electrochemical catalytic hydrogen production process is carried out in an in-situ electrolytic cell (conventional three-electrode system), and the electrolytic cell adopts a cubic glass container with a size of 10cm×10cm×10cm. A cover glass (100nm film) deposited with an ITO film is used as the working electrode 2, and the cover glass area is 7mm×16mm. Ag/AgCl is used as the reference electrode 3 (providing a stable standard potential as a reference point for potential measurement), a platinum (Pt) coil wire (diameter 0.5mm, 10 coils of 8mm diameter) is used as the counter electrode 4, and the electrolyte solution is a dilute sulfuric acid solution. The working electrode 2, the reference electrode 3 and the counter electrode 4 are connected to the electrochemical workstation 5 respectively with copper tape, and the voltage is adjusted to the voltage (1.6V～2V) at which hydrogen production occurs by the electrochemical workstation 5 to carry out electrocatalytic hydrogen production.

S60, monitor the changes in electrical signals during the hydrogen bubble separation process under constant potential conditions through the electrochemical workstation 5, and record the changes in optical signals collected by the spectrometer 6 during the electrocatalytic hydrogen production process, and analyze the electrical signals and optical signals through the data recording computer 7 to achieve real-time in-situ monitoring of the electrocatalytic hydrogen production.

Specifically, S60 also includes:

The electrolysis was performed for 120 seconds under constant potential conditions at the electrochemical workstation 5 with a sampling frequency of 100 Hz. The current changes during the separation of hydrogen bubbles were monitored, and the changes in the optical signals collected by the spectrometer 6 during the electrocatalytic hydrogen production process were recorded. By analyzing the wavelength drift during the electrocatalytic hydrogen production process and the electrical signals in the electrochemical workstation 5, the electrocatalytic hydrogen production can be monitored in real time in situ.

Compared with the prior art, the present invention has the following beneficial effects:

The present invention uses an electrochemical loss mode resonance platform as a monitoring device, which can monitor the process of electrocatalytic hydrogen production in real time in situ. The electrochemical loss mode resonance platform can monitor the electrocatalytic hydrogen production in real time in situ by optically monitoring the optical signal of wavelength drift caused by the change of the surrounding refractive index during the catalytic process and the analysis of the electrical signal of the electrochemical workstation 5 during the catalytic process. The present invention can effectively solve the problem of the difficulty of monitoring the electrochemical hydrogen production process in the prior art through planar waveguide sensing and real-time monitoring system, provide a new in-situ real-time monitoring method for hydrogen production process research, qualitatively and quantitatively reveal the kinetic reaction process and microscopic mechanism of the three-phase surface interface of catalytic hydrogen production from the micro-nano scale, establish a bridge from micro to macro, and construct a new evaluation method for the performance evaluation of hydrogen production system.

In summary, different from the prior art, the present invention provides a planar optical waveguide in-situ monitoring device for electrocatalytic hydrogen production and a monitoring method thereof. The planar optical waveguide in-situ monitoring device at least comprises a broadband light source 1, an in-situ electrolytic cell, a loss mode resonance sensor 9, an electrochemical workstation 5 and a spectrometer 6. When the in-situ electrolytic cell is subjected to electrocatalytic hydrogen production monitoring, the loss mode resonance sensor 9 is placed under the laser emitted by the broadband light source 1. The laser generates loss mode resonance on the surface of the loss mode resonance sensor 9. The spectrometer 6 is used to quantitatively reveal the amount of hydrogen produced according to the drift of the resonance wavelength of the loss mode resonance. The electrochemical workstation 5 is used to monitor the hydrogen bubble separation process according to the current change under constant potential conditions. During electrocatalytic hydrogen production, the laser emitted by the broadband light source 1 generates loss mode resonance on the surface of the loss mode resonance sensor 9. The spectrometer 6 can quantitatively reveal the amount of hydrogen produced during the electrocatalytic hydrogen production process based on the resonance wavelength drift of the loss mode resonance to sense the growth process of the bubbles at this stage. At the same time, the electrochemical workstation 5 monitors the hydrogen bubble separation process during the electrocatalytic hydrogen production process based on the current changes between multiple electrodes in the in-situ electrolytic cell under constant potential conditions. The influence of the above-mentioned bubble behavior on the catalytic hydrogen production efficiency is analyzed by studying the above-mentioned bubble behavior, and the kinetic mechanism of the three-phase interface of the catalytic hydrogen production system is further deeply understood from the microscopic level, and the structural effect relationship of the catalytic surface is clarified, which is further beneficial to the improvement of the catalytic hydrogen production efficiency of the electrocatalytic hydrogen production industry.

The above embodiments only express the implementation methods of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for those of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims (10)

1. The planar optical waveguide in-situ monitoring device for electrocatalytic hydrogen production is characterized by comprising a broadband light source, an in-situ electrolytic cell, a loss mode resonance sensor, an electrochemical workstation and a spectrometer, wherein the broadband light source, the loss mode resonance sensor and the spectrometer are mutually connected through an optical fiber transmission module, the loss mode resonance sensor is positioned in the in-situ electrolytic cell, and the electrochemical workstation is electrically connected with an electrode assembly of the in-situ electrolytic cell;

When the in-situ electrolytic cell is monitored for electrocatalytic hydrogen production, the loss mode resonance sensor is placed under laser emitted by the broadband light source, and loss mode resonance is generated on the surface of the loss mode resonance sensor by the laser.

2. The device of claim 1, wherein the loss mode resonance sensor comprises a planar waveguide layer, a semiconductor layer and a catalytic metal layer stacked from bottom to top, and the orthographic projection area of the semiconductor layer on the planar waveguide layer is smaller than the cross-sectional area of the planar waveguide layer.

3. The electrocatalytic hydrogen generating planar optical waveguide in-situ monitoring device as set forth in claim 2, wherein the planar waveguide layer is a cover slip, the semiconductor layer is an ITO material, and the catalytic metal layer is Pt particles.

4. The planar lightwave circuit of claim 2, wherein the electrode assembly comprises a working electrode, a reference electrode, and a counter electrode, and wherein the electrode clamps of the electrochemical workstation clamp the working electrode, the reference electrode, and the counter electrode, respectively.

5. The device for in-situ monitoring of planar lightwave circuit of hydrogen production by electrocatalysis according to claim 4, wherein electrolyte in the in-situ electrolytic cell is dilute sulfuric acid solution, the semiconductor layer is multiplexed to the working electrode, the reference electrode is Ag/AgCl material, and the counter electrode is Pt coil wire.

6. The device of claim 1, wherein the fiber transmission module is a multimode fiber, and the diameter of the core layer of the multimode fiber is 100-300 μm.

7. The device of claim 6, wherein a linear polarizer is disposed between the broadband light source and the loss mode resonance sensor, the linear polarizer being configured to separate TE light and TM light in the loss mode resonance.

8. The device for in-situ monitoring of planar lightwave circuit of claim 6, wherein the in-situ cell is further provided with a three-dimensional displacement stage, the loss mode resonance sensor is fixed on the three-dimensional displacement stage, and the three-dimensional displacement stage is used for adjusting the height between the loss mode resonance sensor and the ground so as to generate loss mode resonance on the surface of the loss mode resonance sensor.

9. A method of monitoring a planar lightwave circuit in-situ monitoring device as claimed in any of claims 1 to 8, the method comprising:

s10, sequentially depositing a semiconductor layer and a catalytic metal layer on the surface of a planar waveguide layer to form a loss mode resonance sensor;

s20, connecting a broadband light source, the loss mode resonance sensor and a spectrometer through a multimode optical fiber, and carrying out coupling alignment on the multimode optical fiber;

S30, fixing the loss mode resonance sensor on a three-dimensional displacement table, and adjusting the height of the loss mode resonance sensor through the three-dimensional displacement table so as to enable the laser emitted by the broadband light source to generate loss mode resonance on the surface of the loss mode resonance sensor;

S40, separating TE light and TM light in the loss mode resonance by adjusting the linear polarizer;

S50, placing the loss mode resonance sensor and the three-dimensional displacement table in an in-situ electrolytic cell filled with electrolyte, respectively clamping a plurality of electrodes in the in-situ electrolytic cell by electrode clamps of an electrochemical workstation, and adjusting the electrodes among the plurality of electrodes by the electrochemical workstation so as to perform electrocatalytic hydrogen production in the in-situ electrolytic cell;

S60, monitoring the electric signal change in the hydrogen bubble separation process under the constant potential condition through the electrochemical workstation, recording the optical signal change acquired by the spectrometer in the electrocatalytic hydrogen production process, and analyzing the electric signal and the optical signal through a data recording computer so as to realize real-time in-situ monitoring of electrocatalytic hydrogen production.

10. The method of claim 9, further comprising, after step S30 and before step S40:

and removing the loss mode resonance sensor from the three-dimensional displacement table, fixing the plane waveguide layer which is not plated with the semiconductor layer on the three-dimensional displacement table, and placing the plane waveguide layer and the plane waveguide layer together in an in-situ electrolytic cell filled with electrolyte for correcting the spectrum baseline.