CN104390941A - Method for testing photochemical reaction of solid-liquid interface by using cuvette - Google Patents

Abstract

The invention belongs to the field of spectrum testing in optical experiments, and discloses a method for testing photochemical reactions at solid-liquid interfaces by using a cuvette. The specific steps of the method are as follows: the flake solid sample is placed in the cavity of the cuvette body A, and the surface to be measured faces the front of the cuvette; the liquid sample is dripped into the cavity, and the liquid sample will infiltrate the flake solid sample. The test surface of the flake solid sample is covered with a liquid layer with a thickness not greater than 1mm; cover the upper cover B on the cuvette body A. In the present invention, flake solid samples and liquid samples are simultaneously contained in this cuvette with thin-layer structure characteristics, and it is more convenient and quick to directly test the characteristic spectrum of the transient species produced by the photochemical reaction at the solid-liquid interface, and directly infer that the solid Photochemical reaction processes and mechanisms at the liquid interface.

Description

A method of testing solid-liquid interface photochemical reaction with cuvette

technical field

The invention relates to the technical field of spectrum measurement in optical experiments, in particular to a method for testing photochemical reactions at solid-liquid interfaces with a cuvette.

Background technique

As an accessory of spectral analysis instruments, cuvettes are widely used in spectrophotometers, laser flash photolysis spectrometers, blood line protein analyzers, particle size analyzers and other spectral analysis instruments. Up to now, the standard, micro, semi-micro or other cuvettes on the market are used to contain liquid samples (transparent solutions, suspensions, emulsions, etc.) or powder samples to study their spectral properties , Quantitative and qualitative analysis of substances.

For the photochemical reaction process and mechanism of the solid-liquid (referred to as solid-liquid) interface, most of them are indirectly speculated by monitoring/detecting the concentration changes of reactants/reaction products, or with theoretical calculations. For example: in the laser flash photolysis test, in order to directly obtain the characteristic spectrum of the transient species produced by the photochemical reaction at the solid-liquid interface, in order to directly infer the photochemical reaction process and mechanism of the solid-liquid interface, some researchers directly sampled the solid-liquid interface. After the liquid sample was drip-coated on the surface, it was fixed on the laser flash photolysis spectrometer without any protective measures, and then the spectral test was carried out. However, factors such as the volatility of the solvent and the uneven distribution of the solution on the surface of the solid sample seriously affect the repeatability and reliability of the obtained data. Moreover, some solutions are acidic, alkaline or otherwise corrosive, which will cause damage to equipment.

Contents of the invention

The purpose of the invention is to address the above problems and provide a method for testing the photochemical reaction at the solid-liquid interface with a cuvette. By directly testing the characteristic spectra of the transient species produced by the photochemical reaction at the solid-liquid interface, the process and mechanism of the photochemical reaction at the solid-liquid interface can be directly inferred.

The technical scheme of the present invention: a method for testing the photochemical reaction at the solid-liquid interface with a cuvette, the cuvette includes a cuvette body A and an upper cover B, and the upper cover B is covered on the cuvette body A Inner surface. The cavity of the cuvette body A is a cuboid structure, the length of the cavity is not less than 5mm, the width is not greater than 5mm, and the height is not less than 5mm. The inner surface of the cuvette body A is a right-angled inner surface (shown in Figures 1-4) or a sloped inner surface (shown in Figures 5-8). The concrete steps of method of the present invention are as follows:

Step 1: Place the flake solid sample in the cavity of the cuvette body A, with the surface to be tested facing the front side 1 of the cuvette;

Step 2: Drop the liquid sample into the cavity, the liquid sample will infiltrate the flake solid sample, and cover the surface of the flake solid sample with a liquid layer with a thickness not greater than 1mm;

Step 3: Put the upper cover B on the cuvette body A

(1) If the flake solid sample is opaque, fix the cuvette containing the sample on the spectroscopic analysis instrument for photochemical reaction test. When the light beam reaches the solid-liquid interface, reflection occurs on the surface of the flake solid sample. The final optical signal is captured by the detector, and then the characteristic spectrum of the transient species produced by the photochemical reaction at the solid-liquid interface is tested;

(2) If the flake solid sample is transparent or translucent, and the back 5 of the cuvette body A is also transparent or translucent, it is necessary to paste reflective paper or reflective film on the back 5 of the cuvette body A, and then put The cuvette containing the sample is fixed on the spectroscopic analysis instrument for photochemical reaction test. When the light beam reaches the solid-liquid interface, even if the light beam penetrates the flake solid sample, it will be reflected on the reflective paper or reflective film. After reflection The optical signal is captured by the detector, and then the characteristic spectrum of the transient species produced by the photochemical reaction at the solid-liquid interface is tested.

The spectroscopic analysis instrument is a laser flash photolysis spectrometer or other instruments that obtain spectral signals through light reflection.

The reflective paper or reflective film is aluminum foil paper, gold foil paper or other materials with reflective properties.

The front of the cuvette body A is made of colorless transparent quartz glass, colorless transparent optical glass, colorless transparent ordinary glass or colorless transparent plastic; the other sides of the cuvette body A are made of glass or plastic production.

The sheet-like solid sample is a metal sheet or a non-metal sheet loaded with a thin film. The metal sheet is unmodified or chemically or physically modified, such as one of titanium sheet, silicon sheet, stainless steel sheet and the like. The non-metallic sheet loaded with film is one of plastic substrates, glass substrates, etc. loaded or not loaded with films, such as: non-conductive plastic substrates, ITO/PEN flexible conductive substrates, ITO/PET flexible conductive substrates, non-conductive plastic substrates, etc. One of conductive glass, conductive glass, etc.

The liquid sample can be transparent to opaque.

The thin film is one of doped or undoped metal compound thin film, non-metallic compound thin film or other thin films. Such as: titanium oxide, zinc oxide, aluminum oxide, cadmium sulfide, zinc sulfide, molybdenum sulfide, cadmium antimonide, bismuth vanadate, poly 3,4-ethylenedioxythiophene, polyphenylene sulfide, polyacetylene, polyphenylene , polyacene, polypyrrole, polythiophene and other films or a combination of several.

The film can be transparent to opaque.

The beneficial effect of the present invention is: Compared with the experimental method of indirectly obtaining the photochemical reaction data of the solid-liquid interface by monitoring/detecting the concentration change of the reactant/reaction product, or the method of cooperating with the theoretical calculation, the present invention uses the flake solid sample It can be more convenient and quick to directly test the characteristic spectrum of the transient species produced by the photochemical reaction at the solid-liquid interface, and directly deduce the photochemical reaction process of the solid-liquid interface. and mechanism. In addition, compared to the experimental method of drip-coating liquid samples on solid samples, the covered cuvette provided by the invention can well avoid the volatilization of solvents, the corrosion of instruments and equipment by the acidity and alkalinity of the solution, and the measured The repeatability and reliability of data will be greatly improved. At the same time, the extremely thin liquid layer will not have any impact on the collection of spectral information.

Description of drawings

Fig. 1 is a schematic diagram of a cuvette body A with a right-angle inner edge surface.

Fig. 2 is a schematic diagram of a cuvette upper cover B with a right-angled inner edge surface.

Fig. 3 is a top view of a cuvette body A with a right-angle inner edge surface.

Fig. 4 is a left side view of a cuvette body A with a right-angle inner edge surface.

Fig. 5 is a schematic diagram of a cuvette body A with a sloped inner edge surface.

Fig. 6 is a schematic diagram of a cuvette upper cover B with a sloping inner edge surface.

Fig. 7 is a top view of a cuvette body A with a sloped inner edge surface.

Fig. 8 is a left side view of the cuvette body A with a sloped inner edge surface.

In the figure: 1 front; 2 bottom; 3 left side; 4 right side; 5 back;

a The length of the cavity of the cuvette body A; b The cavity width of the cuvette body A;

c The cavity of cuvette body A is high.

Detailed ways

The specific implementation manners of the present invention will be further described below in conjunction with the drawings and technical solutions.

Example 1

With reference to Fig. 1 to Fig. 8, this embodiment provides a kind of method for testing the photochemical reaction of solid-liquid interface with cuvette, and described cuvette comprises body A and loam cake B, and the inner edge surface of this cuvette body A It is a right-angle inner edge surface, the front surface 1 is made of colorless transparent quartz glass, the bottom surface 2 is made of frosted glass, and the rest of the surfaces are made of colorless transparent glass. The cavity volume of the cuvette is a×b×c=30mm×0.8mm×30mm. Place a silicon wafer with a thickness of 0.5mm (length×width=27mm×27mm) engraved with nanowires in the cavity of the cuvette body A, with the nanowires facing the front side 1, and then drop 10 ^-4 into the cavity The phenol solution of M, the solution will immerse the silicon wafer, and a layer of 0.3mm thick liquid layer is formed on the side engraved with nanowires, cover the upper cover B on the cuvette body A, and then put the colorimetric cuvette containing the sample The dish is fixed on the laser flash photolysis instrument, and the transient absorption spectrum test is carried out.

Example 2

With reference to Fig. 1 to Fig. 8, this embodiment provides a kind of method for testing the photochemical reaction of solid-liquid interface with cuvette, and described cuvette comprises body A and loam cake B, and the inner edge surface of this cuvette body A It is a slope type inner edge surface, the front surface 1 is made of colorless transparent quartz glass, the bottom surface 2 is made of frosted glass, and the rest of the surfaces are made of colorless transparent glass. The cavity volume of the cuvette is a×b×c=45mm×1.2mm×30mm. Place a FTO conductive glass with a thickness of 1mm (length×width=40mm×25mm) deposited with a white translucent titanium dioxide film in the cavity of the cuvette body A, the white translucent titanium dioxide film faces the front side 1, and then faces into the cavity Drop in 10 ^-3 M chlorobenzene solution, the solution will immerse the FTO conductive glass sample, forming a layer of 0.2mm thick liquid layer on the side of the titanium dioxide film, cover the upper cover B on the cuvette body A, and place The back side 5 of the cuvette body A is pasted with aluminum foil paper, and then the cuvette is fixed on the laser flash photolysis instrument for the transient absorption spectrum test.

Example 3

With reference to Fig. 1 to Fig. 8, this embodiment provides a kind of method for testing the photochemical reaction of solid-liquid interface with cuvette, and described cuvette comprises body A and loam cake B, and the inner edge surface of this cuvette body A It is a sloping inner edge surface, the front 1 is made of colorless transparent glass, the bottom 2 and the back 5 are made of frosted glass, and the rest of the surfaces are made of colorless transparent glass. The cavity volume in the cuvette is a×b×c=30mm×0.5mm×30mm. Place a PEN flexible substrate with a thickness of 0.1mm (length×width=25mm×25mm) deposited with a yellow translucent bismuth vanadate film in the cavity of the cuvette body A, with the yellow translucent bismuth vanadate film facing the front side 1 , and then drop 10 ^-3 M chlorobenzene solution into the chamber, the solution will immerse the PEN flexible substrate sample, forming a layer of 0.4mm thick liquid layer on the side of the bismuth vanadate film, cover the upper cover B with a colorimetric Then fix the cuvette on the laser flash photolysis instrument for transient absorption spectrum test.

Claims (10)

1. a method for testing solid-liquid interface photochemical reaction with cuvette, it is characterized in that, described cuvette comprises cuvette body A and loam cake B, and described loam cake B is covered in cuvette body The inner edge of A; the cavity of the cuvette body A is a cuboid structure, the length of the cavity is not less than 5mm, the width is not more than 5mm, and the height is not less than 5mm; the inner edge of the cuvette body A is Right-angle inner edge or slope inner edge; the steps are as follows: Step 1: Place the flake solid sample in the cavity of the cuvette body A, with the surface to be tested facing the front of the cuvette; Step 2: Drop the liquid sample into the cavity, the liquid sample will infiltrate the flake solid sample, and cover the surface of the flake solid sample with a liquid layer with a thickness not greater than 1mm; Step 3: Put the upper cover B on the cuvette body A (1) If the flaky solid sample is opaque, fix the cuvette containing the sample on the spectroscopic analysis instrument for photochemical reaction test. When the light beam reaches the solid-liquid interface, reflection occurs on the surface of the flaky solid sample. The optical signal is captured by the detector, and the characteristic spectrum of the transient species produced by the photochemical reaction at the solid-liquid interface is tested; (2) If the flake solid sample is transparent or translucent, the back of the cuvette body A is also transparent or translucent, and reflective paper or reflective film is pasted on the back of the cuvette body A, and the cuvette containing the sample is The color dish is fixed on the spectrum analysis instrument for photochemical reaction test. When the light beam reaches the solid-liquid interface, the light beam penetrates the flake solid sample and reflects on the reflective paper or reflective film. The reflected light signal is captured by the detector. The characteristic spectrum of the transient species produced by the photochemical reaction at the solid-liquid interface was tested. 2. The method according to claim 1, wherein the spectroscopic analysis instrument is a laser flash photolysis spectrometer or other instruments that obtain spectral signals by light reflection. 3. The method according to claim 1 or 2, characterized in that the reflective paper or reflective film is aluminum foil paper, gold foil paper or other materials with reflective properties. 4. The method according to claim 1 or 2, wherein the front of the cuvette body A is colorless transparent quartz glass, colorless transparent optical glass, colorless transparent ordinary glass or colorless transparent plastic Made; the other surfaces of the cuvette body A are made of glass or plastic. 5. The method according to claim 3, wherein the front of the cuvette body A is made of colorless transparent quartz glass, colorless transparent optical glass, colorless transparent common glass or colorless transparent plastic ; The other faces of the cuvette body A are made of glass or plastic. 6. according to the described method of claim 1,2 or 5, it is characterized in that, described flake solid sample is metal sheet or the non-metallic sheet that is loaded with thin film; Described metal sheet is unmodified or through A metal sheet modified by chemical or physical methods; the non-metal sheet is a plastic substrate or a glass substrate. 7. The method according to claim 3, characterized in that, the sheet-like solid sample is a metal sheet or a non-metallic sheet loaded with a thin film; the metal sheet is unmodified or through chemical and physical methods A modified metal sheet; the non-metal sheet is a plastic substrate or a glass substrate. 8. The method according to claim 4, characterized in that, the sheet-like solid sample is a metal sheet or a non-metallic sheet loaded with a thin film; the metal sheet is unmodified or through chemical and physical methods A modified metal sheet; the non-metal sheet is a plastic substrate or a glass substrate. 9. The method according to claim 1, 2, 5, 7 or 8, wherein the liquid sample is transparent to opaque. 10. The method according to claim 6, characterized in that: the film is doped or undoped metal compound film, non-metal compound film or other films; and the film is transparent to opaque.