Boron-doped diamond electrode surface crystallization treatment method

Abstract

The invention discloses a boron-doped diamond electrode surface crystallization treatment method. The method comprises the following steps: respectively obtaining a boron-doped diamond electrode and fullerene C60; placing the boron-doped diamond electrode on an objective table of an electron beam vacuum evaporator, and placing fullerene C60 in a crucible of the electron beam vacuum evaporator; and the electron beam vacuum evaporator is controlled to be started according to preset parameters, so that the surface of the boron-doped diamond electrode is subjected to crystallization treatment, and the target boron-doped diamond electrode is generated. Therefore, crystal fullerene C60 can be uniformly deposited on the surface of the boron-doped diamond electrode, the crystal fullerene C60 has the sp2 hybridization characteristic, the occurrence rate of adsorbed oxygen free radicals is increased, ozone generation is promoted, the crystal fullerene C60 is not prone to falling off due to high adhesiveness, and higher stability is ensured.

Description

Technical Field

[0001] The present application relates to the technical field of surface treatment of boron-doped diamond electrodes, and in particular to a method for crystallization treatment of the surface of a boron-doped diamond electrode. Background Art

[0002] Ozone water has a strong oxidizing ability and can effectively kill a variety of bacteria and viruses, showing excellent disinfection and deodorization performance while ensuring no residue. Compared with chlorine disinfectants, a major advantage of ozone water is that it does not induce the production of drug-resistant bacteria. It has attracted much attention and has been widely used.

[0003] Ozone is usually prepared by electrolysis. In this method, boron-doped diamond is used as an anode in a zero-gap electrolytic cell. Electricity is applied to it to induce an electrochemical reaction, decomposing water molecules into oxygen and hydrogen, and generating ozone in the process. At the same time, when boron-doped diamond reacts, adsorption intermediates such as hydroxyl radicals, adsorbed oxygen radicals and oxygen molecules are generated on its surface. Among them, oxygen molecules can participate in desorption in the oxygen evolution reaction and can also react with oxygen radicals to form adsorbed ozone. However, due to the competitive reaction between the oxygen evolution reaction and the formation of ozone, the adsorbed oxygen radicals quickly combine with oxygen molecules before desorption, resulting in a low incidence of ozone.

[0004] In order to increase the occurrence rate of ozone, an sp2 hybrid layer is formed on the surface of diamond, which can effectively enhance the conductivity and specific surface area, thereby promoting the generation of ozone. At present, the main ways to obtain the sp2 hybrid surface layer include: increasing the carbon-hydrogen ratio in the gas, such as increasing the carbon-hydrogen ratio to 4-5%; and increasing the boron-carbon ratio, such as increasing the boron-carbon ratio to 2-5%; or using PVD to deposit a diamond-like layer. Although these methods introduce an sp2 hybrid surface layer, the increase in sp2 is based on the increase in the amorphous graphite layer. This amorphous graphite layer is not stable enough, which can easily cause the surface layer or even the entire coating to fall off quickly, affecting the stability during operation. Summary of the invention

[0005] The present application aims to solve one of the technical problems in the related art at least to some extent.

[0006] To this end, one purpose of the present application is to propose a method for crystallization treatment of the surface of a boron-doped diamond electrode, which can uniformly deposit crystalline fullerene C60 on the surface of the boron-doped diamond electrode. Crystalline fullerene 60 has the characteristics of sp2 hybridization, which not only increases the occurrence rate of adsorbed oxygen free radicals and promotes the occurrence of ozone, but also is not easy to fall off due to its strong adhesion, thereby ensuring higher stability.

[0007] To achieve the above-mentioned purpose, the first embodiment of the present application proposes a method for crystallizing the surface of a boron-doped diamond electrode, comprising: obtaining a boron-doped diamond electrode and fullerene C60 respectively; placing the boron-doped diamond electrode on a stage of an electron beam vacuum evaporator, and placing the fullerene C60 in a crucible of the electron beam vacuum evaporator; controlling the electron beam vacuum evaporator to start with preset parameters to crystallize the surface of the boron-doped diamond electrode to generate a target boron-doped diamond electrode.

[0008] The surface crystallization treatment method of the boron-doped diamond electrode in the embodiment of the present application can uniformly deposit crystalline fullerene C60 on the surface of the boron-doped diamond electrode by deposition. The crystalline fullerene 60 has the characteristics of sp2 hybridization, which not only increases the occurrence rate of adsorbed oxygen free radicals and promotes the occurrence of ozone, but also is not easy to fall off due to its strong adhesion, thereby ensuring higher stability.

[0009] In addition, the surface crystallization treatment method of the boron-doped diamond electrode proposed in the present application may also have the following additional technical features:

[0010] In one embodiment of the present application, the preset parameters include the vacuum pressure being 1*10 -5 ~5*10 -5 Pa, and the evaporation temperature is between 800 and 1000 degrees.

[0011] In one embodiment of the present application, the purity of the fullerene C60 is 99.5%.

[0012] In one embodiment of the present application, the deposition thickness of the fullerene C60 is between 4.2 and 10.4 nanometers, and the deposition time is between 3 and 15 seconds.

[0013] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become apparent from the description below, or will be learned through the practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] The above and / or additional aspects and advantages of the present application will become apparent and easily understood from the following description of the embodiments in conjunction with the accompanying drawings, in which:

[0015] Figure 1 A schematic diagram of a process for treating a surface of a boron-doped diamond electrode for crystallization according to an embodiment of the present application;

[0016] Figure 2 The C1s photoelectron spectrum of the evaporation sequence of fullerene C60 on boron-doped diamond is shown as an example of the present application. DETAILED DESCRIPTION

[0017] Embodiments of the present application are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements with the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present application, and should not be construed as limitations on the present application. On the contrary, the embodiments of the present application include all changes, modifications and equivalents that fall within the spirit and connotation of the appended claims.

[0018] The following describes the surface crystallization treatment method of a boron-doped diamond electrode according to an embodiment of the present application in conjunction with the accompanying drawings.

[0019] The surface crystallization treatment method of a boron-doped diamond electrode provided in the embodiment of the present application can be applied to the field of ozone preparation, and is mainly used for boron-doped diamond electrodes deposited by various materials and methods. By depositing a uniform layer of fullerene C60 on the surface of the boron-doped diamond electrode, not only the energy efficiency of ozone preparation is improved, but also the ozone is more stable and not easy to fall off.

[0020] like Figure 1 As shown, the surface crystallization treatment method of the boron-doped diamond electrode in the embodiment of the present application may include:

[0021] Step 101, respectively obtain a boron-doped diamond electrode and fullerene C60.

[0022] It should be noted that the fullerene C60 described in this embodiment can be purchased directly from the market, wherein the purity of the fullerene C60 is 99.5%, and the boron-doped diamond electrode can be prepared by chemical vapor deposition.

[0023] Step 102, placing a boron-doped diamond electrode on a stage of an electron beam vacuum evaporator, and placing fullerene C60 in a crucible of the electron beam vacuum evaporator.

[0024] It should be noted that the stage described in this embodiment is arranged on the upper inner wall of the electron beam vacuum evaporator, a plurality of boron-doped diamond electrodes can be installed on the stage, the crucible is arranged on the lower inner wall of the electron beam vacuum evaporator, and an electron gun is provided inside the electron beam vacuum evaporator, through which electrons can be emitted, and the electrons enter the crucible through the action of the magnetic field and heat the fullerene C60 in the crucible to evaporate the fullerene C60.

[0025] Furthermore, the electron beam vacuum evaporator is connected to a vacuum pump, and the electron beam vacuum evaporator can be evacuated by the vacuum pump to ensure that the fullerene C60 is in a clean, dry, and impurity-free environment. At the same time, in a vacuum environment, the boiling point of the fullerene C60 will be lowered, making it easier to evaporate.

[0026] Step 103, controlling the electron beam vacuum evaporator to start with preset parameters to perform a crystallization process on the surface of the boron-doped diamond electrode to generate a target boron-doped diamond electrode.

[0027] In an embodiment of the present application, when the electron beam vacuum evaporator is started with preset parameters, the fullerene C60 can be heated and evaporated. At this time, the evaporated fullerene C60 rises and deposits on the surface of the boron-doped diamond electrode, thereby generating a target boron-doped diamond electrode.

[0028] Furthermore, the preset parameters include the vacuum pressure being 1*10 -5 ~5*10 -5 Pa, and the evaporation temperature is between 800 and 1000 degrees.

[0029] It should be noted that at normal temperature and pressure, the boiling point of fullerene C60 is 500-600 degrees. Under a vacuum environment, the boiling point of fullerene C60 will decrease. Controlling the temperature between 800 and 1000 degrees can ensure that fullerene C60 evaporates completely.

[0030] In one embodiment of the present application, the deposition thickness of fullerene C60 is between 4.2 and 10.4 nanometers, and the deposition time is between 3 and 15 seconds.

[0031] It should be noted that the deposition thickness of fullerene C60 increases with the increase of deposition time, and the two are in direct proportion, that is, the longer the deposition time, the thicker the deposited fullerene C60. The specific deposition thickness can be selected according to actual needs.

[0032] Specifically, when depositing fullerene C60 on the surface of the boron-doped diamond electrode, the relevant personnel placed the prepared fullerene C60 in a crucible and installed multiple boron-doped diamond electrodes on the stage. Then, the vacuum pressure and evaporation temperature in the electron beam vacuum evaporator were adjusted to ensure that the vacuum pressure was within 1*10 -5 ~5*10 -5 Pa, the evaporation temperature is between 800 and 1000 degrees, and the evaporation temperature can be reached in about 5 minutes. Then the fullerene C60 evaporates and rises, and is deposited on the surface of the boron-doped diamond electrode above. The deposition takes about 15 seconds. After the deposition is completed, the boron-doped diamond electrode can be taken out after cooling to room temperature. At this time, a boron-doped diamond electrode with deposited fullerene C60 crystals can be generated.

[0033] It should be noted that because both fullerene C60 and diamond are composed entirely of carbon, when fullerene C60 is vapor deposited onto a diamond surface, the only expected major energy level signal in the photoemission spectrum is the signal corresponding to the 1s level electron emission of carbon (C1s). Therefore, X-ray photoelectron spectroscopy (XPS) combined with photoelectron spectroscopy (PES) can detect fullerene C60 only when the C1s peaks of the two materials have different binding energies, see Figure 2 , after the sample was introduced and heated, only the diamond signal was detected at 284.2 eV. In addition to the 1.25 eV binding energy difference between the sp 3 hybridized carbon atoms of diamond and the sp 2 hybridized carbon atoms of C60, the thickness of the C60 layer can be quantitatively evaluated. To this end, the individual spectral components were adjusted to lines consisting of Lorentzian and Gaussian profile folding according to the method of least quadratic deviation. The relationship between the spectral intensity and the thickness of the fullerene C60 was established in combination with the film thickness measurement of PES.

[0034] This application takes different embodiments as examples and conducts parallel tests on similar products introduced into the market at the same time, that is, the performance tests of the BDD electrodes used for producing ozone in the embodiments and comparative examples are conducted, as follows:

[0035] (1) Life test

[0036] Prepare 1 mol / L sulfuric acid and 1 mol / L hydrochloric acid, and mix with sodium sulfate solution to increase conductivity. Use jacket cooling device to keep the temperature at room temperature and keep the temperature at 1A / cm 2 The life test was carried out under the current density of , and the failure was judged by the voltage exceeding 50% of the initial value. The test results are as follows:

[0037] Table 1

[0038]

[0039] Referring to Table 1, the service life of the boron-doped diamond electrode after depositing fullerene C60 is longer, which is twice the service life of the boron-doped diamond electrode without fullerene C60.

[0040] (2) Ozone water concentration test after fullerene C60 deposition using boron-doped diamond electrode

[0041] The ozone yield of the electrode was detected by an ultraviolet spectrophotometer. 2 mL of water sample was taken, and the indicator (DPD, N, N-diethyl-p-phenylenediamine) was added and shaken. After mixing evenly, it was allowed to stand for 30 minutes to fully react. Finally, the absorbance at a wavelength of 510 nm was detected by ultraviolet light to characterize its ozone concentration. The ozone yield results of the electrode are shown in Table 2.

[0042] Table 2

[0043]

[0044] Referring to Table 2, the concentration of ozone water prepared by the boron-doped diamond electrode after depositing fullerene C60 is significantly higher than that of the boron-doped diamond electrode without fullerene C60. It can be seen that the deposition of fullerene C60 helps to increase the occurrence rate of ozone. Furthermore, the thickness of the fullerene C60 crystal deposition is proportional to the concentration of ozone prepared, that is, the thicker the deposition, the higher the ozone concentration.

[0045] In summary, the surface crystallization treatment method of the boron-doped diamond electrode in the embodiment of the present application can uniformly deposit crystalline fullerene C60 on the surface of the boron-doped diamond electrode by deposition. The crystalline fullerene 60 has the characteristics of sp2 hybridization, which not only increases the occurrence rate of adsorbed oxygen free radicals and promotes the occurrence rate of ozone, but also is not easy to fall off due to its strong adhesion, thereby ensuring higher stability.

[0046] In the description of this specification, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of this application, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0047] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0048] Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limitations on the present application. Ordinary technicians in this field can change, modify, replace and deform the above embodiments within the scope of the present application.

Claims

1. A method for treating the surface of a boron-doped diamond electrode for crystallization, characterized in that: include Obtain boron-doped diamond electrode and fullerene C60 respectively; Placing the boron-doped diamond electrode on a stage of an electron beam vacuum evaporator, and placing the fullerene C60 in a crucible of the electron beam vacuum evaporator; The electron beam vacuum evaporator is controlled to start with preset parameters to perform a crystallization process on the surface of the boron-doped diamond electrode to generate a target boron-doped diamond electrode.

2. The method for crystallizing the surface of a boron-doped diamond electrode according to claim 1, characterized in that: The preset parameters include the vacuum pressure being 1*10 -5 ~5*10 -5 Pa, and the evaporation temperature is between 800 and 1000 degrees.

3. The method for treating the surface of a boron-doped diamond electrode according to claim 1, characterized in that: The purity of the fullerene C60 is 99.5%.

4. The method for treating the surface of a boron-doped diamond electrode according to claim 1, characterized in that: The deposition thickness of the fullerene C60 is between 4.2 and 10.4 nanometers, and the deposition time is between 3 and 15 seconds.

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