Electro-catalytic hydrogen evolution electrode with multi-level pore channel structure and preparation method and application thereof
阅读说明：本技术 一种多级孔道结构的电催化析氢电极及其制备方法和应用 (Electro-catalytic hydrogen evolution electrode with multi-level pore channel structure and preparation method and application thereof ) 是由 江雷 田野 陈凤翔 朱忠鹏 徐哲 于 2020-05-26 设计创作，主要内容包括：本发明公开一种多级孔道结构的电催化析氢电极,包括具有多级孔道结构的催化剂层以及具有微纳结构的基底层；催化剂层在整个电极中的负载量为0.001-0.05g/cm～(2)；其中,催化剂层的厚度为0.2-1000nm,孔道直径为0.1-100nm,孔隙率为5-90％,比表面积为100-1800m～(2)/g。该电极的催化剂层孔隙率高、比表面积大,能够提供的活性位点多,催化活性高；同时催化剂的载量少、厚度小,表面张力低,使析氢过程中电极表面产生的气泡能够快速从电极析出,进一步提高了催化活性。化学键原位生长的制备过程也使催化剂层具有优异的环境服役性和超长的使用寿命。(Hair brushThe invention discloses an electrocatalytic hydrogen evolution electrode with a multistage pore channel structure, which comprises a catalyst layer with the multistage pore channel structure and a substrate layer with a micro-nano structure; the loading amount of the catalyst layer in the whole electrode is 0.001-0.05g/cm 2 (ii) a Wherein the thickness of the catalyst layer is 0.2-1000nm, the pore diameter is 0.1-100nm, the porosity is 5-90%, and the specific surface area is 100-1800m 2 (ii) in terms of/g. The catalyst layer of the electrode has high porosity, large specific surface area, more active sites and high catalytic activity; meanwhile, the catalyst has the advantages of small loading capacity, small thickness and low surface tension, so that bubbles generated on the surface of the electrode in the hydrogen evolution process can be rapidly separated out from the electrode, and the catalytic activity is further improved. The preparation process of chemical bond in-situ growth also enables the catalyst layer to have excellent environmental serviceability and ultra-long service life.)
1. An electrocatalytic hydrogen evolution electrode with a hierarchical pore structure is characterized by comprising a catalyst layer with the hierarchical pore structure and a substrate layer with a micro-nano structure; the loading amount of the catalyst layer in the whole electrode is 0.001-0.5g/cm2(ii) a Wherein the thickness of the catalyst layer is 0.2-1000nm, the pore diameter is 0.1-100nm, the porosity is 5-90%, and the specific surface area is 100-1800m2/g。
2. The multi-level pore structured electrocatalytic hydrogen evolution electrode according to claim 1, wherein the catalyst layer is generated in situ by chemical bonding on the base layer by a multi-pulse gas-phase permeation method; preferably, the surface tension of the catalyst layer is 0-50 μ N and the contact angle of the gas bubbles on the electrode surface is > 150 °.
3. The electrocatalytic hydrogen evolution electrode with a hierarchical pore structure according to claim 1, wherein the catalyst layer is a metal-based nano-film, a metal oxide-based nano-film or an alloy nano-film; preferably, the catalyst layer is a Pt-based nano-film and an alloy nano-film of Pt and Co, Ir, Pd, W, Ni, Fe, Cu, respectively.
4. The multi-channel structured electrocatalytic hydrogen evolution electrode according to claim 1, wherein the substrate layer has a contact angle with water < 5 °; preferably, the surface of the substrate layer contains a plurality of oxygen-containing groups selected from at least one of-COOH, -OH and lactone groups.
5. The electrocatalytic hydrogen evolution electrode with the hierarchical pore channel structure according to claim 1, wherein the micro-nano structure of the substrate layer refers to a nanowire array structure, a framework network structure and a foam structure.
6. The multi-level pore structured electrocatalytic hydrogen evolution electrode of claim 1, wherein the base layer is a metal nanowire array, a metal foam, a semiconductor-based nanowire array, a semiconductor foam, or a non-metal-based foam.
7. A method for preparing an electrocatalytic hydrogen evolution electrode with a hierarchical cell structure according to any one of claims 1 to 6, comprising the steps of:
(1) placing the pretreated substrate into a reaction cavity of multi-pulse gas-phase permeation equipment with the temperature of 60-300 ℃, and purging with high-purity nitrogen with the purity of 99.999% for 25-30min, wherein the flow rate of the nitrogen is 50-100 sccm;
(2) heating the metal source of the catalyst layer to 60-120 ℃, and pumping the metal source into the reaction cavity in a pulse mode; performing nitrogen purging for the first time, pumping an oxygen source into the reaction cavity in a pulse mode, and performing nitrogen purging for the second time to finish a deposition cycle;
(3) the deposition cycle is repeated 2-10000 times.
8. The method for preparing the electrocatalytic hydrogen evolution electrode with the multilevel pore channel structure according to claim 7, wherein when the metal source of the catalyst layer in the step (2) is pumped into the reaction cavity in a pulse mode, the pulse time is 0.1-1s, and the exposure time is 5-30 s; preferably, when the oxygen source is pumped into the reaction cavity in a pulse mode in the step (2), the pulse time is 0.05-1s, and the exposure time is 8-20 s; preferably, the purity of the nitrogen used for nitrogen purging in the step (2) is 99.999%, and the flow rate of the nitrogen is 50-80 sccm; the first nitrogen purging time is 10-35s, and the second nitrogen purging time is 15-30 s.
9. The method for preparing an electrocatalytic hydrogen evolution electrode with a hierarchical pore structure as set forth in claim 7, wherein the thickness of the catalyst layer increased by one deposition cycle is 0.082-0.12 nm.
10. Use of an electrocatalytic hydrogen evolution electrode with a hierarchical cell structure according to any of claims 1-6 for electrocatalytic hydrogen evolution.
Technical Field
The invention relates to the technical field of electrocatalytic hydrogen evolution. More particularly, relates to an electrocatalytic hydrogen evolution electrode with a multi-level pore channel structure, and a preparation method and application thereof.
Background
With the further consumption of fossil energy, the development of alternative new energy is imminent. As hydrogen energy which has higher combustion value, is clean and pollution-free and can be recycled, the hydrogen energy is more and more concerned by the majority of researchers. Although there are many methods for producing hydrogen, there are still many problems in the development process, such as high requirement for production equipment, high energy consumption in the production process, complex process required for production, impure obtained product, etc. Therefore, it is imperative to develop a hydrogen evolution method with low energy consumption and high efficiency. The hydrogen production by water electrolysis is an important means for realizing the industrial and cheap hydrogen preparation, but the technology has the biggest problem of high electric energy consumption and higher production cost. The main reason of large power consumption is the over-high hydrogen evolution potential of the electrolysis electrode, so it is important to reduce the electrolysis energy consumption by reducing the over-potential of hydrogen evolution.
The catalytic activity of the hydrogen evolution catalyst reported at present is best with a platinum catalyst, but the crust storage capacity is low and the price is high. Therefore, the research on the existing hydrogen evolution Pt catalyst has mainly focused on how to reduce the Pt loading amount. The specific surface area of Pt is increased, so that Pt with the same mass is exposed to more catalytic active sites, for example, a monoatomic layer, a nanowire, a nanoparticle or a nanocluster, or even a monoatomic catalyst is prepared from Pt; (2) further increasing the catalytic activity of the Pt-containing catalyst, such as the formation of metal alloys or metal-nonmetal complexes with other metals and metalloids. The two paths are most typically represented by a commercial Pt/C hydrogen evolution catalyst, but the catalyst needs a specific binder such as Nafion solution for preparing an electrode, the use of the binder impairs the catalytic activity and stability of the catalyst, but the hydrogen evolution activity of preparing a binderless Pt-containing catalyst directly on an electrode substrate is very low, and thus the commercial requirement is very difficult to meet.
Disclosure of Invention
The invention aims to provide an electrocatalytic hydrogen evolution electrode with a multi-stage pore channel structure, wherein a catalyst in the electrode has the multi-stage pore channel structure, high porosity, large specific surface area, a plurality of active sites and high catalytic activity; meanwhile, the catalyst has small loading capacity and low surface tension, so that bubbles generated on the surface of the electrode in the hydrogen evolution process can be rapidly separated out from the electrode.
The second purpose of the invention is to provide a preparation method of the electrocatalytic hydrogen evolution electrode with the multi-stage pore channel structure.
The third purpose of the invention is to provide the application of the electrocatalytic hydrogen evolution electrode with the multi-stage pore channel structure.
In order to achieve the purpose, the invention adopts the following technical scheme:
in a first aspect, the invention provides an electrocatalytic hydrogen evolution electrode with a hierarchical pore channel structure, which comprises a catalyst layer with a hierarchical pore channel structure and a substrate layer with a micro-nano structure; the loading amount of the catalyst layer in the whole electrode is 0.001-0.5g/cm2(ii) a Wherein the thickness of the catalyst layer is 0.2-1000nm, the pore diameter is 0.1-100nm, the porosity is 5-90%, and the specific surface area is 100-1800m2/g。
Optionally, the catalyst layer is generated in situ by chemical bonding on the substrate layer by a multi-pulse gas phase infiltration process.
The catalyst layer is formed on the substrate layer by chemical method through multi-pulse gas-phase permeation methodThe bond is generated in situ, the catalyst layer can stably maintain the micro-nano structure on the substrate layer, the thickness of the catalyst layer formed by one deposition cycle of the multi-pulse gas-phase permeation method is only 0.082-0.12nm, the thickness of the obtained catalyst layer can be effectively controlled by controlling the deposition cycle number, the catalyst layer with the nano-scale thickness is obtained, and the loading capacity is only 0.001-0.5g/cm2. Through the formation process of in-situ growth of chemical bonds, a binder such as a Nafion solution is not needed in the preparation process of the electrode, so that the damage of the binder to the catalytic activity and stability of a catalyst layer is avoided; meanwhile, the generated catalyst layer also has excellent environmental serviceability and ultra-long service life.
The preparation cycle times of the catalyst layer prepared by the multi-pulse gas-phase permeation method can be controlled to be 2-10 times, so that the monatomic catalyst is obtained, and the monatomic catalyst is uniformly distributed on the surface of the substrate layer with the micro-nano structure.
The catalyst layer can stably maintain the micro-nano structure on the substrate to form a multi-stage pore channel structure, has high porosity and specific surface area, can expose more active sites, and enables the catalyst layer with low loading capacity to still have excellent catalytic activity.
Optionally, the surface tension of the catalyst layer is 0-50 μ N and the contact angle of the gas bubbles on the electrode surface is > 150 °. Because the surface tension of the catalyst layer is low, the catalyst layer is in a super-gas-dredging state, bubbles generated in the hydrogen production process by electrolysis can be quickly separated, and the electrode activity is greatly improved.
Optionally, the catalyst layer is a metal-based nano-film, a metal oxide-based nano-film or an alloy nano-film; preferably, the Pt-based nano-film and the Pt alloy nano-film are Co, Ir, Pd, W, Ni, Fe and Cu, respectively.
The surface of the substrate layer with the micro-nano structure has a large number of hydrophilic oxygen-containing groups, the contact angle of the substrate layer with water is less than 5 degrees, and the surface of the substrate layer contains a large number of oxygen-containing groups including but not limited to at least one of-COOH, -OH and lactone groups; the method is favorable for inducing the catalyst layer to grow rapidly and uniformly, and the stable morphology can be kept in the growth process. Preferably, the micro-nano structure of the substrate layer refers to a nanowire array structure, a framework network structure and a foam structure, and when the catalyst layer is generated in situ on the substrate layer through chemical bonds by a multi-pulse gas-phase permeation method, the catalyst layer can form a structure similar to the micro-nano structure on the substrate layer, namely a multi-level pore channel structure. Preferably, the base layer is a metal nanowire array, a metal foam, a semiconductor-based nanowire array, a semiconductor foam, or a non-metal-based foam, including but not limited to silicon-based nanowire arrays, silver-based nanowire arrays, nickel-based foams.
In a second aspect, the invention provides a preparation method of an electrocatalytic hydrogen evolution electrode with a multi-level pore channel structure, which comprises the following steps:
(1) placing the pretreated substrate into a reaction cavity of multi-pulse gas-phase permeation equipment with the temperature of 60-300 ℃, and purging with high-purity nitrogen with the purity of 99.999% for 25-30min, wherein the flow rate of the nitrogen is 50-100 sccm;
(2) heating the metal source of the catalyst layer to 60-120 ℃, and pumping the metal source into the reaction cavity in a pulse mode; performing nitrogen purging for the first time, pumping an oxygen source into the reaction cavity in a pulse mode, and then performing nitrogen purging for the second time to finish a deposition cycle;
(3) the deposition cycle is repeated 2-10000 times.
If the catalyst layer is an alloy nano film, the step (2) can be repeated by selecting different metal sources in the preparation process to obtain the catalyst layer of the alloy nano film.
The pretreatment process of the substrate is soaking the piranha solution for 10-60 minutes or (oxygen/air) plasma treating for 5-30 minutes.
Optionally, when the metal source of the catalyst layer in step (2) is pumped into the reaction chamber in a pulse form, the pulse time is 0.1-1s, and the exposure time is 5-30 s.
Optionally, in step (2), when the oxygen source is pumped into the reaction chamber in a pulsed manner, the pulse time is 0.05-1s, and the exposure time is 8-20 s.
Optionally, the purity of the nitrogen used for nitrogen purging in the step (2) is 99.999%, and the flow rate of the nitrogen is 50-80 sccm; the first nitrogen purging time is 10-35s, and the second nitrogen purging time is 15-30 s.
Alternatively, the catalyst layer thickness is increased by one deposition cycle from 0.082 to 0.12 nm. In the preparation of the catalyst layer, a catalyst layer of a specific thickness can be obtained by controlling the number of deposition cycles.
The invention also provides a preparation process of the vertical silicon-based nanowire arrays with different lengths as the substrate layer, which comprises the following steps:
(a) immersing a monocrystalline silicon wafer into an organic solvent for 10-20 minutes of ultrasound, and then immersing into deionized water for 10-20 minutes of ultrasound;
(b) immersing the silicon wafer subjected to ultrasonic treatment into an acid solution with strong oxidizing property, and reacting for 1-2 hours at the temperature of 100-200 ℃ to obtain a super-hydrophilized monocrystalline silicon wafer; the acid solution with strong oxidizing property is a composite solution consisting of a sulfuric acid solution with the mass concentration of 60-98% and a hydrogen peroxide solution with the mass concentration of 30-36%, wherein the volume ratio of the hydrogen peroxide solution to the concentrated sulfuric acid solution is 1: 4-3: 7;
(c) placing the single crystal silicon wafer subjected to super-hydrophilization treatment in a hydrofluoric acid solution with the mass concentration of 5% -10% for reaction for 3-5 min;
(d) placing the monocrystalline silicon wafer treated by the hydrofluoric acid solution in a silver nitrate and hydrofluoric acid composite solution for reacting for 2-5 minutes, and cleaning, wherein the mass concentration of hydrofluoric acid is 3-6mol/L, and the concentration of silver nitrate is 0.001-0.01 mol/L;
(e) placing the monocrystalline silicon wafer treated in the step (d) in a composite solution of hydrofluoric acid and hydrogen peroxide for reacting for 2-60 minutes, and cleaning, wherein the mass concentration of the hydrofluoric acid is 3-6mol/L, and the concentration of the hydrogen peroxide is 0.1-0.8 mol/L;
(f) and (e) placing the monocrystalline silicon wafer treated in the step (e) into a nitric acid solution with the volume concentration of 25-80% for treatment for 1-5 hours, and obtaining the silicon nanowire arrays with different lengths.
Fig. 1 shows a process for preparing an electrocatalytic hydrogen evolution electrode of a nanowire array-platinum-based nano-film.
The third aspect of the invention also provides the application of the electrocatalytic hydrogen evolution electrode with the multi-stage pore channel structure in electrocatalytic hydrogen evolution.
The catalyst layer of the electrocatalytic hydrogen evolution electrode with the multi-stage pore channel structure has the multi-stage pore channel structure, high porosity, large specific surface area, more active sites and high catalytic activity; meanwhile, the catalyst has small loading capacity and low surface tension, so that bubbles generated on the surface of the electrode in the hydrogen evolution process can be rapidly separated out from the electrode.
The invention has the following beneficial effects:
the invention provides an electrocatalytic hydrogen evolution electrode with a multistage pore channel structure, which comprises a catalyst layer with a multistage pore channel structure and a substrate layer with a micro-nano structure, wherein the catalyst layer is generated in situ on the substrate layer through chemical bonds by a multi-pulse gas-phase permeation method. Therefore, the catalyst layer has high porosity, large specific surface area, more active sites and high catalytic activity; meanwhile, the catalyst has the advantages of small loading capacity, small thickness and low surface tension, so that bubbles generated on the surface of the electrode in the hydrogen evolution process can be rapidly separated out from the electrode, and the catalytic activity is further improved. The preparation process of chemical bond in-situ growth also enables the catalyst layer to have excellent environmental serviceability and ultra-long service life.
Drawings
In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed to be used in the description of the embodiments will be briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without creative efforts.
Fig. 1 shows the preparation process of an electrocatalytic hydrogen evolution electrode of nanowire array-platinum-based nanofilm.
FIG. 2 shows the hydrogen evolution voltage for a commercial 5% Pt-C electrode, a 20% Pt-C electrode and a high purity Pt flake electrode (Pt wafer) and the electrocatalytic hydrogen evolution electrode prepared in example 1 (Si NW-50C Pt).
FIG. 3 shows the Tafel slopes of a commercial 5% Pt-C electrode, a 20% Pt-C electrode, and a high purity Pt flake electrode (Pt wafer) and an electrocatalytic hydrogen evolution electrode (Si NW-50C Pt) prepared in example 1.
Detailed Description
In order to make the technical solutions and advantages of the present invention more apparent, embodiments of the present invention will be described in detail with reference to the accompanying drawings.
Examples
Example 1
Electrocatalytic hydrogen evolution electrode of silicon-based nanowire array-platinum-based nano film
And preparing the vertical silicon-based nanowire array with different lengths by adopting a metal-assisted chemical corrosion method. And then soaking the prepared silicon nanowire arrays with different lengths in the piranha solution for 30min, taking out, and drying at low temperature.
And (3) placing the vertical silicon-based nanowire treated by the piranha into a reaction cavity of a multi-pulse gas-phase permeation device at the temperature of 270 ℃, and purging with high-purity nitrogen with the purity of 99.999% for 25-30min, wherein the flow rate of the nitrogen is 50-100 sccm. Heating the Pt source to 80 ℃, pumping the Pt source into the reaction cavity in a pulse mode, wherein the pulse time is 0.5s, enabling the Pt source gas to act on the substrate material in the cavity for 25s, then purging the cavity by nitrogen, and purging the redundant unreacted Pt source out of the cavity. And pumping an oxygen source into the reaction cavity in a pulse mode, wherein the pulse time is 0.5s, enabling oxygen source gas to act with the substrate material in the cavity for 20s, and then purging with nitrogen to purge redundant unreacted oxygen source out of the cavity. Repeating the above circulation for 2000 circulations to obtain the electro-catalytic hydrogen evolution electrode with the silicon nanowire as the substrate and the ultrathin Pt film as the catalyst layer. The loading amount of the hydrogen evolution electrode catalyst layer in the whole electrode is 0.108g/cm2(ii) a Wherein the thickness of the catalyst layer is about 196nm, the diameter of the pore channel is 15-100nm, the porosity is 12-40%, and the specific surface area is 480m2And the contact angle of the bubbles on the surface of the electrode is 175 degrees, and the Tafel slope of the bubbles is 31.15mv/dec.
As shown in fig. 2, the electrocatalytic hydrogen evolution electrode (Si NW-50C Pt) of the Si-based nanowire array-Pt-based nano thin film prepared in example 1 showed an extremely low hydrogen evolution voltage, which is far superior to the commercial 5% Pt-C electrode, 20% Pt-C electrode and high purity Pt sheet electrode (Pt wafer).
As shown in fig. 3, the electrocatalytic hydrogen evolution electrode (Si NW-50C Pt) of the silicon-based nanowire array-platinum-based nano thin film prepared in example 1 showed a smaller Tafel slope, which is lower than that of the commercial 5% Pt-C electrode, 20% Pt-C electrode and high-purity Pt sheet electrode (Pt wafer).
Example 2
Electrocatalytic hydrogen evolution electrode of silicon-based nanowire array-platinum-iron alloy nano film
And preparing the vertical silicon-based nanowire array with different lengths by adopting a metal-assisted chemical corrosion method. And then soaking the prepared silicon nanowire arrays with different lengths in the piranha solution for 30min, taking out, and drying at low temperature.
And (3) placing the vertical silicon-based nanowire treated by the piranha into a reaction cavity of a multi-pulse gas-phase permeation device at the temperature of 180 ℃, and purging with high-purity nitrogen with the purity of 99.999% for 25-30min, wherein the flow rate of the nitrogen is 50-100 sccm. Heating an iron source to 100 ℃, pumping the iron source into the reaction cavity in a pulse mode, wherein the pulse time is 1s, enabling the iron source gas to act on the substrate material in the cavity for 30s, then purging by nitrogen, and purging the excess unreacted iron source out of the cavity. And pumping an oxygen source into the reaction cavity in a pulse mode, wherein the pulse time is 1s, enabling oxygen source gas to act on the substrate material in the cavity for 15s, and then purging with nitrogen to purge redundant unreacted oxygen source out of the cavity. Repeating the above circulation for 2000 circulations to obtain the electro-catalytic hydrogen evolution electrode with the silicon nanowire as the substrate and the ultrathin iron film as the catalyst layer.
And then placing the iron-based electrocatalytic hydrogen evolution electrode in a tubular furnace with 5% hydrogen and argon atmosphere, and reducing for 2h at 450 ℃.
And placing the reduced iron-based electrode into a reaction cavity of a multi-pulse gas phase permeation device at the temperature of 270 ℃, and purging with high-purity nitrogen with the purity of 99.999% for 25-30min, wherein the flow rate of the nitrogen is 50-100 sccm. Heating the Pt source to 80 ℃, pumping the Pt source into the reaction cavity in a pulse mode, wherein the pulse time is 0.5s, enabling the Pt source gas to act on the substrate material in the cavity for 25s, then purging the cavity by nitrogen, and purging the redundant unreacted Pt source out of the cavity. Then pumping the oxygen source into the reaction chamber in a pulse mode, wherein the pulse time is 0.5s, and thenAnd enabling the oxygen source gas to act on the substrate material in the cavity for 20s, and then purging with nitrogen to purge the redundant unreacted oxygen source out of the cavity. And repeating the circulation for 5 cycles to prepare the electrocatalytic hydrogen evolution electrode with the catalyst layer which takes the silicon nanowire as the substrate, the ultrathin iron film as the conductive layer and Pt monoatomic atoms uniformly dispersed on the surface of the iron-based film. The loading amount of the hydrogen evolution electrode catalyst layer in the whole electrode is 0.13g/cm2(ii) a Wherein the thickness of the catalyst layer is about 212nm, the diameter of the pore channel is 18-100nm, the porosity is 12-40%, and the specific surface area is 370m2And the contact angle of the bubbles on the surface of the electrode is 158 degrees, and the Tafel slope of the bubbles is 52.13mv/dec.
Example 3
Silver-based nanowire array-platinum-based nano-film electro-catalysis hydrogen evolution electrode
And (3) carrying out ultrasonic treatment on the silver nanowire array in an absolute ethyl alcohol solution for 60min, then taking out, and airing at low temperature.
And placing the cleaned silver nanowires into a reaction cavity of a multi-pulse gas-phase permeation device at the temperature of 270 ℃, and purging with high-purity nitrogen with the purity of 99.999% for 25-30min, wherein the flow rate of the nitrogen is 50-100 sccm. Heating the Pt source to 80 ℃, pumping the Pt source into the reaction cavity in a pulse mode, wherein the pulse time is 0.5s, enabling the Pt source gas to act on the substrate material in the cavity for 25s, then purging the cavity by nitrogen, and purging the redundant unreacted Pt source out of the cavity. And pumping an oxygen source into the reaction cavity in a pulse mode, wherein the pulse time is 0.5s, enabling oxygen source gas to act with the substrate material in the cavity for 20s, and then purging with nitrogen to purge redundant unreacted oxygen source out of the cavity. And repeating the circulation for 20 cycles to prepare the electro-catalytic hydrogen evolution electrode which takes the silver nanowire as the substrate and Pt monoatomic atoms uniformly dispersed on the surface of the silver nanowire as the catalyst layer. The prepared hydrogen evolution electrode was then etched in a plasma for 15 minutes. The loading amount of the hydrogen evolution electrode catalyst layer in the whole electrode is less than 0.001g/cm2(ii) a Wherein the thickness of the catalyst layer is about 1.8nm, the diameter of the pore channel is 85nm, the porosity is 32 percent, and the specific surface area is 240m2The contact angle of the bubble on the electrode surface is 163 degrees, and the Tafel slope is 36.56mv/dec.
Example 4
Nickel foam-electrocatalytic hydrogen evolution electrode of platinum-based nano-film: and (3) carrying out ultrasonic treatment on the commercial nickel foam material in absolute ethyl alcohol for 90min, then taking out, and airing at low temperature. And placing the cleaned nickel foam material into a reaction cavity of a multi-pulse gas-phase permeation device at the temperature of 270 ℃, and purging with high-purity nitrogen with the purity of 99.999% for 25-30min, wherein the flow rate of the nitrogen is 50-100 sccm. Heating the Pt source to 80 ℃, pumping the Pt source into the reaction cavity in a pulse mode, wherein the pulse time is 0.5s, enabling the Pt source gas to act on the substrate material in the cavity for 25s, then purging the cavity by nitrogen, and purging the redundant unreacted Pt source out of the cavity. And pumping an oxygen source into the reaction cavity in a pulse mode, wherein the pulse time is 0.5s, enabling oxygen source gas to act with the substrate material in the cavity for 20s, and then purging with nitrogen to purge redundant unreacted oxygen source out of the cavity. Repeating the circulation for 2-200 cycles to prepare the Pt monatomic cluster or high conformal Pt thin film electro-catalytic hydrogen evolution electrode with uniformly distributed nickel foam inside and outside. The prepared hydrogen evolution electrode was then etched in a plasma for 15 minutes. The loading capacity of the hydrogen evolution electrode catalyst layer in the whole electrode is 0-0.0065g/cm2(ii) a Wherein the thickness of the catalyst layer is about 0.16-22nm, the pore diameter is 40-100nm, the porosity is 12-40%, and the specific surface area is 600-800m2The contact angle of the air bubble on the surface of the electrode is 150-.
Example 5
Carbon foam material-platinum copper alloy nano film electrocatalytic hydrogen evolution electrode: and (3) carrying out ultrasonic treatment on the commercial carbon foam material in absolute ethyl alcohol for 10min, then taking out, and airing at low temperature. The cleaned carbon foam was then etched in the plasma for 10 minutes.
And then placing the treated carbon foam material into a reaction cavity of a multi-pulse gas phase permeation device with the temperature of 150 ℃, and purging with high-purity nitrogen with the purity of 99.999 percent for 25-30min, wherein the flow rate of the nitrogen is 50-100 sccm. Heating a copper source to 80 ℃, pumping the copper source into the reaction cavity in a pulse mode, wherein the pulse time is 0.8s, enabling the copper source gas to act on the substrate material in the cavity for 25s, then purging with nitrogen, and purging the redundant unreacted copper source out of the cavity. And then pumping an oxygen source into the reaction cavity in a pulse mode, wherein the pulse time is 1s, enabling oxygen source gas to act on the substrate material in the cavity for 12s, and then purging with nitrogen to purge redundant unreacted oxygen source out of the cavity. Repeating the above circulation for 500 cycles to prepare the electrocatalytic hydrogen evolution electrode with the carbon foam material as the substrate and the ultrathin copper film as the catalyst layer.
Then the copper-based electro-catalytic hydrogen evolution electrode is placed in a tubular furnace with 5 percent hydrogen and argon atmosphere and reduced for 2h at the temperature of 450 ℃.
And placing the reduced copper-based electrode into a reaction cavity of multi-pulse gas-phase permeation equipment with the temperature of 270 ℃, and purging with high-purity nitrogen with the purity of 99.999% for 25-30min, wherein the flow rate of the nitrogen is 50-100 sccm. Heating the Pt source to 80 ℃, pumping the Pt source into the reaction cavity in a pulse mode, wherein the pulse time is 0.5s, enabling the Pt source gas to act on the substrate material in the cavity for 25s, then purging the cavity by nitrogen, and purging the redundant unreacted Pt source out of the cavity. And pumping an oxygen source into the reaction cavity in a pulse mode, wherein the pulse time is 0.5s, enabling oxygen source gas to act with the substrate material in the cavity for 20s, and then purging with nitrogen to purge redundant unreacted oxygen source out of the cavity. Repeating the circulation for 5-100 times to prepare the electrocatalytic hydrogen evolution electrode which takes the carbon foam material as the substrate, the ultrathin copper film as the conducting layer and the Pt monoatomic or highly conformal Pt film uniformly dispersed on the surface of the copper-based film as the catalyst layer. The loading capacity of the hydrogen evolution electrode catalyst layer in the whole electrode is less than 0.2g/cm2(ii) a Wherein the thickness of the catalyst layer is about 48-60nm, the porosity is 20-60%, and the specific surface area is 1200-1650m2The contact angle of the bubbles on the surface of the electrode is 150 DEG-160 DEG, and the Tafel slope is 27.40-35.28 mv/dec.
It should be understood that the above-mentioned embodiments of the present invention are only examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention, and it will be obvious to those skilled in the art that other variations or modifications may be made on the basis of the above description, and all embodiments may not be exhaustive, and all obvious variations or modifications may be included within the scope of the present invention.