CN110711596A - Efficient full-hydrolysis water catalyst IPBAP/Ni2P@MoOx/NF and preparation method thereof - Google Patents

Abstract

The invention belongs to the field of new energy materials, and particularly relates to a high-efficiency total water splitting electrocatalyst IPBAP/Ni ₂ P@MoOx/NF and a preparation method thereof. The high-efficiency total water splitting electrocatalyst IPBAP/Ni ₂ P@MoOx/NF described in the present invention is to synthesize nano flower ball-shaped precursor by hydrothermal reaction with a certain proportion of ammonium molybdate and nickel nitrate; The composite material of in-situ Prussian blue analog phosphide, nickel phosphide, molybdenum oxide and nickel foam obtained by low-temperature phosphating after solution impregnation and loading. The catalyst combines the excellent hydrogen evolution performance of molybdenum oxide and the excellent oxygen evolution performance of Prussian blue analogs, and while maintaining the excellent hydrogen evolution performance, the oxygen evolution performance is greatly improved, and an electrocatalyst with efficient total water splitting performance is obtained. catalyst.

Description

An efficient electrocatalyst for total water splitting IPBAP/Ni2P@MoOx/NF and preparation method thereof

technical field

The invention belongs to the field of new energy materials, and particularly relates to a high-efficiency total water splitting electrocatalyst IPBAP/Ni ₂ P@MoOx/NF and a preparation method thereof.

Background technique

With the continuous advancement of social development and industrialization, the global energy demand has grown rapidly. At present, the problem of environmental pollution and the shortage of energy is an important factor for the urgent development of clean energy, and the development of a clean, efficient and sustainable new energy system is the fundamental way to solve the increasing energy crisis and environmental pollution in today's world. As a green and efficient secondary energy with a wide range of sources, hydrogen energy has the advantages of abundant resources, clean and efficient, high energy density, and environmental friendliness. It is an ideal renewable energy and will become an important energy system in the future. component. The preparation and utilization of hydrogen energy is crucial for alleviating energy and environmental problems, and has attracted extensive attention of researchers. Electrolyzed water and hydrogen-oxygen fuel cells have attracted much attention due to their unique advantages and application prospects in the preparation and utilization of hydrogen, and the application of electrolyzed water to hydrogen production is widely used to absorb the structural excess of renewable energy such as hydropower, wind power and photovoltaic power generation. Energy is an important way to optimize the energy consumption structure.

However, the hysteresis of electrocatalytic reactions such as oxygen evolution reaction, hydrogen evolution reaction and oxygen reduction reaction involved in the existing energy conversion devices such as water electrolysis and fuel cells is one of the important bottlenecks restricting their development, which causes this hysteresis. The reason is mainly due to the hysteresis of catalyst performance. Although traditional noble metal catalysts have good electrocatalytic performance, their high price and limited reserves hinder their large-scale commercial production and limit their development in the field of electrocatalysis. Therefore, the development of inexpensive, resource-rich and efficient non-precious metal catalysts to replace precious metal catalysts has become a hot research field. Among them, the total water splitting catalyst that can produce hydrogen and oxygen at the same time has received extensive attention.

Molybdenum-based catalyst is a new type of high-efficiency hydrogen evolution catalyst, which has excellent electrocatalytic hydrogen evolution performance under acidic, neutral and alkaline conditions, but the oxygen evolution performance of molybdenum-based catalyst is not excellent. Therefore, most of the current research focuses on how to improve the oxygen evolution performance of molybdenum-based catalysts. According to research, the composite can change the single characteristic of the material, which is a material with diverse properties. Therefore, many materials currently use the composite method to improve the electrocatalytic performance of the material.

Prussian blue analog (PBA) is a substance formed by the coordination interaction between the metal ion center and cyanide, and it has a variety of metal ions (such as Fe(CN) ₆ ^3- , Fe(CN) ₆ ^4- and Co(CN) ₆ ^3- ), giving PBA a versatile composition and controllable morphology. In addition, PBA can be thermally transformed into the corresponding oxides, selenides, phosphides, etc. through interesting and simple, making PBA derivatives have potential applications in electrocatalysis, energy conversion, and storage; meanwhile, combining PBA with some other The material composite can also significantly improve the electrocatalytic performance of the material. For example, after growing a layer of PBA on the surface of Ni(OH) ₂ by Xi et al., the performance of the phosphide generated is much improved compared with the phosphide that did not grow PBA before. Incorporation of Ni ₂ P can reduce the adsorption energy of O atoms, and the particles formed on the surface can greatly improve the active sites of the material, which are helpful to improve the oxygen evolution performance of the material (Xi W, Yan G, Lang et al. Z, et al. 2018. Oxygen-Doped Nickel IronPhosphide Nanocube Arrays Grown on Ni Foam for Oxygen Evolution Electrocatalysis. Small[J], 2018, 14:e1802204.). Another example is Ge etc. using hydrothermal to generate Ni(OH) ₂ precursor, and then hydrothermal reaction generates PBA, and then a composite product of Ni ₂ P and Fe ₃ P is synthesized. Due to the synergistic effect between Ni ₂ P and Fe ₃ P, the performance of this material has been greatly improved in hydrogen evolution (Y, Dong P, Craig SR, et al. Transforming Nickel Hydroxide into 3D Prussian Blue Analogue Array toObtain Ni ₂ P/ Fe ₂ P for Efficient Hydrogen Evolution Reaction. Advanced Energy Materials [J]: 2018, 1800484.).

It can be seen that studying the hydrogen evolution and oxygen evolution performance of materials on the basis of molybdenum-based catalysts is an urgent problem to be solved at present, and the catalyst of the present invention combines the excellent hydrogen evolution performance of molybdenum oxide and the excellent oxygen evolution performance of Prussian blue analogs, It is also very important to obtain electrocatalysts with efficient total water splitting performance, and to control the electronic structure and create ionic vacancies by ion doping, which is of great significance for the development of total water splitting electrocatalysts.

SUMMARY OF THE INVENTION

Therefore, the technical problem to be solved by the present invention is to provide a high-efficiency total water splitting electrocatalyst IPBAP/Ni ₂ P@MoOx/NF, the catalyst has good hydrogen evolution and oxygen evolution catalytic performance;

The second technical problem to be solved by the present invention is to provide a preparation method of the above catalyst IPBAP/Ni ₂ P@MoOx/NF.

In order to solve the above-mentioned technical problems, the preparation method of a high-efficiency total water splitting electrocatalyst IPBAP/Ni ₂ P@MoOx/NF according to the present invention comprises the following steps:

(1) select the porous nickel carrier to carry out pretreatment, standby;

(2) take by weighing ammonium molybdate, nickel nitrate and acetamide, add water and mix to obtain a loading solution;

(3) placing the porous nickel carrier in the loading solution, so that the porous nickel carrier is completely immersed in the loading solution, obtaining a nanoflower-shaped precursor compounded on the porous nickel carrier through a hydrothermal reaction, washing and drying, spare;

(4) The dried precursor is completely immersed in a potassium ferricyanide solution to react, and the reaction product is washed and dried, and then subjected to low-temperature phosphating treatment to obtain the obtained product.

Specifically, in the step (1), the porous nickel carrier includes foamed nickel.

Specifically, in the step (1), the pretreatment step includes the steps of placing the porous nickel carrier in a dilute hydrochloric acid solution, anhydrous ethanol and deionized water for ultrasonic treatment in sequence, and vacuum drying at a low temperature. step.

The concentration of the dilute hydrochloric acid solution used is preferably 3M, and the ultrasonic time in different solutions is preferably controlled to be 15min.

Specifically, in the step (2):

In the control of the ammonium molybdate and nickel nitrate, the molar ratio of molybdenum and nickel is 9:1-8:7;

The molar ratio of the acetamide to ammonium molybdate is controlled to be 10-30:1.

As for the amount of water in the load solution, for the purpose of dissolving ammonium molybdate, nickel nitrate and acetamide, the amount of water is suitable to be sufficient to dissolve the above substances, and it is suitable to completely impregnate the carrier.

Specifically, in the step (3), the temperature of the hydrothermal reaction is controlled to be 150-240° C., and the reaction time is 16-32 h.

Specifically, in the step (4), the concentration of the potassium ferricyanide solution is controlled to be 0.01M-0.04M, the soaking time is controlled to be 1-32h, and the volume dosage of the potassium ferricyanide solution is completely immersed as should.

Specifically, in the step (4), the low-temperature phosphating treatment step is performed in a tube furnace, which specifically includes placing a porcelain boat containing sodium hypophosphite on the air inlet end of the tube furnace, and at the same time at a distance The step of placing the porcelain boat containing the porous nickel material at 2 cm.

Specifically, in the step (4), the firing temperature of the low-temperature phosphating treatment step is controlled to be 300-400° C., and the holding time is 1-6 h.

Specifically, in the step (3) and/or (4), the washing step is washing with deionized water, and the drying step is drying at 40-60° C. for 10-15 hours.

The invention also discloses a high-efficiency total water splitting electrocatalyst IPBAP/Ni ₂ P@MoOx/NF prepared by the method, and the catalyst is an in-situ Prussian blue analog phosphide, nickel phosphide, molybdenum oxide and porous nickel. composite material.

The high-efficiency total water splitting electrocatalyst IPBAP/Ni ₂ P@MoOx/NF described in the present invention is to synthesize nano flower ball-shaped precursor by hydrothermal reaction with a certain proportion of ammonium molybdate and nickel nitrate; The composite material of in-situ Prussian blue analog phosphide, nickel phosphide, molybdenum oxide and nickel foam obtained by low-temperature phosphating after solution impregnation and loading. The catalyst utilizes the reaction of nickel ions and potassium ferricyanide to make Prussian blue analogs grow in situ on the molybdenum-nickel-based precursor nano-curds, and at the same time leaves a large number of nickel cation vacancies in the material, which improves the intrinsic properties of the material. While active, the active site of the material is further increased; through low temperature phosphating, the in situ generated Prussian blue analog and the nickel-based material in the precursor are phosphated to generate in situ Prussian blue analog phosphide and nickel phosphide , combining the excellent hydrogen evolution performance of molybdenum oxide and the excellent oxygen evolution performance of Prussian blue analog phosphide, while maintaining the excellent hydrogen evolution performance, the oxygen evolution performance has been greatly improved, and the electrolytic battery with efficient total water splitting performance is obtained. catalyst. At the same time, the preparation method of the whole catalyst is simple and feasible, and is suitable for industrial promotion.

Description of drawings

In order to make the content of the present invention easier to understand clearly, the present invention will be described in further detail below according to the specific embodiment 1 of the present invention and in conjunction with the accompanying drawings, wherein,

Fig. 1 is the SEM topography of the precursor obtained after soaking in potassium ferricyanide solution in Example 1;

Fig. 2 is the SEM topography of IPBAP/Ni ₂ P@MoOx/NF obtained in Example 1;

Fig. 3 is the XRD pattern of IPBAP/Ni ₂ P@MoOx/NF obtained in Example 1;

Fig. 4 is the LSV of IPBAP/Ni ₂ P@MoOx/NF material obtained in Example 1, the Tafel slope diagram and the relationship diagram of current density and time;

FIG. 5 is a comparison diagram of the hydrogen evolution performance and oxygen evolution performance of the IPBAP/Ni ₂ P@MoOx/NF material prepared in Example 1 and other materials.

Detailed ways

Example 1

The preparation method of the electrocatalyst IPBAP/Ni ₂ P@MoOx/NF for the total water splitting described in this embodiment includes the following steps:

(1) The commercial nickel foam was cut into a size of 10mm*20mm, followed by ultrasonic treatment in 3M dilute hydrochloric acid, absolute ethanol, and deionized water for 15min, and then vacuum-dried at 60°C for 12h, for later use;

(2) take by weighing the ammonium molybdate tetrahydrate of 0.1mmol, the hexahydrate nickel nitrate of 0.26mmol and the acetamide of 2mmol in addition, add 60ml deionized water and stir 2h, obtain load solution;

(3) Transfer the obtained load solution into the reaction kettle, add the previously treated foamed nickel, seal it and put it into an oven at 180 ° C for 24 hours; when the reaction kettle is cooled to room temperature, take out the foamed nickel, use deionized water Rinse 3 times, put it in a 60°C oven to dry for 12h;

(4) Soak the dried nickel foam in 0.01M potassium ferricyanide for 24h, take it out, rinse it with deionized water 3 times, put it in a 60°C oven to dry for 12h to obtain the desired precursor, and its SEM morphology The figure is shown in Figure 1;

Weigh 2g of sodium hypophosphite into the porcelain boat, put the porcelain boat into the air inlet of the tube furnace, and put the dried nickel foam into another porcelain boat at a distance of 2cm from the previous one. , phosphating at 400 °C at low temperature and holding for 2 h, and finally IPBAP/Ni ₂ P@MoOx/NF highly efficient electrocatalytic material for total water splitting was obtained.

As shown in Fig. 1, it can be seen from (1) in Fig. 1 that the structure of the nanosheets is evenly and tightly attached to the nickel foam, so it can provide many active sites for the material; from Fig. 1 It can be seen from (2) that the diameter of the nanosheet ball can be roughly estimated to be about 10 microns; it can be seen from (3) in Figure 1 that the nanosheets of this nanosheet ball are cross-vertically distributed to form a kind of Spherical, with extremely high surface area and stable structure; as can be seen from (4) in Figure 1, and as can be seen from Figure 1-4, after soaking potassium ferricyanide, the surface of the material is more Evenly distributed protrusions of similar size are Prussian blue analogs formed by the reaction of nickel ions with potassium ferricyanide.

As shown in Figure 2, it can be seen from (1) in Figure 2 that the material still maintains the structure of nanosheets after phosphating, which shows that low temperature phosphating will not change the microstructure of the material; from Figure 2 ( 2) It can be seen which protrusions before phosphating disappear, because these Prussian blue analogs shrink in volume after phosphating.

As shown in FIG. 3 , it can be seen that Fe ₂ P, Ni ₂ P, Mo ₄ O ₁₁ and Mo ₈ O ₂₃ are among the materials. Among them, Fe ₂ P comes from the phosphating product of Prussian blue analogs, Ni ₂ P comes from the phosphating products of Prussian blue analogs and NiO in the nanospheres after phosphating, Mo ₄ O ₁₁ and Mo ₈ O ₂₃ are mainly the constituents of nanospheres.

The LSV of the IPBAP/Ni ₂ P@MoOx/NF material obtained in this example, the Tafel slope diagram and the relationship diagram of the current density and time are shown in Figure 4; wherein,

(1) in Figure 4 is the LSV diagram of the hydrogen evolution of the material. It can be seen from the figure that the hydrogen evolution performance of the material is 61mV at 10mA/cm;

(2) in Figure 4 is the Tafel slope diagram converted from the LSV diagram of the material hydrogen evolution, it can be seen from the figure that the Tafel slope of the material hydrogen evolution is 67 mA/dec;

(3) in Figure 4 is the LSV diagram of the oxygen evolution of the material, from which it can be seen that the oxygen evolution performance of the material is 267mV at 100mA/ ^cm2 ;

(4) in Figure 4 is the Tafel slope diagram transformed from the material oxygen evolution LSV diagram, it can be seen from the figure that the Tafel slope of the material oxygen evolution is 27/mA/dec;

(5) in Figure 4 is the hydrogen evolution cycle of the material. It can be seen from the figure that the material can be maintained for 80h at 50 mA/cm ² without significant changes in the current density, so it has a good hydrogen evolution cycle performance;

(6) in Figure 4 is the oxygen evolution cycle of the material. It can be seen from the figure that the material can be maintained for 80h at 100mA/cm ² without significant changes in current density, so it has good oxygen evolution cycle performance.

Example 2

The preparation method of the electrocatalyst IPBAP/Ni ₂ P@MoOx/NF for the total water splitting described in this embodiment includes the following steps:

(1) The commercial nickel foam was cut into a size of 10mm*20mm, followed by ultrasonic treatment in 3M dilute hydrochloric acid, absolute ethanol, and deionized water for 15min, and then vacuum-dried at 60°C for 12h, for later use;

(2) take by weighing 0.1mmol of ammonium molybdate tetrahydrate, 0.35mmol of nickel nitrate hexahydrate and 2mmol of acetamide, add 60ml of deionized water and stir for 2h, to obtain a loaded solution;

(3) Transfer the obtained load solution into the reaction kettle, add the previously treated foamed nickel to seal and put it into an oven at 180 ° C for 24 hours of reaction; when the reaction kettle is cooled to room temperature, take out the foamed nickel and rinse with deionized water 3 times, put it into a 60°C oven to dry for 12h;

(4) Soak the dried nickel foam in 0.03M potassium ferricyanide for 24h, take it out, rinse it with deionized water 3 times, put it in a 60℃ oven to dry for 12h; weigh 4g of sodium hypophosphite and put it in the porcelain In the boat, put the porcelain boat into the air inlet of the tube furnace, and put the dried nickel foam into another porcelain boat at a distance of 2cm from the previous one, and phosphate it at a low temperature at 400 ° C and keep it warm. After 2 h, IPBAP/Ni ₂ P@MoOx/NF highly efficient electrocatalytic material for water splitting was finally obtained.

After measurement, when the current density of the electrocatalytic material obtained in this example is 10mA/cm , the hydrogen evolution overpotential is 93mV, and the Tafel slope is 112mV/dec ^{; when the current density is 100mA/cm 2 ,} the oxygen evolution overpotential is 353mV, the Tafel slope is 42mV/dec; at the same time, under constant voltage, the current density remains stable after 80h.

Example 3

The preparation method of the electrocatalyst IPBAP/Ni ₂ P@MoOx/NF for the total water splitting described in this embodiment includes the following steps:

(1) The commercial nickel foam was cut into a size of 10mm*20mm, followed by ultrasonic treatment in 3M dilute hydrochloric acid, absolute ethanol, and deionized water for 15min, and then vacuum-dried at 60°C for 12h, for later use;

(2) take by weighing 0.1mmol of ammonium molybdate tetrahydrate, 0.175mmol of nickel nitrate hexahydrate and 2mmol of acetamide, add 60ml of deionized water and stir for 2h to obtain a loaded solution;

(3) Transfer the obtained load solution into the reaction kettle, add the previously treated foamed nickel to seal and put it into an oven at 180 ° C for 24 hours of reaction; when the reaction kettle is cooled to room temperature, take out the foamed nickel and rinse with deionized water 3 times, put it into a 60°C oven to dry for 12h;

(4) Soak the dried nickel foam in 0.02M potassium ferricyanide for 24h, take it out and rinse it with deionized water 3 times, put it in a 60°C oven to dry for 12h; weigh 2g of sodium hypophosphite into the porcelain In the boat, put the porcelain boat into the air inlet of the tube furnace, and put the dried nickel foam into another porcelain boat at a distance of 2cm from the previous one, and phosphate it at a low temperature at 400 ° C and keep it warm. After 2 h, IPBAP/Ni ₂ P@MoOx/NF highly efficient electrocatalytic material for water splitting was finally obtained.

After measurement, when the current density of the electrocatalytic material obtained in this example is 10mA/cm , the hydrogen evolution overpotential is 69mV, and the Tafel slope is 72mV/dec ^{; when the current density is 100mA/cm 2 ,} the oxygen evolution overpotential is 383mV, the Tafel slope is 52mV/dec; meanwhile, under constant voltage, the current density remains stable after 80h.

Example 4

The preparation method of the electrocatalyst IPBAP/Ni ₂ P@MoOx/NF for the total water splitting described in this embodiment includes the following steps:

(1) The commercial nickel foam was cut into a size of 10mm*20mm, followed by ultrasonic treatment in 3M dilute hydrochloric acid, absolute ethanol, and deionized water for 15min, and then vacuum-dried at 60°C for 12h, for later use;

(2) take by weighing 0.1mmol of ammonium molybdate tetrahydrate, 0.26mmol of nickel nitrate hexahydrate and 1.5mmol of acetamide, add 60ml of deionized water and stir for 2h to obtain a loaded solution;

(3) Transfer the obtained load solution into the reaction kettle, add the previously treated foamed nickel, seal it and put it into an oven at 180 ° C for 24 hours; when the reaction kettle is cooled to room temperature, take out the foamed nickel, use deionized water Rinse 3 times, put it in a 60°C oven to dry for 12h;

(4) Soak the dried nickel foam in 0.02M potassium ferricyanide for 16h, rinse it with deionized water 3 times after taking it out, put it in a 60°C oven to dry for 12h; weigh 2g of sodium hypophosphite into the porcelain In the boat, put the porcelain boat into the air inlet of the tube furnace, and put the dried nickel foam into another porcelain boat at a distance of 2cm from the previous one, and phosphate it at a low temperature at 400 ° C and keep it warm. After 2 h, IPBAP/Ni ₂ P@MoOx/NF highly efficient electrocatalytic material for water splitting was finally obtained.

After measurement, the electrocatalytic material obtained in this example has a hydrogen evolution overpotential of 89mV and a Tafel slope of 103mV/dec when the current density is 10mA/cm ^{2 ;} when the current density is 100mA/cm ² , the oxygen evolution overpotential is 0.351mV, the Tafel slope is 45mV/dec; meanwhile, under constant voltage, the current density remains stable after 80h.

Example 5

The preparation method of the total water splitting electrocatalyst IPBAP/Ni ₂ P@MoO _X /NF described in this embodiment includes the following steps:

(1) The commercial nickel foam was cut into a size of 10mm*20mm, followed by ultrasonic treatment in 3M dilute hydrochloric acid, absolute ethanol, and deionized water for 15min, and then vacuum-dried at 60°C for 12h, for later use;

(2) take by weighing 0.1mmol of ammonium molybdate tetrahydrate, 0.26mmol of nickel nitrate hexahydrate and 1.8mmol of acetamide, add 60ml of deionized water and stir for 2h to obtain a loaded solution;

(3) Transfer the obtained load solution into the reaction kettle, add the previously treated foamed nickel, seal it and put it into an oven at 180 ° C for 24 hours; when the reaction kettle is cooled to room temperature, take out the foamed nickel, use deionized water Rinse 3 times, put it in a 60°C oven to dry for 12h;

(4) Soak the dried nickel foam in 0.01M potassium ferricyanide for 32h, rinse with deionized water 3 times after taking it out, put it in a 60°C oven to dry for 12h; weigh 2g of sodium hypophosphite into the porcelain In the boat, put the porcelain boat into the air inlet of the tube furnace, and put the dried nickel foam into another porcelain boat at a distance of 2cm from the previous one, and phosphate it at a low temperature at 400 ° C and keep it warm. After 2 h, IPBAP/Ni ₂ P@MoOx/NF highly efficient electrocatalytic material for water splitting was finally obtained.

After measurement, when the current density of the electrocatalytic material obtained in this example is 10mA/cm , the hydrogen evolution overpotential is 66mV, and the Tafel slope is 97mV/dec ^{; when the current density is 100mA/cm 2 ,} the oxygen evolution overpotential is 353mV, the Tafel slope is 49mV/dec; meanwhile, under constant voltage, the current density remains stable after 80h.

Comparative Example 1

The material of this comparative example is ex-situ growth of Prussian blue analogs (referred to as PBAP/MoOx/NF), and the specific preparation process is as follows:

(1) The commercial nickel foam was cut into a size of 10mm*20mm, followed by ultrasonic treatment in 3M dilute hydrochloric acid, absolute ethanol, and deionized water for 15min, and then vacuum-dried at 60°C for 12h, for later use;

(2) Weigh 0.1mmol of ammonium molybdate tetrahydrate and 2.0mmol of acetamide, add 60ml of deionized water and stir for 2h to obtain a loaded solution;

(3) Transfer the obtained load solution into the reaction kettle, add the previously treated foamed nickel, seal it and put it into an oven at 180 ° C for 24 hours; when the reaction kettle is cooled to room temperature, take out the foamed nickel, use deionized water Rinse 3 times, put it in a 60°C oven to dry for 12h;

(4) take by weighing the sodium citrate of 9.0mmol and the nickel nitrate hexahydrate of 6.0mmol and be dissolved in 200ml deionized water to form solution A; In addition, take by weighing the potassium ferricyanide of 4.0mmol and be dissolved in 200ml deionized water to form solution B;

(5) Mix solution A and B into solution C and stir for 15 minutes, then soak the dried nickel foam after the above hydrothermal reaction in solution C and water bath at 40°C for 1 hour, then keep at room temperature for 10 hours, take out Then put it in an oven at 60°C for 12h;

(6) Weigh 2g of sodium hypophosphite and put it into the porcelain boat, put the porcelain boat into the air inlet of the tube furnace, and put the dried foam nickel into another porcelain boat and the previous porcelain boat at the same time. The boats were separated by 2 cm, phosphated at a low temperature at 400 °C and kept for 2 h, and finally the electrocatalytic material of the PBAP/MoOx/NF comparison scheme was obtained.

Comparative Example 2

The material of this comparative example is the material that is not soaked in potassium ferricyanide (denoted as P-S-0), and the specific preparation process is:

(1) The commercial nickel foam was cut into a size of 10mm*20mm, followed by ultrasonic treatment in 3M dilute hydrochloric acid, absolute ethanol, and deionized water for 15min, and then vacuum-dried at 60°C for 12h, for later use;

(2) also take by weighing 0.1mmol of ammonium molybdate tetrahydrate, 0.26mmol of hexahydrate nickel nitrate and 2.0mmol of acetamide, add 60ml of deionized water and stir for 2h to obtain a loaded solution;

(3) Transfer the obtained load solution into the reaction kettle, add the previously treated foamed nickel, seal it and put it into an oven at 180 ° C for 24 hours; when the reaction kettle is cooled to room temperature, take out the foamed nickel, use deionized water Rinse 3 times, put it in a 60°C oven to dry for 12h;

(4) Weigh 2g of sodium hypophosphite and put it into the porcelain boat, put the porcelain boat into the air inlet of the tube furnace, and put the dried foam nickel into another porcelain boat and the previous porcelain boat at the same time. The boats were separated by 2 cm, phosphatized at a low temperature of 400 °C and kept for 2 h, and finally the electrocatalytic material of the P-S-0 comparison scheme was obtained.

Comparative Example 3

The material of this comparative example is a material without nickel doping and soaking (referred to as MoOx/NF). The specific preparation process is as follows:

(1) The commercial nickel foam was cut into a size of 10mm*20mm, followed by ultrasonic treatment in 3M dilute hydrochloric acid, absolute ethanol, and deionized water for 15min, and then vacuum-dried at 60°C for 12h, for later use;

(2) Weigh 0.1mmol of ammonium molybdate tetrahydrate and 2.0mmol of acetamide, add 60ml of deionized water and stir for 2h to obtain a loaded solution;

(3) Transfer the obtained load solution into the reaction kettle, add the previously treated foamed nickel, seal it and put it into an oven at 180 ° C for 24 hours; when the reaction kettle is cooled to room temperature, take out the foamed nickel, use deionized water Rinse 3 times, put it in a 60°C oven to dry for 12h;

(4) Weigh 2g of sodium hypophosphite and put it into the porcelain boat, put the porcelain boat into the air inlet of the tube furnace, and put the dried foam nickel into another porcelain boat and the previous porcelain boat at the same time. The boats were separated by 2 cm, phosphated at a low temperature of 400 °C and kept for 2 h, and finally the electrocatalytic material of the MoOx/NF comparison scheme was obtained.

The catalytic material prepared in Example 1 (referred to as PS-24), the ex-situ growth Prussian blue analog prepared in Comparative Example 1 (referred to as PBAP/MoOx/NF), and the non-immersed ferricyanide prepared in Comparative Example 2 were used respectively. Potassium-based material (PS-0), non-nickel-doped and soaked material (MoOx/NF) prepared in Comparative Example 3, and pure nickel foam (denoted as NF), commercial platinum carbon (denoted as Pt/C)/commercial Ruthenium oxide (referred to as RuO ₂ ) was compared for performance differences, and the results are shown in FIG. 5 . (1) in Figure 5 is the comparison between the hydrogen evolution performance of each material. It can be seen from the figure that pure nickel foam (NF) has the worst performance, because nickel foam is the base material, its hydrogen evolution performance can be Ignore; non-in situ grown Prussian blue analogs (PBAP/MoOx/NF), no immersion potassium ferricyanide (PS-0), no nickel doping and immersion (MoOx/NF), and commercial platinum carbon (Pt/ C) 177 mV, 91 mV, 90 mV and 27 mV at 10 mA/cm ² , respectively.

(2) in Figure 5 is the Tafel slope corresponding to the data in (1) in Figure 5. It can be seen from the figure that the ex-situ growth of Prussian blue analogs (PBAP/MoOx/NF), without soaking potassium ferricyanide (P-S -0), without Ni doping and soaking (MoOx/NF), and commercial platinum carbon (Pt/C), the Tafel slopes are 171 mV/dec, 105 mV/dec, 98 mV/dec, and 54 mV/dec, respectively.

(3) in Figure 5 is the comparison between the oxygen evolution performance of each material. It can be seen from the figure that pure nickel foam (NF) has the worst performance, because nickel foam is the matrix material, and its oxygen evolution Performance is negligible; ex-situ grown Prussian blue analogs (PBAP/MoOx/NF), no immersion potassium ferricyanide (PS-0), no nickel doping and immersion (MoOx/NF), and commercial ruthenium oxide (RuO ₂ ) 383mV, 371mV, 442mV and 457mV respectively at 100mA/cm ² .

(4) in Figure 5 is the Tafel slope corresponding to the data in (3) in Figure 5. It can be seen from the figure that the ex-situ growth of Prussian blue analogs (PBAP/MoOx/NF), without soaking potassium ferricyanide (PS -0), without nickel doping and soaking (MoOx/NF), and commercial ruthenium oxide (RuO ₂ ), the Tafel slopes were 52 mV/dec, 54 mV/dec, 81 mV/dec, and 85 mV/dec, respectively.

It can be seen that the catalyst material of the present invention has excellent hydrogen evolution performance and oxygen evolution performance, and has the electrocatalytic performance of high-efficiency total water splitting performance.

Obviously, the above-mentioned embodiments are only examples for clear description, and are not intended to limit the implementation manner. For those of ordinary skill in the art, changes or modifications in other different forms can also be made on the basis of the above description. There is no need and cannot be exhaustive of all implementations here. And the obvious changes or changes derived from this are still within the protection scope of the present invention.

Claims (10)

1. a preparation method of high-efficiency total water splitting electrocatalyst IPBAP/Ni ₂ P@MoOx/NF, is characterized in that, comprises the steps: (1) select the porous nickel carrier to carry out pretreatment, standby; (2) take by weighing ammonium molybdate, nickel nitrate and acetamide, add water and mix to obtain a loading solution; (3) placing the porous nickel carrier in the loading solution, so that the porous nickel carrier is completely immersed in the loading solution, obtaining a nanoflower-shaped precursor compounded on the porous nickel carrier through a hydrothermal reaction, washing and drying, spare; (4) The dried precursor is completely immersed in a potassium ferricyanide solution to react, and the reaction product is washed and dried, and then subjected to low-temperature phosphating treatment to obtain the obtained product. 2 . The method for preparing a high-efficiency total water splitting electrocatalyst IPBAP/Ni ₂ P@MoOx/NF according to claim 1 , wherein, in the step (1), the porous nickel carrier comprises nickel foam. 3 . 3. The preparation method of high-efficiency total water splitting electrocatalyst IPBAP/Ni ₂ P@MoOx/NF according to claim 1 or 2, characterized in that, in the step (1), the pretreatment step comprises The porous nickel carrier is sequentially placed in a dilute hydrochloric acid solution, anhydrous ethanol and deionized water for ultrasonic treatment, and vacuum drying at a low temperature. 4. the preparation method of the high-efficiency total water splitting electrocatalyst IPBAP/Ni ₂ P@MoOx/NF according to any one of claims 1-3, is characterized in that, in described step (2): In the control of the ammonium molybdate and nickel nitrate, the molar ratio of molybdenum and nickel is 9:1-8:7; The molar ratio of the acetamide to ammonium molybdate is controlled to be 10-30:1. 5. The preparation method of the high-efficiency total water splitting electrocatalyst IPBAP/Ni ₂ P@MoOx/NF according to any one of claims 1-4, wherein in the step (3), the hydrothermal reaction is controlled The temperature is 150-240 ℃, and the reaction time is 16-32h. 6. the preparation method of the high-efficiency total water splitting electrocatalyst IPBAP/Ni ₂ P@MoOx/NF according to any one of claims 1-5, is characterized in that, in described step (4), control described ferricyanide The concentration of potassium solution is 0.01M-0.04M, and the soaking time is controlled to be 1-32h. 7. The preparation method of the high-efficiency total water splitting electrocatalyst IPBAP/Ni ₂ P@MoOx/NF according to any one of claims 1-6, characterized in that, in the step (4), the low-temperature phosphating treatment The step is performed in a tube furnace, and specifically includes the steps of placing a porcelain boat containing sodium hypophosphite at the inlet end of the tube furnace, and placing a porcelain boat containing the porous nickel material at a distance of 2 cm. 8. The preparation method of high-efficiency total water splitting electrocatalyst IPBAP/Ni ₂ P@MoOx/NF according to claim 7, characterized in that, in the step (4), the firing of the low-temperature phosphating treatment step is controlled The temperature is 300-400°C, and the holding time is 1-6h. 9. The preparation method of the high-efficiency total water splitting electrocatalyst IPBAP/Ni ₂ P@MoOx/NF according to any one of claims 1-8, characterized in that, in the step (3) and/or (4), The washing step is washing with deionized water, and the drying step is drying at 40-60° C. for 10-15 hours. 10. The high-efficiency total water splitting electrocatalyst IPBAP/Ni ₂ P@MoOx/NF prepared by the method of any one of claims 1-9, wherein the catalyst is an in-situ Prussian blue analog phosphide, phosphorus A composite of nickel oxide, molybdenum oxide and porous nickel.

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