阅读说明：本技术 水热法制备的金属氢氧化物水热c-复合oer材料 (Metal hydroxide hydrothermal C-composite OER material prepared by hydrothermal method ) 是由 陈彦霖 凌宇鑫 于 2021-09-05 设计创作，主要内容包括：本发明提供水热法制备的金属氢氧化物水热C-复合OER材料,涉及电化学催化剂技术领域。该金属氢氧化物水热C-复合OER材料的制备方法,包括以下步骤：S1.配置溶液、S2.水热反应、S3.产物处理和S4.最终制备。通过选用金属氢氧化物与水热碳相结合,金属过渡氢氧化物是一种优异的OER电化学活性催化剂,因为它们具有低成本,高效率,良好的催化性能和高稳定性,可以充分发挥水热碳的表面吸附作用,通过水热方法处理的葡萄糖来制备生成的水热碳晶型未被破坏,碳材料也已经部分石墨化,最终的OER性能也表现良好,稳定性可以保持8个小时以上,最终制备出来的粉体材料产率也很高,更加有利于后面的大规模商业化生产,值得大力推广。(The invention provides a hydrothermal C-composite OER material of metal hydroxide prepared by a hydrothermal method, and relates to the technical field of electrochemical catalysts. The preparation method of the metal hydroxide hydrothermal C-composite OER material comprises the following steps: s1, preparing a solution, S2, carrying out hydrothermal reaction, S3, treating a product and S4, and finally preparing. By selecting metal hydroxide to combine with hydrothermal carbon, the metal transition hydroxide is an excellent OER electrochemical active catalyst, because the metal hydroxide and the hydrothermal carbon have low cost, high efficiency, good catalytic performance and high stability, the surface adsorption effect of the hydrothermal carbon can be fully exerted, the hydrothermal carbon crystal form prepared by glucose treated by a hydrothermal method is not damaged, the carbon material is partially graphitized, the final OER performance is good, the stability can be kept for more than 8 hours, the yield of the finally prepared powder material is high, the powder material is more beneficial to the subsequent large-scale commercial production, and the method is worthy of great popularization.)

1. The metal hydroxide hydrothermal C-composite OER material prepared by the hydrothermal method is characterized in that: the preparation method of the metal hydroxide hydrothermal C-composite OER material comprises the following steps:

s1, preparing a solution

Taking 24-44 ml of 10mmol glucose and 6-11 ml of 2.5mmol anhydrous phloroglucinol, putting the glucose and the anhydrous phloroglucinol into a beaker, then slowly adding metal salt and acetic acid into the beaker in sequence, stirring the inside of the beaker at the rotating speed of 50-100 r/min for 25-30 min, and preparing an aqueous solution;

s2, hydrothermal reaction

Taking out the prepared aqueous solution, putting the aqueous solution into a hydrothermal kettle, stirring the aqueous solution in the hydrothermal kettle at a rotating speed of 200-400 r/min for 30-35 min, and carrying out hydrothermal treatment in the hydrothermal kettle at a temperature of 190-200 ℃ for 12-15 h;

s3, product treatment

Standing the hydrothermal kettle for 6-8 h after hydrothermal reaction, taking out sediment at the bottom of the hydrothermal kettle, putting the sediment into a vacuum pump filter for pump filtration, putting the sediment into a filter for washing by using distilled water after the pump filtration is finished, putting the sediment into a dryer for drying after washing, and drying to obtain hydrothermal carbon powder;

s4, final preparation

Taking 60mg of hydrothermal carbon powder, weighing acetylene black and PVDF according to the mass ratio of active substances, namely acetylene black to PVDF, of 8:1:1, transferring the acetylene black and PVDF into an agate mortar, grinding for 10-15 min, adding 1-2 mL of 1-methyl-2-pyrrolidone, further grinding for more than 20min, taking out the ground powder by using a plastic dropper after grinding is finished, uniformly coating the ground powder on a processed foamed nickel sheet, controlling the coating area to be 0.9cm 2-1.1 cm2, drying the coated foamed nickel sheet in an oven at 80-85 ℃ for more than 8h, then putting the foamed nickel sheet into a tabletting machine, and tabletting under the environment of 10-15 MPa to obtain the composite electrode material.

2. The hydrothermal C-composite OER material of claim 1, wherein: the S1 step configures one or more of FeSO4 & 7H2O, CoSO4 & 7H2O and MnSO4 & H2O in the metal salt species in the solution.

3. The hydrothermal C-composite OER material of claim 1, wherein: and the volume ratio of the glucose to the anhydrous phloroglucinol in the solution prepared in the step S1 is 4: 1.

4. the hydrothermal C-composite OER material of claim 1, wherein: the step S1 is to prepare the ratio of glucose, anhydrous phloroglucinol, metal salt and acetic acid in the solution according to the molar ratio of 10:2.5:1: 350.

5. The hydrothermal C-composite OER material of claim 1, wherein: and the drying temperature in the dryer in the product treatment in the step S3 is 150-200 ℃.

Technical Field

The invention relates to the technical field of electrochemical catalysts, in particular to a metal hydroxide hydrothermal C-composite OER material prepared by a hydrothermal method.

Background

With the development of economy, the consumption of coal and petroleum is continuously increased, fossil fuel resources are gradually exhausted, and environmental pollution is increasingly serious, so that the development of a high-efficiency, clean and renewable new energy source is urgently needed by human society, the preparation of hydrogen by electrolyzing water is one of important directions of the future development of renewable energy sources, the preparation of hydrogen by electrolyzing water is the most common method for preparing hydrogen, two half reactions exist in the hydrogen production by electrolyzing water, reactions involving four electrons exist in the anode process under different acid-base conditions, the kinetic inertia exists, the overpotential is high, and the disadvantages greatly limit the efficiency of the water electrolysis reaction.

Many metal catalysts are in a thermodynamically unstable state: the metal itself is oxidized before the oxygen evolution reaction occurs, the surface of the electrode is dissolved, or both the precipitation of the oxide and the corrosion of the metal occur, resulting in poor catalyst stability.

Disclosure of Invention

Technical problem to be solved

Aiming at the defects of the prior art, the invention provides a metal hydroxide hydrothermal C-composite OER material prepared by a hydrothermal method, and solves the problem of poor stability of the existing metal catalyst.

(II) technical scheme

In order to achieve the purpose, the invention is realized by the following technical scheme: the metal hydroxide hydrothermal C-composite OER material prepared by a hydrothermal method comprises the following steps:

s1, preparing a solution

Taking 24-44 ml of 10mmol glucose and 6-11 ml of 2.5mmol anhydrous phloroglucinol, putting into a beaker, then slowly adding metal salt and acetic acid into the beaker in sequence, stirring the beaker at the rotating speed of 50-100 r/min for 25-30 min, and preparing into an aqueous solution;

s2, hydrothermal reaction

Taking out the prepared aqueous solution, putting the aqueous solution into a hydrothermal kettle, stirring the aqueous solution in the hydrothermal kettle at a rotating speed of 200-400 r/min for 30-35 min, and carrying out hydrothermal treatment in the hydrothermal kettle at a temperature of 190-200 ℃ for 12-15 h;

s3, product treatment

Standing the hydrothermal kettle for 6-8 hours after hydrothermal reaction, taking out sediment at the bottom of the hydrothermal kettle, putting the sediment into a vacuum pump filter for pump filtration, putting the sediment into a filter for washing by using distilled water after the pump filtration is finished, putting the sediment into a dryer for drying after washing, and drying to obtain hydrothermal carbon composite powder;

s4, final preparation

Taking 60mg of hydrothermal carbon powder, weighing acetylene black and PVDF according to the mass ratio of active substances, namely acetylene black to PVDF, of 8:1:1, transferring the acetylene black and PVDF into an agate mortar, grinding for 10-15 min, adding 1-2 mL of 1-methyl-2-pyrrolidone, further grinding for more than 20min, taking out the ground powder by using a plastic dropper after grinding is finished, uniformly coating the ground powder on a processed foamed nickel sheet, controlling the coating area to be 0.9cm 2-1.1 cm2, drying the coated foamed nickel sheet in an oven at 80-85 ℃ for more than 8h, then putting the foamed nickel sheet into a tabletting machine, and tabletting under the environment of 10-15 MPa to obtain the composite electrode material.

Preferably, the S1 step configures one or more of FeSO 4.7H 2O, CoSO 4.7H 2O and MnSO 4.h 2O within the species of the metal salt in the solution.

Preferably, the volume ratio of the glucose to the anhydrous phloroglucinol in the solution prepared in the step S1 is 4: 1.

preferably, the step S1 is to prepare the solution with glucose, anhydrous phloroglucinol, metal salt and acetic acid in a molar ratio of 10:2.5:1: 350.

Preferably, the drying temperature in the dryer in the product treatment in the step S3 is 150-200 ℃.

(III) advantageous effects

The invention provides a metal hydroxide hydrothermal C-composite OER material prepared by a hydrothermal method. The method has the following beneficial effects:

the invention combines the metal hydroxide with the hydrothermal carbon, the metal transition hydroxide is an excellent OER electrochemical active catalyst, because the metal hydroxide and the hydrothermal carbon have low cost, high efficiency, good catalytic performance and high stability, the surface adsorption effect of the hydrothermal carbon can be fully exerted, the surface of the hydrothermal carbon without high-temperature treatment and activation contains a large amount of oxygen-containing functional groups and is convenient for further modification, atoms with stronger isoelectric negativity such as carbon and nitrogen can be doped, a net positive charge is generated on adjacent carbon atoms (C +), an n-n dissociation domain is formed, the thermal activity barrier of OOH is optimized, the adsorption and charge transfer of oxygen are promoted, the OER activity is enhanced, the yield of hydrothermal carbon microspheres is improved by adding phloroglucinol, more oxygen-containing functional groups are formed on the surface of a final product in a period, and the adsorption of oxygen atoms in the OER process is promoted, meanwhile, acetic acid is added to increase the specific surface area of the finally synthesized hydrothermal carbon material, as acetic acid is a decisive additive for constructing a high-porosity hierarchical porous structure, the yield of the finally prepared powder material is also high, which is more beneficial to the subsequent large-scale commercial production, glucose is finally converted into a hydrothermal carbon microsphere composite material through a series of complex reactions, most hydrothermal carbon microspheres are in an agglomerated state, the particle size of the final hydrothermal carbon microspheres is about 2 mu m, the hydrothermal carbon crystal form prepared by the glucose treated by a hydrothermal method is not damaged, the carbon material is partially graphitized, the final OER performance is good, the optimum overpotential is 321mV, the Tafel slope is 72.1mV dec-1, the charge transfer resistance is only 0.509 omega, and the stability can be kept for more than 8 hours, is worthy of being widely popularized.

Drawings

FIG. 1 is a scanning electron microscope image of a hydrothermal carbon composite of the present invention;

fig. 2 is an XRD chart of the hydrothermal carbon composite of the present invention.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

The first embodiment is as follows:

as shown in fig. 1-2, an embodiment of the present invention provides a metal hydroxide hydrothermal C-composite OER material prepared by a hydrothermal method, and a method for preparing the metal hydroxide hydrothermal C-composite OER material, including the following steps:

s1, preparing a solution

Respectively weighing 44mL, 40mL, 32mL and 24mL of 10mmol glucose and 11mL, 10mL, 8mL and 6mL of 2.5mmol anhydrous phloroglucinol, respectively placing the glucose and the anhydrous phloroglucinol into four different beakers, then slowly adding metal salt into the beakers, respectively adding 5mL, 10mL, 20mL and 30mL of acetic acid into the four beakers, and stirring the beakers at the rotating speed of 100r/min for 30min to prepare 60mL of aqueous solution;

s2, hydrothermal reaction

Taking out the prepared aqueous solution, respectively placing the aqueous solution into hydrothermal kettles, stirring the hydrothermal kettles at the rotating speed of 400r/min for 35min, and carrying out hydrothermal treatment on the hydrothermal kettles at the temperature of 200 ℃ for 12 h;

s3, product treatment

Standing the hydrothermal kettle for 8 hours after hydrothermal reaction, taking out sediment at the bottom of the hydrothermal kettle, putting the sediment into a vacuum pump filter for suction filtration, putting the sediment into a filter for washing by using distilled water after the suction filtration is finished, putting the sediment into a dryer for drying after washing, and drying to obtain hydrothermal carbon composite powder;

s4, final preparation

And finally, respectively naming the four finally prepared samples as C-HTC @ HAc5, C-HTC @ HAc10, C-HTC @ HAc20 and C-HTC @ HAc30, taking 60mg of hydrothermal carbon powder, weighing acetylene black and PVDF according to the mass ratio of active substances, namely acetylene black to PVDF, of 8:1:1, transferring the acetylene black and PVDF into an agate mortar, grinding for 10min, adding 2mL of 1-methyl-2-pyrrolidone, continuing grinding for more than 20min, taking out the ground powder by using a plastic dropper after grinding is finished, uniformly coating the ground powder on a treated foamed nickel sheet, controlling the coated area to be 1cm2, placing the coated foamed nickel sheet into an oven at 80 ℃ for drying for more than 8h, then placing the foamed nickel sheet into a tabletting machine, and pressing into tablets under the environment of 10MPa to obtain the composite electrode material.

The S1 step configures one or more of FeSO4 & 7H2O, CoSO4 & 7H2O and MnSO4 & H2O in the metal salt species in the solution.

S1, preparing a solution with the volume ratio of glucose to anhydrous phloroglucinol being 4: 1.

step S1, glucose, anhydrous phloroglucinol, metal salt and acetic acid in the solution are prepared according to the molar ratio of 10:2.5:1: 350.

The drying temperature in the dryer in the product treatment of the step S3 was 200 ℃.

Example two:

as shown in fig. 1-2, an embodiment of the present invention provides a metal hydroxide hydrothermal C-composite OER material prepared by a hydrothermal method, and a method for preparing the metal hydroxide hydrothermal C-composite OER material, including the following steps:

s1, preparing a solution

Respectively weighing 32mL of 10mmol glucose and 8mL of 2.5mmol anhydrous phloroglucinol, putting the glucose and the anhydrous phloroglucinol into four different beakers, then taking three of the beakers, respectively adding FeSO4 & 7H2O, CoSO4 & 7H2O and MnSO4 & H2O, controlling the molar weight to be 0.25mmol, respectively adding 20mL of acetic acid into the four beakers, stirring the beakers for 25-30 min at the rotating speed of 50-100 r/min, and preparing 60mL of aqueous solution;

s2, hydrothermal reaction

Taking out the prepared aqueous solution, putting the aqueous solution into a hydrothermal kettle, stirring the aqueous solution in the hydrothermal kettle at a rotating speed of 200r/min for 30min, and carrying out hydrothermal treatment on the aqueous solution in the hydrothermal kettle at a temperature of 200 ℃ for 12 h;

s3, product treatment

Standing the hydrothermal kettle for 6 hours after hydrothermal reaction is finished, taking out sediment at the bottom of the hydrothermal kettle, putting the sediment into a vacuum pump filter for suction filtration, putting the sediment into a filter for washing by using distilled water after the suction filtration is finished, putting the sediment into a dryer for drying after washing, and drying to obtain hydrothermal carbon composite powder;

s4, final preparation

The three groups of samples added with metal salt are named as C-HTC @ Fe, C-HTC @ Co and C-HTC @ Mn respectively, 60mg of hydrothermal carbon powder is weighed, acetylene black and PVDF are weighed according to the mass ratio of active substances to acetylene black to PVDF being 8:1:1, the mixture is transferred to an agate mortar and ground for 10min, 1mL of 1-methyl-2-pyrrolidone is added, the mixture is ground for more than 20min, a plastic dropper is used for coating a treated foam nickel sheet, the coating area is controlled to be about 1cm2, the coated foam nickel sheet is placed in an oven at 80 ℃ and dried for more than 8h, and then the dried foam nickel sheet is pressed into a sheet under 10MPa to obtain the composite electrode material.

The S1 step configures one or more of FeSO4 & 7H2O, CoSO4 & 7H2O and MnSO4 & H2O in the metal salt species in the solution.

S1, preparing a solution with the volume ratio of glucose to anhydrous phloroglucinol being 4: 1.

step S1, glucose, anhydrous phloroglucinol, metal salt and acetic acid in the solution are prepared according to the molar ratio of 10:2.5:1: 350.

The drying temperature in the dryer in the product treatment of the step S3 was 150 ℃.

Example three:

as shown in fig. 1-2, an embodiment of the present invention provides a metal hydroxide hydrothermal C-composite OER material prepared by a hydrothermal method, and a method for preparing the metal hydroxide hydrothermal C-composite OER material, including the following steps:

s1, preparing a solution

Respectively weighing 32mL of 10mmol glucose and 8mL of 2.5mmol anhydrous phloroglucinol, putting the glucose and the anhydrous phloroglucinol into four different beakers, respectively adding 0.25mmol, 0.5mmol, 0.75mmol and 1mmol FeSO 4.7H 2O into the four beakers, then adding 20mL acetic acid, stirring the beakers for 30min at the rotating speed of 100r/min, and preparing 60mL aqueous solution;

s2, hydrothermal reaction

Taking out the prepared aqueous solution, putting the aqueous solution into a hydrothermal kettle, stirring the aqueous solution in the hydrothermal kettle at a rotating speed of 200r/min for 30min, and carrying out hydrothermal treatment on the aqueous solution in the hydrothermal kettle at a temperature of 200 ℃ for 12 h;

s3, product treatment

Standing the hydrothermal kettle for 6-8 h after hydrothermal reaction, taking out sediment at the bottom of the hydrothermal kettle, putting the sediment into a vacuum pump filter for pump filtration, putting the sediment into a filter for washing by using distilled water after the pump filtration is finished, putting the sediment into a dryer for drying after washing, and drying to obtain hydrothermal carbon powder;

s4, final preparation

Taking 60-65 mg of hydrothermal carbon powder, weighing acetylene black and PVDF according to the mass ratio of active substances, namely acetylene black to PVDF, of 8:1:1, transferring the acetylene black and PVDF into an agate mortar, grinding for 10min, adding 1mL of 1-methyl-2-pyrrolidone, continuously grinding for more than 20min, taking out the ground powder by using a plastic dropper after grinding is finished, uniformly coating the ground powder on a processed foamed nickel sheet, controlling the coating area to be 1cm2, drying the coated foamed nickel sheet in an oven at 80 ℃ for more than 8h, putting the foamed nickel sheet into a tabletting machine, and tabletting under the environment of 10MPa to obtain the composite electrode material.

The S1 step configures one or more of FeSO4 & 7H2O, CoSO4 & 7H2O and MnSO4 & H2O in the metal salt species in the solution.

S1, preparing a solution with the volume ratio of glucose to anhydrous phloroglucinol being 4: 1.

step S1, glucose, anhydrous phloroglucinol, metal salt and acetic acid in the solution are prepared according to the molar ratio of 10:2.5:1: 350.

The drying temperature in the dryer in the product treatment of the step S3 was 150 ℃.

Compared with experimental data, the improvement of the OER catalytic performance is most obvious when the addition of the metal salt is increased to 5mmoL, the surface adsorption effect of hydrothermal carbon can be fully exerted by selecting and combining the metal hydroxide and the hydrothermal carbon, the surface of the hydrothermal carbon which is not subjected to high-temperature treatment and activation contains a large number of oxygen-containing functional groups and is convenient for further modification, atoms with stronger isoelectric negativity of carbon and nitrogen can be doped to generate a net positive charge on adjacent carbon atoms (C +), an n-n dissociation domain is formed, the thermal activity potential barrier of OOH is optimized, the adsorption and charge transfer of oxygen are promoted, the OER activity is enhanced, the yield of the hydrothermal carbon microsphere is increased by adding phloroglucinol, more oxygen-containing functional groups are formed on the surface of a final product in a period, the adsorption of oxygen atoms in the OER process is promoted, and simultaneously acetic acid is added to increase the specific surface area of the finally synthesized hydrothermal carbon material, because acetic acid is a decisive additive for constructing a high-porosity hierarchical porous structure, the finally prepared powder material has high yield and is more favorable for subsequent large-scale commercial production, glucose is finally converted into a hydrothermal carbon microsphere composite material through a series of complex reactions, most hydrothermal carbon microspheres are in an agglomerated state, the particle size of the final hydrothermal carbon microspheres is about 2 mu m, the hydrothermal carbon crystal form prepared from the glucose treated by a hydrothermal method is not damaged, the carbon material is also partially graphitized, the final OER performance is good, the optimum overpotential is 321mV, the Tafel slope is 72.1mV dec-1, the charge transfer resistance is only 0.509 omega, and the stability can be kept for more than 8 hours at the current density of 10mA · cm-2.

Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.