CN108435178B - Oxide with hexagonal structure, preparation method and application thereof in oxygen evolution reaction - Google Patents

Oxide with hexagonal structure, preparation method and application thereof in oxygen evolution reaction Download PDF

Info

Publication number
CN108435178B
CN108435178B CN201810326691.2A CN201810326691A CN108435178B CN 108435178 B CN108435178 B CN 108435178B CN 201810326691 A CN201810326691 A CN 201810326691A CN 108435178 B CN108435178 B CN 108435178B
Authority
CN
China
Prior art keywords
catalyst
oxygen evolution
oxide
edta
preparation
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Active
Application number
CN201810326691.2A
Other languages
Chinese (zh)
Other versions
CN108435178A (en
Inventor
周嵬
朱印龙
杨广明
邵宗平
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Nanjing Tech University
Original Assignee
Nanjing Tech University
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Nanjing Tech University filed Critical Nanjing Tech University
Priority to CN202010942624.0A priority Critical patent/CN112191242B/en
Priority to CN201810326691.2A priority patent/CN108435178B/en
Publication of CN108435178A publication Critical patent/CN108435178A/en
Application granted granted Critical
Publication of CN108435178B publication Critical patent/CN108435178B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • B01J35/33—
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
    • B01J23/002—Mixed oxides other than spinels, e.g. perovskite
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
    • B01J23/16—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of arsenic, antimony, bismuth, vanadium, niobium, tantalum, polonium, chromium, molybdenum, tungsten, manganese, technetium or rhenium
    • B01J23/32—Manganese, technetium or rhenium
    • B01J23/34—Manganese
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
    • B01J23/70—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper
    • B01J23/76—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper combined with metals, oxides or hydroxides provided for in groups B01J23/02 - B01J23/36
    • B01J23/78—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper combined with metals, oxides or hydroxides provided for in groups B01J23/02 - B01J23/36 with alkali- or alkaline earth metals
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
    • B01J23/70—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper
    • B01J23/76—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper combined with metals, oxides or hydroxides provided for in groups B01J23/02 - B01J23/36
    • B01J23/83—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper combined with metals, oxides or hydroxides provided for in groups B01J23/02 - B01J23/36 with rare earths or actinides
    • B01J35/50—
    • C—CHEMISTRY; METALLURGY
    • C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
    • C25B—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES FOR THE PRODUCTION OF COMPOUNDS OR NON-METALS; APPARATUS THEREFOR
    • C25B1/00—Electrolytic production of inorganic compounds or non-metals
    • C25B1/01—Products
    • C25B1/02—Hydrogen or oxygen
    • C25B1/04—Hydrogen or oxygen by electrolysis of water
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/86—Inert electrodes with catalytic activity, e.g. for fuel cells
    • H01M4/90—Selection of catalytic material
    • H01M4/9016—Oxides, hydroxides or oxygenated metallic salts
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J2523/00—Constitutive chemical elements of heterogeneous catalysts
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y02E60/30—Hydrogen technology
    • Y02E60/36—Hydrogen production from non-carbon containing sources, e.g. by water electrolysis
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y02E60/30—Hydrogen technology
    • Y02E60/50—Fuel cells

Abstract

The invention relates to an oxygen evolution reaction electrocatalyst of oxide with a hexagonal structure, and the structural general formula is A8B4O15Wherein, the A site cation is one or more of rare earth metal ions or alkaline earth metal ions, and the B site cation is one or more of transition metal ions. The oxygen evolution reaction electrocatalyst has excellent Oxygen Evolution (OER) catalytic performance and long-term stability in alkaline solution, and the activity and the stability of the oxygen evolution reaction electrocatalyst are superior to those of commercial noble metal oxide RuO2A catalyst. The preparation method of the catalyst is simple to operate, is easy for large-scale production, can be widely applied to electrolytic water, metal-air batteries and other energy storage and conversion technologies related to oxygen evolution reaction, and has high practical value.

Description

Oxide with hexagonal structure, preparation method and application thereof in oxygen evolution reaction
Technical Field
The invention belongs to the field of electrochemical catalysts, and particularly relates to an oxygen evolution reaction electrocatalyst of an oxide with a hexagonal crystal structure, which has high Oxygen Evolution (OER) activity and can be used for water electrolysis, metal-air batteries and other electrocatalysts related to energy storage and conversion technologies of oxygen evolution reaction.
Background
In the world today, energy problems are a key issue for the development of human society. With the transition use of fossil energy, environmental and pollution problems such as global warming, greenhouse effect, air pollution, etc. become increasingly severe. In order to realize the sustainable development of human beings, the development and utilization of new economic, efficient and clean energy are the subjects of the world energy technology in the 21 st century. At present, renewable energy sources such as solar energy, wind energy and tidal energy are in worldwide attention, however, the power generation of the new energy sources belongs to an uncontrollable power source and has the defects of intermittency, instability and the like. The development of advanced electrochemical energy storage and conversion technologies, such as fuel cells, metal-air batteries, electrolytic water, etc., is the fundamental approach to the problem. Among them, in the field of hydrogen production by electrochemical hydrolysis, the Oxygen Evolution Reaction (OER) at the anode is much more difficult than the hydrogen evolution reaction at the cathode. In order to improve the electrochemical efficiency of the electrolyzed water, the search for the anode oxygen evolution catalyst with excellent performance to reduce the overpotential of the anode oxygen evolution reaction as much as possible is a difficult point and a hot point problem in the research of the electrolyzed water. The noble metal Ru or Ir and the oxide thereof have high catalytic activity for oxygen evolution reaction. However, these noble metal catalysts have limited their large-scale use due to excessive cost, low inventory and stability problems.
Therefore, it is particularly necessary to develop a catalyst which can replace noble metal oxygen evolution and has high efficiency, stability, low cost and simple preparation. Among various non-noble metal catalysts, perovskite oxides have attracted extensive attention due to the advantages of low cost, abundant resources, strong adjustability of structure and components, environmental friendliness, and the like.
Disclosure of Invention
The invention aims to solve the problems of high price, resource shortage, poor stability and the like of the existing oxygen evolution catalyst and provides an oxygen evolution electrocatalyst with a new structure. The series of catalysts not only have excellent Oxygen Evolution (OER) catalytic performance and long-term stability, but also have the advantages of low cost, environmental friendliness, simple preparation method and the like.
In a first aspect of the present invention, there is provided:
an oxide with a hexagonal structure and a general structural formula of A8B4O15Wherein A is one or more of rare earth metal elements or alkaline earth metal elements, and B is one or more of transition metal elements.
In one embodiment, the element A is preferably one or more of Ba, Sr, La, Pr, Nd, Sm, Gd and Eu, and the element B is preferably one or more of Co, Fe, Mn and Ni.
In one embodiment, the above formula A is preferred8B4O15Is Ba4Sr4Co4O15、Ba4Sr4Co3.2Fe0.8O15、Ba4Sr4Mn4O15、Ba3.5Sr3.5LaCo4O15、Ba3Sr3La2Co4O15、Ba6La2Co4O15、Ba4Sr4Fe4O15、Ba6La2Fe4O15Or Ba6Pr2Fe4O15。
In a second aspect of the present invention, there is provided:
the preparation method of the oxide with the hexagonal crystal structure is prepared by a solid-phase reaction method, a sol-gel method, a coprecipitation method, a combustion method, a hydrothermal method or a microwave method and the like according to the stoichiometric ratio.
In one embodiment, the preparation is by a sol-gel process.
In one embodiment, the sol-gel process comprises the steps of: dissolving nitrates of the element A and the element B in water according to a stoichiometric ratio to obtain an aqueous solution; dissolving EDTA in ammonia water, adding the aqueous solution, adding citric acid and ammonia water to adjust the pH value to 6-8, wherein the pH value is adjusted according to the metal ions of the element A and the element B: EDTA: the molar ratio of citric acid is 1:1: 2; heating and stirring to form transparent sol, carrying out heat treatment on the sol, and roasting to obtain the catalyst.
In one embodiment, the heat treatment is performed at 200-300 ℃; the roasting temperature is 900-1100 ℃, and the roasting time is 2-20 h.
In a second aspect of the present invention, there is provided:
use of the above oxide having a hexagonal structure in an oxygen evolution reaction.
Advantageous effects
The oxygen evolution catalyst has excellent Oxygen Evolution (OER) activity and operation stability, and the activity and the stability are superior to those of commercial noble metal oxide RuO2The catalyst can be used as an electrocatalyst in the fields of renewable fuel cells, rechargeable metal-air batteries, water electrolysis and the like. The oxide with hexagonal structure can adopt the traditional solThe preparation method is simple and is suitable for large-scale preparation.
Drawings
Fig. 1 shows the structure of an oxide having a hexagonal structure according to the present invention.
FIG. 2 shows Ba in example 1 of the present invention4Sr4Co4O15X-ray diffraction (XRD) profile of the catalyst.
FIG. 3 is Ba in example 1 of the present invention4Sr4Co4O15Catalyst and commercial RuO2Catalyst in O2Comparison of polarization curves in saturated 0.1mol/L KOH solutions.
FIG. 4 shows Ba in example 1 of the present invention4Sr4Co4O15Catalyst and commercial RuO2Catalyst in O2Stability comparison graph in saturated 0.1mol/L KOH solution.
FIG. 5 shows Ba in example 2 of the present invention4Sr4Co3.2Fe0.8O15X-ray diffraction (XRD) profile of the catalyst.
FIG. 6 shows Ba in example 2 of the present invention4Sr4Co3.2Fe0.8O15Catalyst in O2Saturation of the polarization curve in a 0.1mol/L KOH solution.
FIG. 7 shows Ba in example 2 of the present invention4Sr4Co3.2Fe0.8O15Catalyst in O2Stability test chart in saturated 0.1mol/L KOH solution.
FIG. 8 shows Ba in example 3 of the present invention3.5Sr3.5LaCo4O15X-ray diffraction (XRD) profile of the catalyst.
FIG. 9 shows Ba in example 3 of the present invention3.5Sr3.5LaCo4O15Catalyst in O2Saturation of the polarization curve in a 0.1mol/L KOH solution.
FIG. 10 shows Ba in example 3 of the present invention3.5Sr3.5LaCo4O15Catalyst in O2Stability in saturated 0.1mol/L KOH solutionAnd (6) testing the graph.
FIG. 11 shows Ba in example 4 of the present invention4Sr4Fe4O15X-ray diffraction (XRD) profile of the catalyst.
FIG. 12 shows Ba in example 4 of the present invention4Sr4Fe4O15Catalyst in O2Polarization profile in saturated 0.1mol/L KOH solution.
FIG. 13 shows a conventional Ba0.5Sr0.5FeO3X-ray diffraction (XRD) profile of cubic perovskite structure.
FIG. 14 shows a conventional cubic Ba prepared in comparative example 10.5Sr0.5FeO3Catalyst and hexagonal Ba4Sr4Fe4O15Catalyst in O2Comparison of polarization curves in saturated 0.1mol/L KOH solutions.
Detailed Description
In the conventional perovskite oxide (the structural general formula is ABO)3) In (B) BO composed of an active transition metal B and lattice oxygen O6Hexahedrons are considered as active units for OER catalytic reactions. However, the hexagonal structure oxide of the present invention has not only BO structurally, as compared with the conventional perovskite oxide6Hexahedron and BO4Tetrahedron (see fig. 1). The OER active center of the oxide with a hexagonal structure is BO6Hexahedron and three BOs4Ordered B of tetrahedral composition4O15And (4) units. The oxides of the invention thus have two different catalytically active sites, BO6And BO4The synergistic catalytic effect can obviously improve the OER catalytic performance.
The invention provides an oxide with a hexagonal structure, which has a general structural formula A8B4O15Wherein A is one or more of rare earth metal elements or alkaline earth metal elements, and B is one or more of transition metal elements.
In one embodiment, the element A is preferably one or more of Ba, Sr, La, Pr, Nd, Sm, Gd and Eu, and the element B is preferably one or more of Co, Fe, Mn and Ni.
In one embodiment, the above formula A is preferred8B4O15Is Ba4Sr4Co4O15、Ba4Sr4Co3.2Fe0.8O15、Ba4Sr4Mn4O15、Ba3.5Sr3.5LaCo4O15、Ba3Sr3La2Co4O15、Ba6La2Co4O15、Ba4Sr4Fe4O15、Ba6La2Fe4O15Or Ba6Pr2Fe4O15。
The catalyst material can be synthesized by a sol-gel method, and can also be synthesized by a solid-phase reaction method, a coprecipitation method, a combustion method, a hydrothermal method, a microwave method and other conventional methods. The preparation method of the electrocatalyst material of the invention is described by the synthesis example of ethylenediamine tetraacetic acid (EDTA) -Citric Acid (CA) sol-gel combined complexation method.
According to the target product A8B4O15Weighing various raw material nitrates (analytically pure) in stoichiometric ratio according to the element proportion of the chemical formula, dissolving the raw material nitrates in water by heating, and dissolving the raw material nitrates in the stoichiometric ratio in the water according to the total number of metal ions: EDTA: respectively weighing EDTA and CA according to the amount that the citric acid (molar ratio) =1:1:2, dissolving the EDTA in ammonia water, stirring to completely dissolve the EDTA, pouring the EDTA into a prepared nitrate solution, adding the citric acid, adjusting the pH value of the solution to 6-8 by using the ammonia water, heating and stirring to form transparent sol, further treating the sol at the temperature of 200-300 ℃ to obtain a precursor, and finally roasting the precursor at the temperature of 900-1100 ℃ for 2-20 hours to obtain the required A8B4O15And (3) material powder.
The catalyst prepared by the invention is used for preparing an electrode and evaluating the Oxygen Evolution (OER) catalytic performance of the electrode, and the process is as follows:
1. preparation of catalyst slurry: a is to be8B4O15Powder and a certain amount of electric conductionMixing carbon black (the mass fraction of the conductive carbon black is 10-90%, the conductive carbon black plays the role of a conductive carrier and has almost no catalytic action) and dispersing the carbon black in ethanol or other organic solvents, adding a proper amount of Nafion (the mass fraction is 5%) solution into the mixture, wherein the concentration of the catalyst is 1-10 mg/mL, and the concentration of Nafion in the solution is 0.2-2 mg/mL, and then carrying out ultrasonic oscillation to uniformly mix the mixture to obtain the slurry for preparing the catalyst.
2. Preparing an electrode: transferring a certain amount of the prepared catalyst slurry onto a Rotating Disk Electrode (RDE) by using a micro-injector to ensure that the loading capacity of the catalyst slurry on the RDE is 0.1-1 mg/cm2And then naturally drying in air.
3. Measurement of electrode activity: the prepared electrodes were mounted on a rotating disk apparatus (Pine company) to perform electrochemical tests.
The procedure for the test is probably as follows:
1) the electrochemical test system is a three-electrode system (a glassy carbon electrode is a working electrode, a platinum sheet or a platinum wire is a counter electrode, Ag/AgCl is a reference electrode), and the electrolyte is 0.1mol/L KOH solution.
2) Before testing, continuously introducing oxygen into the reactor for 30-60 min to ensure that the electrolyte solution is saturated by oxygen, wherein the flow rate of the introduced oxygen is 150-250 mL/min. Oxygen was also kept on during the test.
3) The Oxygen Evolution (OER) catalytic activity was evaluated by conducting a polarization curve test (LSV) with a voltage sweep range of 0.2-1V, a sweep rate of 5 mV/s and a rotation speed of 1600 rpm.
4) Evaluation of catalytic stability, a constant current test (fixed 10 mA cm)-2Constant) the voltage was observed as a function of time to investigate catalyst stability.
The catalyst designed by the invention comprises but is not limited to the catalyst in the following examples, and the preparation method comprises but is not limited to the preparation method in the following examples.
Example 1 Ba4Sr4Co4O15Preparation of catalyst and evaluation of oxygen evolution catalytic Performance
Ba4Sr4Co4O15The catalyst powder is synthesized by a sol-gel combined complexing method. Separately weighing stoichiometric ratio of Ba (NO)3)2(analytically pure), Sr (NO)3)2(analytically pure), Co (NO)3)2·6H2Dissolving O (analytically pure) in water, heating to dissolve, and then according to the total number of metal ions: EDTA: respectively weighing EDTA and citric acid according to the amount that the citric acid (molar ratio) =1:1:2, dissolving the EDTA in ammonia water, stirring to completely dissolve the EDTA, pouring the EDTA into a prepared nitrate solution, adding the citric acid, adjusting the pH value of the solution to 7 by using the ammonia water, heating and stirring to form transparent sol, further treating the sol at the temperature of 250 ℃ to obtain a precursor, and finally roasting the precursor at the temperature of 1000 ℃ for 10 hours to obtain the required Ba4Sr4Co4O15And (3) catalyst powder. The X-ray diffraction (XRD) pattern shown in FIG. 2 indicates Ba4Sr4Co4O15A hexagonal structure is formed.
And evaluating the oxygen precipitation catalytic performance of the catalyst. Weighing 10 mg of Ba4Sr4Co4O15The catalyst and 10 mg of conductive carbon black (Super P) are dispersed in 1 mL of ethanol, 0.1 mL of Nafion (mass fraction 5%) solution is added thereto, and the mixture is uniformly mixed by ultrasonic oscillation for 1 h to obtain a catalyst slurry. Then, 5. mu.L of the catalyst slurry was transferred by a micro-syringe to a Rotating Disk Electrode (RDE) having a diameter of 5 mm, and the catalyst slurry was naturally dried in the air for 1 hour. The obtained electrode is subjected to oxygen evolution catalysis performance evaluation according to the electrode testing process in the invention. Commercial RuO2Catalyst and Ba4Sr4Co4O15The catalyst is subjected to electrode preparation and oxygen precipitation catalysis performance test under the same condition.
FIG. 3 shows Ba prepared in example 14Sr4Co4O15Catalyst and commercial RuO2Catalyst in O2A comparison of polarization curves in a saturated 0.1mol/L KOH solution reveals Ba4Sr4Co4O15Catalyst and commerceRuO of (2)2The catalyst has lower overpotential (0.75V @10 mA cm) than that of the catalyst-2vs. 0.79 V@10 m A cm-2) And higher current density (34.4 mA cm)-2@ 1 V vs. 23.9 m A cm-2@ 1V), description of Ba4Sr4Co4O15The catalyst has high-efficiency oxygen precipitation catalytic activity. FIG. 4 shows Ba in example 14Sr4Co4O15Catalyst and commercial RuO2Catalyst in O2A comparison of the stabilities in a saturated 0.1 mol/LKOH solution reveals that Ba is present4Sr4Co4O15Catalyst and commercial RuO2The catalyst showed less potential increase (13 mV vs. 120 mV), indicating Ba4Sr4Co4O15The catalyst has higher oxygen evolution operation stability.
The above experimental data show that Ba prepared in example 14Sr4Co4O15The catalyst has excellent oxygen precipitation catalytic performance and operation stability, and is superior to commercial noble metal oxide RuO2The catalyst can replace a commercial noble metal catalyst.
Example 2 Ba4Sr4Co3.2Fe0.8O15Preparation of catalyst and evaluation of oxygen evolution catalytic Performance
Ba4Sr4Co3.2Fe0.8O15The catalyst powder is synthesized by a sol-gel combined complexing method. Separately weighing stoichiometric ratio of Ba (NO)3)2(analytically pure), Sr (NO)3)2(analytically pure), Co (NO)3)2·6H2O (analytically pure), Fe (NO)3)3·9H2Dissolving O (analytically pure) in water, heating to dissolve, and then according to the total number of metal ions: EDTA: respectively weighing EDTA and CA according to the molar ratio of citric acid (mole ratio) =1:1: 2), dissolving EDTA in ammonia water, stirring to completely dissolve EDTA, pouring EDTA into prepared nitrate solution, adding citric acid, adjusting pH value of the solution to 7 with ammonia water, heating and stirring to form transparent sol, further heating the sol at 250 deg.CProcessing in a temperature range to obtain a precursor, and finally roasting the precursor at 1000 ℃ for 10 h to obtain the required Ba4Sr4Co3.2Fe0.8O15And (3) catalyst powder. The X-ray diffraction (XRD) pattern shown in FIG. 5 indicates Ba4Sr4Co3.2Fe0.8O15A hexagonal structure is formed.
And evaluating the oxygen precipitation catalytic performance of the catalyst. The electrode preparation and electrode testing procedures were the same as in example 1. FIG. 6 shows Ba prepared in example 24Sr4Co3.2Fe0.8O15Catalyst in O2Polarization diagram in saturated 0.1mol/L KOH solution at an oxygen evolution current density of 10 mA cm-2The overpotential is 0.71V, and the excellent oxygen evolution catalytic performance is shown; FIG. 7 shows Ba prepared in example 24Sr4Co3.2Fe0.8O15Catalyst in O2Stability profile in saturated 0.1mol/L KOH solution, which shows: the oxygen catalysis performance is stable, and the potential does not change obviously in 3600 s operation.
Example 3 Ba3.5Sr3.5LaCo4O15Preparation of catalyst and evaluation of oxygen evolution catalytic Performance
Ba3.5Sr3.5LaCo4O15The catalyst powder is synthesized by a sol-gel combined complexing method. Separately weighing stoichiometric ratio of Ba (NO)3)2(analytically pure), Sr (NO)3)2(analytically pure), La (NO)3)3·6H2O (analytically pure) and Co (NO)3)2·6H2Dissolving O (analytically pure) in water, heating to dissolve, and then according to the total number of metal ions: EDTA: respectively weighing EDTA and citric acid according to the amount that the citric acid (molar ratio) =1:1:2, dissolving the EDTA in ammonia water, stirring to completely dissolve the EDTA, pouring the EDTA into a prepared nitrate solution, adding the citric acid, adjusting the pH value of the solution to 7 by using the ammonia water, heating and stirring to form transparent sol, further treating the sol at the temperature of 250 ℃ to obtain a precursor, and finally roasting the precursor at the temperature of 1000 ℃ for 10 hours to obtain the required Ba3.5Sr3.5LaCo4O15And (3) catalyst powder. The X-ray diffraction (XRD) pattern shown in FIG. 8 indicates Ba3.5Sr3.5LaCo4O15A hexagonal structure is formed.
And evaluating the oxygen precipitation catalytic performance of the catalyst. The electrode preparation and electrode testing procedures were the same as in example 1. FIG. 9 shows Ba prepared in example 33.5Sr3.5LaCo4O15Catalyst in O2Polarization diagram in saturated 0.1mol/L KOH solution at an oxygen evolution current density of 10 mA cm-2The overpotential is 0.79V, and the excellent oxygen evolution catalytic performance is shown; FIG. 10 shows Ba prepared in example 33.5Sr3.5LaCo4O15Catalyst in O2Stability profile in saturated 0.1mol/L KOH solution, which shows: the oxygen catalysis performance is stable, and the potential does not change obviously in 3600 s operation.
Example 4: ba4Sr4Fe4O15Preparation of catalyst and evaluation of oxygen evolution catalytic Activity
Ba4Sr4Fe4O15The catalyst powder is synthesized by an EDTA-CA sol-gel combined complexing method. Separately weighing stoichiometric ratio of Ba (NO)3)2(analytically pure), Sr (NO)3)2(analytically pure), Fe (NO)3)3·9H2Dissolving O (analytically pure) in water, heating to dissolve, and then according to the total number of metal ions: EDTA: respectively weighing EDTA and citric acid according to the amount that the citric acid (molar ratio) =1:1:2, dissolving the EDTA in ammonia water, stirring to completely dissolve the EDTA, pouring the EDTA into a prepared nitrate solution, adding the citric acid, adjusting the pH value of the solution to 7 by using the ammonia water, heating and stirring to form transparent sol, further treating the sol at the temperature of 250 ℃ to obtain a precursor, and finally roasting the precursor at the temperature of 1000 ℃ for 10 hours to obtain the required Ba4Sr4Fe4O15And (3) catalyst powder. The X-ray diffraction (XRD) pattern shown in FIG. 11 indicates Ba4Sr4Fe4O15A hexagonal structure is formed.
Evaluation of oxygen evolution catalytic activity of the catalyst. The electrode preparation and electrode testing procedures were the same as in example 1. FIG. 12 is Ba prepared in example 44Sr4Fe4O15Catalyst in O2The polarization profile in a saturated 0.1mol/L KOH solution was found to be Ba4Sr4Fe4O15The catalyst has good oxygen precipitation catalytic activity and the current density of oxygen precipitation is 10 mA cm-2The overpotential was 0.86V.
Comparative example 1: conventional BO6Hexahedral material Ba0.5Sr0.5FeO3Preparation of catalyst and evaluation of oxygen evolution catalytic Activity
Ba0.5Sr0.5FeO3The catalyst powder is synthesized by an EDTA-CA sol-gel combined complexing method. Separately weighing stoichiometric ratio of Ba (NO)3)2(analytically pure), Sr (NO)3)2(analytically pure), Fe (NO)3)3·9H2Dissolving O (analytically pure) in water, heating to dissolve, and then according to the total number of metal ions: EDTA: respectively weighing EDTA and citric acid according to the amount that the citric acid (molar ratio) =1:1:2, dissolving the EDTA in ammonia water, stirring to completely dissolve the EDTA, pouring the EDTA into a prepared nitrate solution, adding the citric acid, adjusting the pH value of the solution to 7 by using the ammonia water, heating and stirring to form transparent sol, further treating the sol at the temperature of 250 ℃ to obtain a precursor, and finally roasting the precursor at the temperature of 1000 ℃ for 10 hours to obtain the required Ba0.5Sr0.5FeO3And (3) catalyst powder. The X-ray diffraction (XRD) pattern shown in FIG. 13 indicates Ba0.5Sr0.5FeO3A conventional cubic perovskite structure is formed.
Evaluation of oxygen evolution catalytic activity of the catalyst. The electrode preparation and electrode testing procedures were the same as in example 1. FIG. 14 shows a conventional cubic Ba prepared in comparative example 10.5Sr0.5FeO3Catalyst and hexagonal Ba4Sr4Fe4O15Catalyst in O2The polarization curve comparison chart in the saturated 0.1 mol/LKOH solution can find that the hexagonal Ba is4Sr4Fe4O15Catalyst and conventional cubic Ba0.5Sr0.5FeO3The catalyst has lower overpotential (0.86V @10 mA cm) than that of the catalyst-2vs. 0.97 V@10 m Acm-2) And higher current density (21.3 m A cm)-2@ 1 V vs. 11.8 m A cm-2@ 1V), description of hexagonal Ba4Sr4Fe4O15Catalyst and conventional cubic Ba0.5Sr0.5FeO3Compared with the catalyst, the catalyst has higher oxygen precipitation catalytic activity and shows the superiority of a hexagonal structure.

Claims (3)

1. The preparation method of the oxide with the hexagonal structure is characterized in that the structural general formula of the oxide with the hexagonal structure is A8B4O15The element A is one or more of Ba, Sr, La, Pr, Nd, Sm, Gd and Eu, and the element B is one or more of Co, Fe, Mn and Ni; the preparation method comprises the following steps: dissolving nitrates of the element A and the element B in water according to a stoichiometric ratio to obtain an aqueous solution; dissolving EDTA in ammonia water, adding the EDTA into the aqueous solution, adding citric acid and ammonia water to adjust the pH value to 6-8, wherein the metal ions of the element A and the element B: EDTA: the molar ratio of citric acid is 1:1: 2; heating and stirring to form transparent sol, carrying out heat treatment on the sol, and roasting to obtain the catalyst.
2. The method according to claim 1, wherein the hexagonal oxide is Ba4Sr4Co4O15、Ba4Sr4Co3.2Fe0.8O15、Ba4Sr4Mn4O15、Ba3.5Sr3.5LaCo4O15、Ba3Sr3La2Co4O15、Ba6La2Co4O15、Ba4Sr4Fe4O15、Ba6La2Fe4O15Or Ba6Pr2Fe4O15。
3. The method for producing an oxide having a hexagonal structure according to claim 1, wherein the heat treatment temperature is 200 to 300 ℃; the roasting temperature is 900-1100 ℃, and the roasting time is 2-20 h.
CN201810326691.2A 2018-04-12 2018-04-12 Oxide with hexagonal structure, preparation method and application thereof in oxygen evolution reaction Active CN108435178B (en)

Priority Applications (2)

Application Number Priority Date Filing Date Title
CN202010942624.0A CN112191242B (en) 2018-04-12 2018-04-12 Use of oxide with hexagonal structure in oxygen evolution reaction
CN201810326691.2A CN108435178B (en) 2018-04-12 2018-04-12 Oxide with hexagonal structure, preparation method and application thereof in oxygen evolution reaction

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201810326691.2A CN108435178B (en) 2018-04-12 2018-04-12 Oxide with hexagonal structure, preparation method and application thereof in oxygen evolution reaction

Related Child Applications (1)

Application Number Title Priority Date Filing Date
CN202010942624.0A Division CN112191242B (en) 2018-04-12 2018-04-12 Use of oxide with hexagonal structure in oxygen evolution reaction

Publications (2)

Publication Number Publication Date
CN108435178A CN108435178A (en) 2018-08-24
CN108435178B true CN108435178B (en) 2020-10-02

Family

ID=63199731

Family Applications (2)

Application Number Title Priority Date Filing Date
CN201810326691.2A Active CN108435178B (en) 2018-04-12 2018-04-12 Oxide with hexagonal structure, preparation method and application thereof in oxygen evolution reaction
CN202010942624.0A Active CN112191242B (en) 2018-04-12 2018-04-12 Use of oxide with hexagonal structure in oxygen evolution reaction

Family Applications After (1)

Application Number Title Priority Date Filing Date
CN202010942624.0A Active CN112191242B (en) 2018-04-12 2018-04-12 Use of oxide with hexagonal structure in oxygen evolution reaction

Country Status (1)

Country Link
CN (2) CN108435178B (en)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114772552A (en) * 2022-03-23 2022-07-22 浙江浙能技术研究院有限公司 Structured oxygen carrier for hydrogen production by chemical chain methane reforming and preparation method thereof

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN100339160C (en) * 2005-06-17 2007-09-26 中国科学院大连化学物理研究所 Preparation method of perovskite type metal oxide catalyst
JP2015221843A (en) * 2014-05-22 2015-12-10 パナソニック株式会社 Fluophor and light-emitting device using the same
CN105056961B (en) * 2015-07-28 2017-09-05 南京航空航天大学 Perovskite composite catalyst that amorphous non-noble metal hydroxide for oxygen evolution reaction is modified and preparation method thereof
CN105964265B (en) * 2016-06-27 2018-07-03 陕西科技大学 A kind of Magnetoplumbate-type CH4-CO2The preparation method of reforming catalyst
CN107866214A (en) * 2017-11-17 2018-04-03 中国矿业大学 A kind of chemical solution method prepares Ca3Bi8O15The method of film

Also Published As

Publication number Publication date
CN112191242B (en) 2023-05-26
CN108435178A (en) 2018-08-24
CN112191242A (en) 2021-01-08

Similar Documents

Publication Publication Date Title
CN108579751B (en) Layered perovskite oxide, preparation method and application thereof in oxygen evolution reaction electrocatalysis
CN109759077B (en) Perovskite oxide catalyst and preparation method and application thereof
CN108325565B (en) Multi-functional carbon-based base metal elctro-catalyst of one kind and its preparation method and application
CN108923051A (en) A kind of nitrogen-doped carbon nanometer pipe composite catalyst of package metals cobalt nano-particle and its application
CN107604375A (en) Difunctional VPO catalysts of the porous carbon complex of nitrogen cobalt codope and its preparation method and application
CN111001428B (en) Metal-free carbon-based electrocatalyst, preparation method and application
CN102867965A (en) Porous microsphere perovskite type calcium manganese oxide compound and preparation method and application thereof
CN113235104A (en) ZIF-67-based lanthanum-doped cobalt oxide catalyst and preparation method and application thereof
CN111389411A (en) Perovskite electrocatalyst and preparation method and application thereof
CN113718270A (en) Carbon-supported NiO/NiFe2O4Preparation method and application of spinel type solid solution water electrolysis oxygen evolution catalyst
WO2024066179A1 (en) Surface-modified perovskite oxide electrocatalyst as well as preparation method therefor and use thereof
CN109234762A (en) Catalyst and its preparation method and application, water decomposition system
CN108435178B (en) Oxide with hexagonal structure, preparation method and application thereof in oxygen evolution reaction
CN102867966A (en) Porous micro-sphere post-spinel nitride calcium manganese oxygen compound, and preparation of and application thereof
CN113174609B (en) Preparation method and application of ultrahigh-performance hydrogen evolution water electrolysis catalyst
CN102658152B (en) Method for preparing oxygen electrode perovskite-type catalyst
CN111686729B (en) Perovskite type carbon dioxide electro-reduction catalyst and preparation method thereof
CN114086196B (en) Oxygen evolution perovskite catalyst with low overpotential and high stability and preparation method thereof
CN114361480B (en) Method for preparing electrode material of zinc-air battery by xerogel method
CN115786964B (en) Cobalt-based spinel Cu 0.7 Co 2.3 O 4 Electrocatalyst, preparation method and application thereof
CN112778535B (en) Preparation method and application of multi-element heterogeneous metal organic framework material
CN115652357B (en) Sulfur-doped yttrium ruthenate, preparation method thereof and oxygen evolution reaction electrode
CN117604556A (en) Preparation method and application of double-phase composite anode catalyst for seawater electrolysis hydrogen production
CN116024603A (en) BiFeO 3 Preparation method and application of perovskite catalytic electrode
CN116470074A (en) Molybdenum-doped anti-perovskite nitride three-dimensional self-supporting material and preparation method and application thereof

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
GR01 Patent grant
GR01 Patent grant