Foamed nickel-loaded iron-cobalt-nickel metal nano-catalyst and preparation method and application thereof

Abstract

The invention discloses a foamed nickel-loaded iron-cobalt-nickel metal nano-catalyst and a preparation method and application thereof. The method comprises the following steps: cutting foamed nickel,washing and drying for later use; dissolving three metal salts of cobalt nitrate, ferrous nitrate and nickel nitrate, ammonium fluoride and urea into deionized water; performing stirring to obtain ahydrothermal solution; then adding the pretreated foamed nickel and the prepared hydrothermal solution into a high-pressure reaction kettle, vertically putting the foamed nickel into the bottom of thehigh-pressure reaction kettle after the foamed nickel is inserted into a polytetrafluoroethylene base, fastening the high-pressure reaction kettle, putting the high-pressure reaction kettle into a blast drying oven, carrying out first-step hydrothermal treatment, performing cooling to room temperature, performing washing and drying to obtain an intermediate product; and putting the prepared precursor into a reaction kettle, carrying out a second-step hydrothermal reaction, performing cooling to room temperature, and performing washing and drying. The preparation method provided by the invention has good economy and environmental protection property, and the prepared product has excellent electro-catalytic oxygen evolution performance, high strength and good stability, and can be applied to the field of water electrolysis oxygen evolution.

Description

technical field

[0001] The invention relates to the technical field of electrode materials, in particular to a foamed nickel-supported iron-cobalt-nickel metal nano-catalyst and a preparation method and application thereof. Background technique

[0002] As an ideal clean energy, hydrogen energy is considered to be one of the energy sources with broad development prospects in the future. In recent years, in order to minimize the cost of hydrogen production by electrolysis of water, a large number of researchers have developed a variety of low-cost and high-efficiency catalysts. The best anode oxygen evolution catalyst for water electrolysis is the noble metal iridium-based catalyst, but the high cost obviously cannot meet the large-scale hydrogen production demand in the future. There have been many reports on the use of low-cost and cheap metal catalysts as oxygen evolution electrodes.

[0003] Transition metal compounds (oxides, hydroxides, phosphides, and sulfides, etc....

Examples

Embodiment 1

[0024] A preparation method for foamed nickel-supported iron-cobalt-nickel metal nano-catalysts, comprising the following steps:

[0025] (1) Pretreatment of foamed nickel: Cut the foamed nickel into a rectangle with a size of 1 cm×4.5 cm, soak the foamed nickel in 3M HCl, acetone, absolute ethanol and deionized water in sequence for ultrasonic cleaning, each cleaning 10 min, dry and ready for use;

[0026] (2) Add 2 mmol Co(NO 3 ) 2 ·6H 2 O, 6 mmol NH 4 F, 12 mmol urea and 1 mmol Ni(NO 3 ) 2 ·6H 2 The mixture of O was dissolved in 60 mL deionized water to obtain a mixed solution and stirred for 30 min, and the first step hydrothermal solution was obtained after stirring evenly;

[0027](3) Insert the pretreated nickel foam into the PTFE mold base with slots to keep the nickel foam in a vertical state, add 100 mL of the PTFE base inserted into the foam nickel and the prepared hydrothermal solution In the autoclave, nickel foam is fixed vertically at the bottom of the a...

Embodiment 2

[0031] With embodiment 1, the difference is that in the step (2) Ni(NO 3 ) 2 ·6H 2 The amount of O added was 0.75 mmol, and 0.25 mmol of Fe(NO 3 ) 2 9H 2 O. The X-ray diffraction pattern of the prepared electrode can be found in figure 2 In (b) curve, the material structure of this nickel foam surface loading is mainly amorphous.

[0032] The electrode obtained in this example is at 50 mA·cm -2 The oxygen evolution overpotential at a current density of 277 mV.

Embodiment 3

[0034] With embodiment 1, the difference is that in the step (2) Ni(NO 3 ) 2 ·6H 2 The amount of O added was 0.5 mmol, and 0.5 mmol of Fe(NO 3 ) 2 9H 2 O. Scanning electron microscope (SEM) pictures of the fabricated electrodes can be found in figure 1 , it can be seen from the figure that the material presents a beam-like structure, which is conducive to the electron transfer of the oxygen evolution reaction and the removal of the product oxygen, which is conducive to the oxygen evolution reaction. The X-ray diffraction pattern of the prepared electrode can be found in figure 2 In (c) curve, the material structure supported on the surface of this nickel foam is mainly amorphous and low crystallinity Co 5 (O 9.48 h 8.52 )NO 3 .

[0035] The electrode obtained in this example is at 50 mA·cm -2 The oxygen evolution overpotential at a high current density is 228 mV, and at a high current density of 100 mA cm -2 The lower overpotential is still very low at 250 mV. ...

technical field

[0001] The invention relates to the technical field of electrode materials, in particular to a foamed nickel-supported iron-cobalt-nickel metal nano-catalyst and a preparation method and application thereof. Background technique

[0002] As an ideal clean energy, hydrogen energy is considered to be one of the energy sources with broad development prospects in the future. In recent years, in order to minimize the cost of hydrogen production by electrolysis of water, a large number of researchers have developed a variety of low-cost and high-efficiency catalysts. The best anode oxygen evolution catalyst for water electrolysis is the noble metal iridium-based catalyst, but the high cost obviously cannot meet the large-scale hydrogen production demand in the future. There have been many reports on the use of low-cost and cheap metal catalysts as oxygen evolution electrodes.

[0003] Transition metal compounds (oxides, hydroxides, phosphides, and sulfides, etc....

Examples

Embodiment 1

[0024] A preparation method for foamed nickel-supported iron-cobalt-nickel metal nano-catalysts, comprising the following steps:

[0025] (1) Pretreatment of foamed nickel: Cut the foamed nickel into a rectangle with a size of 1 cm×4.5 cm, soak the foamed nickel in 3M HCl, acetone, absolute ethanol and deionized water in sequence for ultrasonic cleaning, each cleaning 10 min, dry and ready for use;

[0026] (2) Add 2 mmol Co(NO 3 ) 2 ·6H 2 O, 6 mmol NH 4 F, 12 mmol urea and 1 mmol Ni(NO 3 ) 2 ·6H 2 The mixture of O was dissolved in 60 mL deionized water to obtain a mixed solution and stirred for 30 min, and the first step hydrothermal solution was obtained after stirring evenly;

[0027](3) Insert the pretreated nickel foam into the PTFE mold base with slots to keep the nickel foam in a vertical state, add 100 mL of the PTFE base inserted into the foam nickel and the prepared hydrothermal solution In the autoclave, nickel foam is fixed vertically at the bottom of the a...

Embodiment 2

[0031] With embodiment 1, the difference is that in the step (2) Ni(NO 3 ) 2 ·6H 2 The amount of O added was 0.75 mmol, and 0.25 mmol of Fe(NO 3 ) 2 9H 2 O. The X-ray diffraction pattern of the prepared electrode can be found in figure 2 In (b) curve, the material structure of this nickel foam surface loading is mainly amorphous.

[0032] The electrode obtained in this example is at 50 mA·cm -2 The oxygen evolution overpotential at a current density of 277 mV.

Embodiment 3

[0034] With embodiment 1, the difference is that in the step (2) Ni(NO 3 ) 2 ·6H 2 The amount of O added was 0.5 mmol, and 0.5 mmol of Fe(NO 3 ) 2 9H 2 O. Scanning electron microscope (SEM) pictures of the fabricated electrodes can be found in figure 1 , it can be seen from the figure that the material presents a beam-like structure, which is conducive to the electron transfer of the oxygen evolution reaction and the removal of the product oxygen, which is conducive to the oxygen evolution reaction. The X-ray diffraction pattern of the prepared electrode can be found in figure 2 In (c) curve, the material structure supported on the surface of this nickel foam is mainly amorphous and low crystallinity Co 5 (O 9.48 h 8.52 )NO 3 .

[0035] The electrode obtained in this example is at 50 mA·cm -2 The oxygen evolution overpotential at a high current density is 228 mV, and at a high current density of 100 mA cm -2 The lower overpotential is still very low at 250 mV. ...

Images