A Co3S4 / FeCo2S4 / NF nanocomposite material, its preparation method and application
Co3S4/FeCo2S4 nanocomposite materials were prepared by hydrothermal method and sulfidation treatment, which solved the problem of low catalytic activity of electrocatalytic hydrogen production materials and achieved a high-efficiency improvement in electrocatalytic hydrogen production performance.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- CHANGSHA UNIVERSITY OF SCIENCE AND TECHNOLOGY
- Filing Date
- 2024-01-11
- Publication Date
- 2026-06-23
Smart Images
Figure CN117867573B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of electrocatalytic hydrogen production materials, specifically to a Co3S4 / FeCo2S4 / NF nanocomposite material, its preparation method, and its application. Background Technology
[0002] Hydrogen energy, recognized worldwide as a clean energy source, has received widespread attention in low-carbon and zero-carbon energy initiatives. Hydrogen boasts a high energy density, making it an ideal alternative to fossil fuels. Hydrogen production through water electrolysis is environmentally friendly, and given the abundance of water resources on Earth, water splitting driven by electricity or solar energy is a highly efficient method for hydrogen production.
[0003] However, direct hydrogen production via water electrolysis has a high potential (1.23V) and high energy consumption. It is necessary to develop efficient and inexpensive catalysts to promote the hydrogen production reaction and reduce the hydrogen production potential via water electrolysis. Existing electrocatalytic hydrogen production technologies generally suffer from low catalytic activity and low performance of electrode materials. Summary of the Invention
[0004] To address the shortcomings of the existing technologies, the present invention aims to provide a Co3S4 / FeCo2S4 / NF nanocomposite material, its preparation method, and its applications. The present invention employs a sulfidation method to sulfide Co3O4 / FeCo2O4 grown on nickel foam, converting the oxides into the corresponding sulfides. By optimizing the process parameters, the structure and interface of the Co3S4 / FeCo2S4 / NF nanocomposite material can be effectively controlled, thereby improving its electrocatalytic hydrogen production activity.
[0005] To solve the above-mentioned technical problems, the present invention adopts the following technical solution:
[0006] A method for preparing a Co3S4 / FeCo2S4 / NF nanocomposite material includes the following steps:
[0007] Soluble iron salt, soluble cobalt salt, NH4F and urea are reacted with water to obtain reaction solution one;
[0008] Nickel foam was added to the reaction solution, and the mixture was heated to react. After cooling, the mixture was washed and dried to obtain the FeCo2O4 / NF precursor. The FeCo2O4 / NF precursor was then heat-treated to obtain FeCo2O4 / NF.
[0009] Soluble cobalt salt, NH4F, and urea are reacted with water to obtain reaction solution two. The FeCo2O4 / NF is added to reaction solution two and subjected to a hydrothermal reaction. The mixture is then cooled to room temperature, washed, and dried to obtain a Co3O4 precursor. The Co3O4 precursor is then subjected to heat treatment to obtain Co3O4 / FeCo2O4 / NF.
[0010] Co3O4 / FeCo2O4 / NF was subjected to sulfidation treatment in thioacetamide solution to obtain Co3S4 / FeCo2S4 / NF nanocomposite material.
[0011] In a preferred embodiment of the present invention, the soluble iron salt is FeCl2·4H2O and the soluble cobalt salt is CoCl2·6H2O.
[0012] In a preferred embodiment of the present invention, the molar ratio of FeCl2·4H2O, CoCl2·6H2O, urea and NH4F in reaction solution one is 1:2:8:6, and the mass ratio of the soluble iron salt to the volume ratio of water is 0.199g:34mL.
[0013] In a preferred embodiment of the present invention, the hydrothermal reaction temperature is 110–150°C and the hydrothermal reaction time is 7–9 h.
[0014] In a preferred embodiment of the present invention, the vulcanization temperature is 160°C and the vulcanization time is 10-14 hours.
[0015] In a preferred embodiment of the present invention, the heat treatment temperature of the FeCo2O4 / NF precursor and the Co3O4 precursor is 300-400℃, and the heat treatment time is 2-4h.
[0016] In a preferred embodiment of the present invention, the molar ratio of CoCl2·6H2O, NH4F and urea in reaction solution two is 1:1:6, and the mass ratio of CoCl2·6H2O to the volume ratio of water is 0.238g:17mL.
[0017] Another object of the present invention is to provide a Co3S4 / FeCo2S4 / NF nanocomposite material prepared by any of the above preparation methods.
[0018] The third objective of this invention is to provide an application of the aforementioned Co3S4 / FeCo2S4 / NF nanocomposite material in electrocatalytic hydrogen production electrode materials.
[0019] Compared with the prior art, the beneficial effects of the present invention are:
[0020] 1. This invention utilizes the spinel structure and excellent properties of Co3S4 and FeCo2S4 to prepare a Co3S4 / FeCo2S4 / NF nanocomposite material on nickel foam by hydrothermal method, heat treatment and sulfidation method, FeCl2·4H2O, CoCl2·6H2O, urea, NH4F and thioacetamide, thereby constructing a high-performance novel electrocatalytic hydrogen production nanocomposite material.
[0021] 2. This invention first employs a hydrothermal method to prepare a reaction solution from FeCl2·4H2O, CoCl2·6H2O, urea, and NH4F. Then, a FeCo2O4 / NF precursor is synthesized on nickel foam. This precursor is then heated to prepare a FeCo2O4 / NF matrix. The FeCo2O4 / NF matrix is added to the reaction solution and subjected to a hydrothermal reaction at different temperatures and times. A Co3O4 precursor is prepared on the FeCo2O4 / NF matrix and subjected to a heating reaction to obtain Co3O4 / FeCo2O4 / NF. Finally, Co3O4 / FeCo2O4 / NF undergoes a hydrothermal reaction in a thioacetamide solution to obtain a Co3S4 / FeCo2S4 / NF nanocomposite material. This composite material is used as an electrode material for electrocatalytic hydrogen production. Its electrocatalytic hydrogen production performance is tested in both three-electrode and two-electrode systems, which is beneficial for expanding the application of the Co3S4 / FeCo2S4 / NF nanocomposite material in the field of electrocatalytic hydrogen production.
[0022] 3. Both Co3S4 and FeCo2S4 are spinel structure materials with good cycle performance during electrode charge-discharge processes. They also possess excellent properties such as low cost, environmental friendliness, electrochemical durability, and high catalytic activity. Combining these two materials leverages their respective advantages and effectively modulates their interface to achieve more efficient electrocatalytic hydrogen production. In typical ACo2S4 (A=Co,Fe) spinel structure oxides, 32 oxygen atoms are closely packed into tetrahedral and octahedral structures. A has a +2 valence, occupying the oxygen tetrahedral voids, while Co has a +3 valence, occupying the sulfur octahedral voids. This provides abundant active sites for the electrocatalytic hydrogen production reaction. Combining Co3S4 and FeCo2S4 to construct nanocomposite materials can fully utilize the advantages of both materials, synergistically improving the electrocatalytic hydrogen production performance of the nanocomposite materials during the electrocatalytic hydrogen production reaction.
[0023] 4. This invention combines Co3S4 and FeCo2S4 nanomaterials using a relatively simple hydrothermal method, heat treatment, and sulfidation. The preparation process is easy to implement and can effectively control the structure and interface of the Co3S4 / FeCo2S4 / NF nanocomposite material. By continuously optimizing the interface structure, the synergistic effect between Co3S4 and FeCo2S4 can be fully utilized. After the two are combined, the specific surface area increases, providing more active sites for electrochemical reactions and significantly improving the electrocatalytic hydrogen production performance of the Co3S4 / FeCo2S4 / NF nanocomposite material, effectively solving the problem of low activity in electrocatalytic hydrogen production materials. Attached Figure Description
[0024] Figure 1XRD patterns of Co3O4, FeCo2O4, Co3O4@FeCo2O4 and Co3S4@FeCo2S4 samples prepared for this invention: Figure (a) shows the XRD patterns of Co3O4, FeCo2O4, 110-7 and 150-7, with the patterns from top to bottom being 110-7, 150-7, FeCo2O4 and Co3O4; Figure (b) shows the XRD patterns of Co3S4@FeCo2S4 obtained by sulfiding 110-7 for 14 h and 150-7 for 14 h, with the patterns from top to bottom being 150-7 for 14 h and 110-7 for 14 h.
[0025] Figure 2 SEM images of Co3O4@FeCo2O4 and Co3S4@FeCo2S4 prepared for this invention: (a), (b), (c), and (d) are SEM images of 110-7; (e), (f), (g), and (h) are SEM images of Co3S4@FeCo2S4 obtained by sulfidation in 110-7 for 14 h.
[0026] Figure 3 EDS diagrams of Co3O4@FeCo2O4 and Co3S4@FeCo2S4 prepared for this invention: Figure (a) is the EDS diagram of 110-7; Figure (b) is the EDS diagram of Co3S4@FeCo2S4 obtained by sulfidation of 110-7 for 14 h.
[0027] Figure 4 This is a comparison of the hydrogen evolution (HER) curves of the Co3O4@FeCo2O4 nanocomposite material prepared in this invention and a single sample. The vertical axis, Crett density, represents the current density (mA / cm²). 2 The horizontal axis Cell Voltage represents the device voltage (V), where 1 represents Co3O4, 2 represents FeCo2O4, and 3 represents Co3O4@FeCo2O4.
[0028] Figure 5 This is a comparison of the hydrogen evolution (HER) curves of the (a)Co3S4@FeCo2S4 nanocomposite material prepared in this invention and a single sample. The vertical axis, Crett density, represents the current density (mA / cm²). 2 (a) The horizontal axis CellVoltage represents the device voltage (V), where 1 represents 110-7, 2 represents 130-7, 3 represents 130-9, and 4 represents 150-7; (b) Tafel curve, the vertical axis Overvoltage represents the device overpotential (V), and the vertical axis Log(jmA / cm) represents the device overpotential. 2 ) represents the logarithm of the current density, where 1 represents 110⁻⁷, 2 represents 130⁻⁷, 3 represents 130⁻⁹, and 4 represents 150⁻⁷.
[0029] Figure 6 The hydrogen production HER curves of the Co3O4@FeCo2O4 nanocomposite material prepared in this invention and the Co3S4@FeCo2S4 nanocomposite material obtained after sulfidation are compared. In this paper, 1 represents 110-7 and 2 represents 110-7 sulfidation for 14 h.
[0030] Figure 7 The C of the Co3S4@FeCo2S4 nanocomposite material prepared in this invention dl Capacitance, with the vertical axis representing current density (mA / cm²). 2 The horizontal axis Scanrate represents the scanning speed (mV / s).
[0031] Figure 8 Impedance curves of the Co3S4@FeCo2S4 nanocomposite prepared for this invention: (a) at different curing times, the horizontal axis Z′ represents the real part of the impedance (Ohm), and the vertical axis Z″ represents the imaginary part of the impedance (Ohm); (b) comparison of impedance curves before and after 110-7 curing, the horizontal axis Z′ represents the real part of the impedance (Ohm), and the vertical axis Z″ represents the imaginary part of the impedance (Ohm).
[0032] Figure 9 The vertical axis of the it curve for the Co3O4@FeCo2O4 and Co3S4@FeCo2S4 nanocomposites prepared in this invention represents the current density (mA / cm). 2 The horizontal axis, Time, represents time (s). Detailed Implementation
[0033] The following detailed description, in conjunction with embodiments of the present invention and accompanying drawings, provides a clear and complete illustration of the technical solutions in these embodiments. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.
[0034] It should be noted that all technical terms used in this invention are for the purpose of describing specific embodiments only and are not intended to limit the scope of protection of this invention. Unless otherwise specified, all raw materials, reagents, instruments and equipment used in the following embodiments of this invention can be purchased from the market or prepared by existing methods.
[0035] Example 1
[0036] A method for preparing a Co3S4 / FeCo2S4 / NF nanocomposite material includes the following steps:
[0037] (1) Weigh 1 mmol FeCl2·4H2O (0.199 g), 2 mmol CoCl2·6H2O (0.476 g), 8 mmol urea (0.480 g), and 6 mmol NH4F (0.222 g) using an electronic balance and place them in a beaker. Weigh 34 mL of deionized water using a graduated cylinder and add it to the beaker. The solution turns magenta. Place a magnetic stir bar in the beaker and stir for 30 min. The solution turns orange. Stop stirring to obtain reaction solution one. Distribute reaction solution one evenly into the inner liner of two 25 mL reaction vessels and add 1 cm x 1 cm nickel foam treated with concentrated hydrochloric acid to each vessel. (2cm), then tighten the reaction vessel and place it in a drying test chamber for reaction at 120℃ for 6h. After the reaction vessel is naturally cooled to room temperature, the foamed nickel is carefully washed three times with ethanol and deionized water in turn, and dried at 60℃ for 12h to obtain FeCo2O4 / NF precursor. Then the FeCo2O4 / NF precursor is placed in a porcelain boat and annealed in a muffle furnace at 400℃ for 2h. After the annealing is completed, the sample is taken out to obtain FeCo2O4 / NF sample, which is then bagged for later use.
[0038] (2) Weigh 1 mmol CoCl2·6H2O (0.238 g), 1 mmol NH4F (0.037 g) and 6 mmol urea (0.360 g) into a beaker using an electronic balance. Measure 17 mL of deionized water into the beaker. The solution is pink. Place a magnetic stir bar into the beaker and stir for 30 min. The solution color does not change significantly. Stop stirring to obtain reaction solution two. Pour reaction solution two into the inner liner of a 25 mL reaction vessel and add FeCo2O4 / NF (1 cm x 2 cm) prepared in step (1). Then tighten the reaction vessel and place it in a drying test chamber for reaction. Set the temperature to 110 °C and the time to 7 h.
[0039] (3) After the reaction is complete, the reactor is naturally cooled to room temperature, the waste liquid is poured out, the nickel foam is carefully washed three times with ethanol and deionized water, and dried at 60°C for 12 hours to obtain the Co3O4 precursor. The Co3O4 precursor is then placed in a porcelain boat and annealed in a muffle furnace at 400°C for 2 hours. After the annealing is completed, the sample is taken out to obtain Co3O4 / FeCo2O4 / NF (1cm x 2cm), which is then bagged and stored for later use, and is recorded as 110-7.
[0040] (4) Weigh 0.1g of thioacetamide using an electronic balance and put it into a beaker. Weigh 50mL of deionized water using a graduated cylinder and pour it into the beaker. Place a magnetic stir bar in the beaker and stir it on a magnetic stirrer for 10min.
[0041] (5) After stirring, take 35 mL of the solution and pour it into a 50 mL reaction vessel. Add the prepared 110-7 (1 cm x 2 cm) composite sample to it. Then tighten the reaction vessel and put it into a drying test chamber for reaction at 160 °C for 10 h.
[0042] (6) After the reaction was completed, the reactor was naturally cooled to room temperature, the nickel foam was carefully washed three times with deionized water, and dried at 60°C for 12 hours to obtain Co3S4 / FeCo2S4 / NF nanocomposite material. After the reaction was completed, the sample was taken out and bagged for later use.
[0043] Example 2
[0044] A method for preparing a Co3S4 / FeCo2S4 / NF nanocomposite material includes the following steps:
[0045] (1) Weigh 1 mmol FeCl2·4H2O (0.199 g), 2 mmol CoCl2·6H2O (0.476 g), 8 mmol urea (0.480 g), and 6 mmol NH4F (0.222 g) using an electronic balance and place them in a beaker. Weigh 34 mL of deionized water using a graduated cylinder and add it to the beaker. The solution turns magenta. Place a magnetic stir bar in the beaker and stir for 30 min. The solution turns orange. Stop stirring to obtain reaction solution one. Distribute reaction solution one evenly into the inner liner of two 25 mL reaction vessels and add 1 cm x 1 cm nickel foam treated with concentrated hydrochloric acid to each vessel. (2cm), then tighten the reaction vessel and place it in a drying test chamber for reaction at 120℃ for 6h. After the reaction vessel is naturally cooled to room temperature, the foamed nickel is carefully washed three times with ethanol and deionized water in turn, and dried at 60℃ for 12h to obtain FeCo2O4 / NF precursor. Then the FeCo2O4 / NF precursor is placed in a porcelain boat and annealed in a muffle furnace at 400℃ for 2h. After the annealing is completed, the sample is taken out to obtain FeCo2O4 / NF sample, which is then bagged for later use.
[0046] (2) Weigh 1 mmol CoCl2·6H2O (0.238 g), 1 mmol NH4F (0.037 g) and 6 mmol urea (0.360 g) into a beaker using an electronic balance. Measure 17 mL of deionized water into the beaker. The solution is pink. Place a magnetic stir bar into the beaker and stir for 30 min. The solution color does not change significantly. Stop stirring to obtain reaction solution two. Pour reaction solution two into the inner liner of a 25 mL reaction vessel and add FeCo2O4 / NF (1 cm x 2 cm) prepared in step (1). Then tighten the reaction vessel and place it in a drying test chamber for reaction. Set the temperature to 110 °C and the time to 7 h.
[0047] (3) After the reaction is complete, the reactor is naturally cooled to room temperature, the waste liquid is poured out, the nickel foam is carefully washed three times with ethanol and deionized water, and dried at 60°C for 12 hours to obtain the Co3O4 precursor. The Co3O4 precursor is then placed in a porcelain boat and annealed in a muffle furnace at 400°C for 2 hours. After the annealing is completed, the sample is taken out to obtain Co3O4 / FeCo2O4 / NF (1cm x 2cm), which is then bagged and stored for later use, and is recorded as 110-7.
[0048] (4) Weigh 0.1g of thioacetamide using an electronic balance and put it into a beaker. Weigh 50mL of deionized water using a graduated cylinder and pour it into the beaker. Place a magnetic stir bar in the beaker and stir it on a magnetic stirrer for 10min.
[0049] (5) After stirring, take 35 mL of the solution and pour it into a 50 mL reaction vessel. Add the prepared 110-7 (1 cm x 2 cm) composite sample to it. Then tighten the reaction vessel and put it into a drying test chamber for reaction at 160 °C for 14 h.
[0050] (6) After the reaction is completed, the reaction vessel is naturally cooled to room temperature. The foamed nickel is carefully washed three times with deionized water and dried at 60°C for 12 hours to obtain Co3S4 / FeCo2S4 / NF nanocomposite material. After the reaction is completed, the sample is taken out and bagged for later use.
[0051] Example 3
[0052] A method for preparing a Co3S4 / FeCo2S4 / NF nanocomposite material includes the following steps:
[0053] (1) Weigh 1 mmol FeCl2·4H2O (0.199 g), 2 mmol CoCl2·6H2O (0.476 g), 8 mmol urea (0.480 g), and 6 mmol NH4F (0.222 g) using an electronic balance and place them in a beaker. Weigh 34 mL of deionized water using a graduated cylinder and add it to the beaker. The solution turns magenta. Place a magnetic stir bar in the beaker and stir for 30 min. The solution turns orange. Stop stirring to obtain reaction solution one. Distribute reaction solution one evenly into the inner liner of two 25 mL reaction vessels and add 1 cm x 1 cm nickel foam treated with concentrated hydrochloric acid to each vessel. (2cm), then tighten the reaction vessel and place it in a drying test chamber for reaction at 120℃ for 6h. After the reaction vessel is naturally cooled to room temperature, the foamed nickel is carefully washed three times with ethanol and deionized water in turn, and dried at 60℃ for 12h to obtain FeCo2O4 / NF precursor. Then the FeCo2O4 / NF precursor is placed in a porcelain boat and annealed in a muffle furnace at 400℃ for 2h. After the annealing is completed, the sample is taken out to obtain FeCo2O4 / NF sample, which is then bagged for later use.
[0054] (2) Weigh 1 mmol CoCl2·6H2O (0.238 g), 1 mmol NH4F (0.037 g) and 6 mmol urea (0.360 g) into a beaker using an electronic balance. Measure 17 mL of deionized water into the beaker. The solution is pink. Place a magnetic stir bar into the beaker and stir for 30 min. The solution color does not change significantly. Stop stirring to obtain reaction solution two. Pour reaction solution two into the inner liner of a 25 mL reaction vessel and add FeCo2O4 / NF (1 cm x 2 cm) prepared in step (1). Then tighten the reaction vessel and place it in a drying test chamber for reaction. Set the temperature to 130 °C and the time to 7 h.
[0055] (3) After the reaction is complete, the reactor is naturally cooled to room temperature, the waste liquid is poured out, the nickel foam is carefully washed three times with ethanol and deionized water, and dried at 60°C for 12 hours to obtain the Co3O4 precursor. The Co3O4 precursor is then placed in a porcelain boat and annealed in a muffle furnace at 400°C for 2 hours. After the annealing is completed, the sample is taken out to obtain Co3O4 / FeCo2O4 / NF (1cm x 2cm), which is then bagged and stored for later use, and is recorded as 130-7.
[0056] (4) Weigh 0.1g of thioacetamide using an electronic balance and put it into a beaker. Weigh 50mL of deionized water using a graduated cylinder and pour it into the beaker. Place a magnetic stir bar in the beaker and stir it on a magnetic stirrer for 10min.
[0057] (5) After stirring, take 35 mL of the solution and pour it into a 50 mL reaction vessel. Add the prepared 110-7 (1 cm x 2 cm) composite sample to it. Then tighten the reaction vessel and put it into a drying test chamber for reaction at 160 °C for 10 h.
[0058] (6) After the reaction was completed, the reactor was naturally cooled to room temperature, the nickel foam was carefully washed three times with deionized water, and dried at 60°C for 12 hours to obtain Co3S4 / FeCo2S4 / NF nanocomposite material. After the reaction was completed, the sample was taken out and bagged for later use.
[0059] Example 4
[0060] A method for preparing a Co3S4 / FeCo2S4 / NF nanocomposite material includes the following steps:
[0061] (1) Weigh 1 mmol FeCl2·4H2O (0.199 g), 2 mmol CoCl2·6H2O (0.476 g), 8 mmol urea (0.480 g), and 6 mmol NH4F (0.222 g) using an electronic balance and place them in a beaker. Weigh 34 mL of deionized water using a graduated cylinder and add it to the beaker. The solution turns magenta. Place a magnetic stir bar in the beaker and stir for 30 min. The solution turns orange. Stop stirring to obtain reaction solution one. Distribute reaction solution one evenly into the inner liner of two 25 mL reaction vessels and add 1 cm x 1 cm nickel foam treated with concentrated hydrochloric acid to each vessel. (2cm), then tighten the reaction vessel and place it in a drying test chamber for reaction at 120℃ for 6h. After the reaction vessel is naturally cooled to room temperature, the foamed nickel is carefully washed three times with ethanol and deionized water in turn, and dried at 60℃ for 12h to obtain FeCo2O4 / NF precursor. Then the FeCo2O4 / NF precursor is placed in a porcelain boat and annealed in a muffle furnace at 400℃ for 2h. After the annealing is completed, the sample is taken out to obtain FeCo2O4 / NF sample, which is then bagged for later use.
[0062] (2) Weigh 1 mmol CoCl2·6H2O (0.238 g), 1 mmol NH4F (0.037 g) and 6 mmol urea (0.360 g) into a beaker using an electronic balance. Measure 17 mL of deionized water into the beaker. The solution is pink. Place a magnetic stir bar into the beaker and stir for 30 min. The solution color does not change significantly. Stop stirring to obtain reaction solution two. Pour reaction solution two into the inner liner of a 25 mL reaction vessel and add FeCo2O4 / NF (1 cm x 2 cm) prepared in step (1). Then tighten the reaction vessel and place it in a drying test chamber for reaction. Set the temperature to 130 °C and the time to 9 h.
[0063] (3) After the reaction is complete, the reactor is naturally cooled to room temperature, the waste liquid is poured out, the nickel foam is washed three times with ethanol and deionized water in turn, and dried at 60°C for 12 hours to obtain the Co3O4 precursor. Then the Co3O4 precursor is placed in a porcelain boat and annealed in a muffle furnace at 400°C for 2 hours. After the annealing is completed, the sample is taken out to obtain Co3O4 / FeCo2O4 / NF, which is then bagged and stored for later use, and is recorded as 130-9.
[0064] (4) Weigh 0.1g of thioacetamide using an electronic balance and put it into a beaker. Weigh 50mL of deionized water using a graduated cylinder and pour it into the beaker. Place a magnetic stir bar in the beaker and stir it on a magnetic stirrer for 10min.
[0065] (5) After stirring, take 35 mL of the solution and pour it into a 50 mL reaction vessel. Add the prepared 110-7 (1 cm x 2 cm) composite sample to it. Then tighten the reaction vessel and put it into a drying test chamber for reaction at 160 °C for 10 h.
[0066] (6) After the reaction was completed, the reactor was naturally cooled to room temperature, the nickel foam was carefully washed three times with deionized water, and dried at 60°C for 12 hours to obtain Co3S4 / FeCo2S4 / NF nanocomposite material. After the reaction was completed, the sample was taken out and bagged for later use.
[0067] Example 5
[0068] A method for preparing a Co3S4 / FeCo2S4 / NF nanocomposite material includes the following steps:
[0069] (1) Weigh 1 mmol FeCl2·4H2O (0.199 g), 2 mmol CoCl2·6H2O (0.476 g), 8 mmol urea (0.480 g), and 6 mmol NH4F (0.222 g) using an electronic balance and place them in a beaker. Weigh 34 mL of deionized water using a graduated cylinder and add it to the beaker. The solution turns magenta. Place a magnetic stir bar in the beaker and stir for 30 min. The solution turns orange. Stop stirring to obtain reaction solution one. Distribute reaction solution one evenly into the inner liner of two 25 mL reaction vessels and add 1 cm x 1 cm nickel foam treated with concentrated hydrochloric acid to each vessel. (2cm), then tighten the reaction vessel and place it in a drying test chamber for reaction at 120℃ for 6h. After the reaction vessel is naturally cooled to room temperature, the foamed nickel is carefully washed three times with ethanol and deionized water in turn, and dried at 60℃ for 12h to obtain FeCo2O4 / NF precursor. Then the FeCo2O4 / NF precursor is placed in a porcelain boat and annealed in a muffle furnace at 350℃ for 4h. After the annealing is completed, the sample is taken out to obtain FeCo2O4 / NF sample, which is then bagged for later use.
[0070] (2) Weigh 1 mmol CoCl2·6H2O (0.238 g), 1 mmol NH4F (0.037 g) and 6 mmol urea (0.360 g) into a beaker using an electronic balance. Measure 17 mL of deionized water into the beaker using a graduated cylinder. The solution is pink. Place a magnetic stir bar into the beaker and stir for 30 min. The solution color does not change significantly. Stop stirring to obtain reaction solution two. Pour reaction solution two into the inner liner of a 25 mL reaction vessel and add FeCo2O4 / NF (1 cm x 2 cm) prepared in step (1). Then tighten the reaction vessel and place it in a drying test chamber for reaction. Set the temperature to 150 °C and the time to 7 h.
[0071] (3) After the reaction is complete, the reactor is naturally cooled to room temperature, the waste liquid is poured out, the nickel foam is carefully washed three times with ethanol and deionized water, and dried at 60°C for 12 hours to obtain the Co3O4 precursor. The Co3O4 precursor is then placed in a porcelain boat and annealed in a muffle furnace at 400°C for 2 hours. After the annealing is completed, the sample is taken out to obtain Co3O4 / FeCo2O4 / NF (1cm x 2cm), which is then bagged and stored for later use, and is recorded as 150-7.
[0072] (4) Weigh 0.1g of thioacetamide using an electronic balance and put it into a beaker. Weigh 50mL of deionized water using a graduated cylinder and pour it into the beaker. Place a magnetic stir bar in the beaker and stir it on a magnetic stirrer for 10min.
[0073] (5) After stirring, take 35 mL of the solution and pour it into a 50 mL reaction vessel. Add the prepared 110-7 (1 cm x 2 cm) composite sample to it. Then tighten the reaction vessel and put it into a drying test chamber for reaction at 160 °C for 10 h.
[0074] (6) After the reaction is completed, the reaction vessel is naturally cooled to room temperature. The foamed nickel is carefully washed three times with deionized water and dried at 60°C for 12 hours to obtain Co3S4 / FeCo2S4 / NF nanocomposite material. After the reaction is completed, the sample is taken out and bagged for later use.
[0075] Example 6
[0076] A method for preparing a Co3S4 / FeCo2S4 / NF nanocomposite material includes the following steps:
[0077] (1) Weigh 1 mmol FeCl2·4H2O (0.199 g), 2 mmol CoCl2·6H2O (0.476 g), 8 mmol urea (0.480 g), and 6 mmol NH4F (0.222 g) using an electronic balance and place them in a beaker. Weigh 34 mL of deionized water using a graduated cylinder and add it to the beaker. The solution turns magenta. Place a magnetic stir bar in the beaker and stir for 30 min. The solution turns orange. Stop stirring to obtain reaction solution one. Distribute reaction solution one evenly into the inner liner of two 25 mL reaction vessels and add 1 cm x 1 cm nickel foam treated with concentrated hydrochloric acid to each vessel. (2cm), then tighten the reaction vessel and place it in a drying test chamber for reaction at 120℃ for 6h. After the reaction vessel is naturally cooled to room temperature, the foamed nickel is carefully washed three times with ethanol and deionized water in turn, and dried at 60℃ for 12h to obtain FeCo2O4 / NF precursor. Then the FeCo2O4 / NF precursor is placed in a porcelain boat and annealed in a muffle furnace at 300℃ for 3h. After the annealing is completed, the sample is taken out to obtain FeCo2O4 / NF sample, which is then bagged for later use.
[0078] (2) Weigh 1 mmol CoCl2·6H2O (0.238 g), 1 mmol NH4F (0.037 g) and 6 mmol urea (0.360 g) into a beaker using an electronic balance. Measure 17 mL of deionized water into the beaker. The solution is pink. Place a magnetic stir bar into the beaker and stir for 30 min. The solution color does not change significantly. Stop stirring to obtain reaction solution two. Pour reaction solution two into the inner liner of a 25 mL reaction vessel and add FeCo2O4 / NF (1 cm x 2 cm) prepared in step (1). Then tighten the reaction vessel and place it in a drying test chamber for reaction. Set the temperature to 110 °C and the time to 7 h.
[0079] (3) After the reaction is complete, the reactor is naturally cooled to room temperature, the waste liquid is poured out, the nickel foam is carefully washed three times with ethanol and deionized water, and dried at 60°C for 12 hours to obtain the Co3O4 precursor. The Co3O4 precursor is then placed in a porcelain boat and annealed in a muffle furnace at 400°C for 2 hours. After the annealing is completed, the sample is taken out to obtain Co3O4 / FeCo2O4 / NF (1cm x 2cm), which is then bagged and stored for later use, and is recorded as 110-7.
[0080] (4) Weigh 0.1g of thioacetamide using an electronic balance and put it into a beaker. Weigh 50mL of deionized water using a graduated cylinder and pour it into the beaker. Place a magnetic stir bar in the beaker and stir it on a magnetic stirrer for 10min.
[0081] (5) After stirring, take 35 mL of the solution and pour it into a 50 mL reaction vessel. Add the prepared 110-7 (1 cm x 2 cm) composite sample to it. Then tighten the reaction vessel and put it into a drying test chamber for reaction at 160 °C for 14 h.
[0082] (6) After the reaction is completed, the reaction vessel is naturally cooled to room temperature. The foamed nickel is carefully washed three times with deionized water and dried at 60°C for 12 hours to obtain Co3S4 / FeCo2S4 / NF nanocomposite material. After the reaction is completed, the sample is taken out and bagged for later use.
[0083] Comparative Example 1
[0084] A method for preparing a Co3O4 / FeCo2O4 / NF nanocomposite material includes the following steps:
[0085] (1) Weigh 1 mmol FeCl2·4H2O (0.199 g), 2 mmol CoCl2·6H2O (0.476 g), 8 mmol urea (0.480 g), and 6 mmol NH4F (0.222 g) using an electronic balance and place them in a beaker. Weigh 34 mL of deionized water using a graduated cylinder and add it to the beaker. The solution turns magenta. Place a magnetic stir bar in the beaker and stir for 30 min. The solution turns orange. Stop stirring to obtain reaction solution one. Distribute reaction solution one evenly into the inner liner of two 25 mL reaction vessels and add 1 cm x 1 cm nickel foam treated with concentrated hydrochloric acid to each vessel. (2cm), then tighten the reaction vessel and place it in a drying test chamber for reaction at 120℃ for 6h. After the reaction vessel is naturally cooled to room temperature, the foamed nickel is carefully washed three times with ethanol and deionized water in turn, and dried at 60℃ for 12h to obtain FeCo2O4 / NF precursor. Then the FeCo2O4 / NF precursor is placed in a porcelain boat and annealed in a muffle furnace at 400℃ for 2h. After the annealing is completed, the sample is taken out to obtain FeCo2O4 / NF sample, which is then bagged for later use.
[0086] (2) Weigh 1 mmol CoCl2·6H2O (0.238 g), 1 mmol NH4F (0.037 g) and 6 mmol urea (0.360 g) into a beaker using an electronic balance. Measure 17 mL of deionized water into the beaker. The solution is pink. Place a magnetic stir bar into the beaker and stir for 30 min. The solution color does not change significantly. Stop stirring to obtain reaction solution two. Pour reaction solution two into the inner liner of a 25 mL reaction vessel and add FeCo2O4 / NF (1 cm x 2 cm) prepared in step (1). Then tighten the reaction vessel and place it in a drying test chamber for reaction. Set the temperature to 110 °C and the time to 7 h.
[0087] (3) After the reaction is complete, the reactor is naturally cooled to room temperature, the waste liquid is poured out, the nickel foam is washed three times with ethanol and deionized water in turn, and dried at 60°C for 12 hours to obtain the Co3O4 precursor. Then the Co3O4 precursor is placed in a porcelain boat and annealed in a muffle furnace at 400°C for 2 hours. After the annealing is completed, the sample is taken out to obtain Co3O4 / FeCo2O4 / NF, which is bagged for later use and recorded as 110-7.
[0088] Results and Analysis
[0089] like Figure 1 As shown, Figure 1(a) Shows the XRD patterns of FeCo2O4, Co3O4, 110-7Co3O4@FeCo2O4, and 150-7Co3O4@FeCo2O4 samples. The two strong reflection peaks at 44.5° and 51.8° are peaks of nickel foam, while the peaks at 31.3°, 36.9°, 59.4°, and 65.2° are generated by Co3O4, corresponding to the (220), (311), and (51) peaks of spinel-structured Co3O4, respectively. The peaks at 31.2°, 37.0°, 55.3°, 59.0°, and 64.9° of the (1) and (440) crystal planes correspond to the spinel-like (220), (311), (422), (511), and (440) crystal planes of FeCo2O4. After the two are combined, the peaks at 18.6° and 55.3° are very weak or even almost disappear. This may be because the diffraction peaks of FeCo2O4 are weakened by the Co3O4 covering its surface. Figure 1 Figure (b) shows the XRD pattern of the Co3S4@FeCo2S4 sample obtained after the vulcanization of the Co3O4@FeCo2O4 composite material. The two strong diffraction peaks at 44.7° and 52.1° are the peaks of nickel foam. The peaks at 38.1°, 50.1° and 55.6° are the peaks of the spinel structure of the Co3S4@FeCo2S4 composite material. Since both Co3S4 and FeCo2S4 are spinel structures, their XRD peaks are quite similar. In fact, FeCo2S4 can be regarded as the partial replacement of Co element with Fe in Co3S4.
[0090] like Figure 2 The image shows the SEM images of 110-7 and 150-7 prepared in the examples after 14 hours of sulfidation. As can be seen from the image, FeCo2O4 nanorods grow on the surface of the nickel foam, with Co3O4 nanorods interwoven with FeCo2O4, forming a porous and relatively stable structure. The interlacing of the nanorods increases the electrochemically active reaction sites and improves catalytic efficiency. For the sulfidated Co3S4@FeCo2S4 nanocomposite material, obvious sulfidated nanosheets of Co3S4@FeCo2S4 composite material appear on the nanorods on the surface of the nickel foam. These nanosheets are interconnected, forming a porous and complex structure.
[0091] like Figure 3 As shown, the embodiment is... Figure 3 (a) shows the area scanned to obtain 110-7 and the... Figure 3(b) shows the EDS spectrum of the 150-7 sulfurized composite material after 14 hours of sulfidation. Analysis of the Co3O4@FeCo2O4 composite material shows that it contains Fe, Co, and O elements, and their distribution is relatively uniform. Analysis of the sulfurized Co3S4@FeCo2S4 composite material shows that Fe, Co, and S elements are evenly distributed.
[0092] like Figure 4 As shown in the examples, the HER behavior of the Co3O4@FeCo2O4 composite material and the single sample clearly demonstrates that the composite sample exhibits superior catalytic performance. At 10 mA / cm², 2 At current densities of 10 mA / cm², the voltages required for single Co3O4, single FeCo2O4, and Co3O4@FeCo2O4 composite materials are 2.078 V, 2.075 V, and 2.007 V, respectively. The figure clearly shows that the potential required for the Co3O4@FeCo2O4 composite material is significantly lower than that for the FeCo2O4 and Co3O4 single samples, and this decreases with increasing current density, starting from 10 mA / cm². 2 Up to 25mA / cm 2 The overpotential of the Co3O4@FeCo2O4 composite sample was consistently lower than that of the single FeCo2O4 and Co3O4 materials. This demonstrates that the Co3O4@FeCo2O4 composite material exhibits superior catalytic performance compared to the single FeCo2O4 and Co3O4 materials.
[0093] like Figure 5 As shown in the embodiment Figure 5 (a) shows the HER curves of hydrogen production for four composite samples, 110-7, 130-7, 130-9, and 150-7, in a 1 mol / L KOH electrolyte, which demonstrates the electrocatalytic performance of the composite material. Figure 5 (a) It can be seen that the composite samples of 110-7 and 150-7 exhibit superior catalytic hydrogen production performance in water electrolysis. This is achieved at a current density of 20 mA / cm². 2 At the specified times, the overpotentials were 307mV, 370mV, 364mV, and 345mV, respectively, indicating that the 110-7 and 150-7 composite materials exhibited better performance and higher catalytic activity. With increasing current density, the overpotentials of the 110-7 and 150-7 composite materials remained consistently lower than those of the 130-7 and 130-9 composite materials. Figure 5(b) The Tafel slope of each Co3O4@FeCo2O4 composite sample. The Tafel slope of the Co3O4@FeCo2O4(110-7) composite catalyst is 152 mV / dec. In comparison, the Tafel slopes of samples 130-7, 130-9 and 150-7 are 335 mV / dec, 308 mV / dec and 158 mV / dec, respectively. It can be seen that the composite sample with the best electrocatalytic performance is the one that has been hydrothermally heated at 110℃ for 7 h.
[0094] like Figure 6 As shown in the embodiment Figure 6 This is a comparison graph of the LSV of the 110-7 composite sample and the sample that has undergone further vulcanization for 14 hours, at a current density of 20 mA / cm². 2 When the overpotentials were 307mV and 247mV respectively, it can be seen that the catalytic performance of hydrogen evolution through water electrolysis of the sulfided sample was further improved.
[0095] like Figure 7 As shown in the embodiment Figure 7 The image shows the Cdl plot of the Co3S4@FeCo2S4 composite material sample after composite vulcanization. The Co3S4@FeCo2S4 composite material sample obtained by vulcanization at 110-7 for 10 h has a strength of 29.8 mF / cm³. 2 The value is greater than 150-7 after 10 hours of sulfidation (23.6 mF / cm). 2 ), 110-7 vulcanization for 14 hours, (18.5 mF / cm) 2 ) and a Co3S4@FeCo2S4 composite sample vulcanized at 150-7 for 14 hours (7.8 mF / cm) 2 This indicates that the Co3S4@FeCo2S4 composite material can provide more active sites for electrocatalytic hydrogen production reactions.
[0096] like Figure 8 As shown in the embodiment Figure 8 The impedance spectrum of the Co3S4@FeCo2S4 and Co3O4@FeCo2O4 composite materials is shown below. Figure 8 As can be seen from (a), sample 110-7, after 10 hours of vulcanization, has the lowest impedance. However, comparing sample 110-7 with it reveals... Figure 8 (b) clearly shows that the impedance of the sample after 10 hours of vulcanization is significantly lower than that of the unvulcanized composite sample.
[0097] like Figure 9 As shown in the embodiment Figure 9 The image shows the it curves for electrocatalytic hydrogen production of the Co3O4@FeCo2O4 and Co3S4@FeCo2S4 composite materials. Figure 9a represents the time-it curves of the Co3O4@FeCo2O4(110-7) composite material and the Co3S4@FeCo2S4 composite material obtained after 14 hours of vulcanization, tested under constant voltage for 24 hours. It can be seen that both the Co3O4@FeCo2O4 sample and the Co3S4@FeCo2S4 have good stability.
[0098] In summary, this invention employs a hydrothermal method to prepare a reaction solution from FeCl2·4H2O, CoCl2·6H2O, urea, and NH4F. A FeCo2O4 / NF precursor is then synthesized on nickel foam. This precursor is then heated to prepare the FeCo2O4 / NF matrix. The FeCo2O4 / NF matrix is added to the reaction solution and subjected to a hydrothermal reaction at different temperatures and times. A Co3O4 precursor is prepared on the FeCo2O4 / NF matrix and subjected to a heating reaction to obtain Co3O4 / FeCo2O4 / NF. Finally, Co3O4 / FeCo2O4 / NF undergoes a hydrothermal reaction in a thioacetamide solution to obtain a Co3S4 / FeCo2S4 / NF nanocomposite material. This composite material is used as an electrode material for electrocatalytic hydrogen production, and its electrocatalytic hydrogen production performance is tested in both three-electrode and two-electrode systems. This approach is beneficial for expanding the application of the Co3S4 / FeCo2S4 / NF nanocomposite material in the field of electrocatalytic hydrogen production.
[0099] Obviously, those skilled in the art can make various modifications and variations to this invention without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this invention and their equivalents, this invention also intends to include these modifications and variations.
Claims
1. A preparation method of a Co3S4 / FeCo2S4 / NF nanocomposite, characterized in that, Includes the following steps: Soluble iron salt, soluble cobalt salt, NH4F and urea are reacted with water to obtain reaction solution one; Nickel foam was added to the reaction solution and heated to obtain FeCo2O4 / NF precursor. The FeCo2O4 / NF precursor was then heat-treated to obtain FeCo2O4 / NF. The hydrothermal reaction temperature was 110–150°C and the hydrothermal reaction time was 7–9 h. The heat treatment temperature for both the FeCo2O4 / NF precursor and the Co3O4 precursor was 300–400°C and the heat treatment time was 2–4 h. Soluble cobalt salt, NH4F and urea are reacted with water to obtain reaction solution two. The FeCo2O4 / NF is added to reaction solution two and a hydrothermal reaction is carried out to obtain Co3O4 precursor. The Co3O4 precursor is heat-treated to obtain Co3O4 / FeCo2O4 / NF. Co3O4 / FeCo2O4 / NF was vulcanized in a thioacetamide solution to obtain a Co3S4 / FeCo2S4 / NF nanocomposite material; the vulcanization temperature was 160℃ and the vulcanization time was 10-14h.
2. The preparation method of the Co3S4 / FeCo2S4 / NF nanocomposite according to claim 1, characterized in that, The soluble iron salt is FeCl2·4H2O, and the soluble cobalt salt is CoCl2·6H2O.
3. The method for preparing Co3S4 / FeCo2S4 / NF nanocomposites according to claim 2, characterized in that, In reaction solution one, the molar ratio of FeCl2·4H2O, CoCl2·6H2O, urea and NH4F is 1:2:8:6, and the mass ratio of FeCl2·4H2O to water is 0.199g:34mL.
4. The method for preparing the Co3S4 / FeCo2S4 / NF nanocomposite material according to claim 2, characterized in that, In reaction solution 2, the molar ratio of CoCl2·6H2O, NH4F and urea is 1:1:6, and the mass ratio of CoCl2·6H2O to water is 0.238g:17mL.
5. A Co3S4 / FeCo2S4 / NF nanocomposite material prepared by the preparation method according to any one of claims 1-4.
6. The application of the Co3S4 / FeCo2S4 / NF nanocomposite material as described in claim 5 in electrocatalytic hydrogen production electrode materials.