Hydrogen peroxide modified nickel hydroxide composite sulfur indium zinc material as well as preparation method and application thereof

Abstract

The invention discloses a hydrogen peroxide modified nickel hydroxide composite sulfur indium zinc material as well as a preparation method and application thereof, and belongs to the technical field of photocatalytic hydrogen production catalysts. The nickel hydroxide composite sulfur-indium-zinc material is formed by compounding hydrogen peroxide modified nickel hydroxide and sulfur-indium-zinc. According to the invention, Ni (OH) 2 is modified by H2O2, the surface electronic structure of Ni (OH) 2 is changed, and the acting force between Ni (OH) 2 and ZnIn2S4 is increased, so that the transfer of photo-generated charges is accelerated, an innovative solution is provided for a high-efficiency and stable photocatalytic hydrogen production technology, the application prospect is obvious, under the illumination of AM 1.5, the hydrogen production rate is greater than or equal to 787 mu mol.g <-1 >. H <-1 >, the accumulated hydrogen production amount in four hours is greater than or equal to 3150 mu mol.g <-1 >, and the application prospect is wide. And the light absorption range is expanded to 570 nm.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of photocatalytic hydrogen production catalysts, and particularly relates to a hydrogen peroxide modified nickel hydroxide composite sulfur-indium-zinc material and a preparation method and application thereof. BACKGROUND

[0002] The energy consumption of flammable fuel oil has increased significantly, causing huge air and environmental pollution, and the reserves of flammable fuel oil are rapidly depleted. Due to these problems, hydrogen (H2) energy as a substitute clean energy with special heat value and abundant reserves has attracted extensive attention from the research community and plays a crucial role in promoting global carbon neutrality and sustainable development goals. Traditional hydrogen production methods, such as fossil fuel reforming and water electrolysis, generally face the problems of high energy consumption and large carbon emissions; under this background, photocatalytic hydrogen evolution (HER) has become a key technology for the transition to clean energy. Using particulate photocatalysts, especially using single light absorbers for photocatalytic water splitting, there are obvious thermodynamic and kinetic barriers in the process of chemical bond formation and breaking, which involves multi-electron transfer and proton transfer. A key research goal is to develop an efficient and stable photocatalytic system that can economically and effectively split water to produce hydrogen on a scale that meets global energy demand.

[0003] Photocatalytic hydrogen production technology is a pollution-free technology that operates under environmental conditions and sufficient sunlight. Photocatalysis is considered the most effective and sustainable technology for converting solar energy into chemical energy. The photocatalytic activity of this system is driven by high visible light absorption, charge separation, and photo-induced electron transfer to the surface. A lot of research has been done on the development of efficient photocatalysts. Most photocatalysts have limited visible light absorption / solar light collection capabilities, limiting their industrial applications. Two-dimensional layered ternary bimetallic semiconductors ZnIn2S4 (ZIS) based on chalcogenides have emerged in various photocatalytic applications due to their environmental safety, tunable band gap (2.06-2.85 eV), and chemical stability. However, the photoactivity of ZIS is severely limited by its rapid charge recombination and poor photoelectron acceleration ability, resulting in low photoactivity and stability.

[0004] Loading a cocatalyst Ni(OH)2 on the photocatalyst not only helps to enhance charge separation, but also provides abundant active sites to accelerate reaction kinetics. However, the nickel component often exists in the form of particles or simple mixing, which leads to weak interfacial interaction between it and sulfur-indium-zinc, making it difficult to fully exert the synergistic effect of the two. SUMMARY

[0005] Therefore, the present application aims to provide a hydrogen peroxide modified nickel hydroxide composite sulfur indium zinc material and a preparation method and application thereof.

[0006] In order to achieve the above-mentioned purpose, the present application provides the following technical solutions.

[0007] In the first aspect, the present application provides a hydrogen peroxide modified nickel hydroxide composite sulfur indium zinc material, characterized in that the hydrogen peroxide modified nickel hydroxide composite sulfur indium zinc material is composed of hydrogen peroxide modified nickel hydroxide and sulfur indium zinc.

[0008] Preferably, the mass ratio of the hydrogen peroxide modified nickel hydroxide to the sulfur indium zinc is (1-20):100.

[0009] Preferably, the preparation method of the hydrogen peroxide modified nickel hydroxide is as follows.

[0010] Ni(OH)2 and NaOH solution are mixed, then hydrogen peroxide solution is added dropwise, stirred at room temperature, and the precipitate is collected by centrifugation, washed with ultrapure water, and vacuum dried.

[0011] Preferably, the mass-volume ratio of the Ni(OH)2, NaOH solution and hydrogen peroxide solution is 0.2g:10mL:0.2ml.

[0012] Preferably, the concentration of the NaOH solution is 0.1mol / L, and the concentration of the hydrogen peroxide solution is 30% hydrogen peroxide solution.

[0013] Preferably, the stirring time at room temperature is 1h.

[0014] The band gap of Ni(OH)2 is large (about 3.0-3.2eV for α-Ni(OH)2 and about 3.3-3.5eV for β-Ni(OH)2), which belongs to ultraviolet light responsive materials, and can only absorb ultraviolet light with a wavelength <400nm (about 5% of solar spectrum), and has almost no response to visible light (400-760nm, about 43%), which limits the solar energy conversion efficiency. However, the Ni(OH)2 with layered crystal structure can accommodate water molecules or ions between the layers, and the surface is rich in hydroxyl groups (-OH). This structure not only can adsorb water molecules (reactants for photocatalytic hydrogen production) through the surface hydroxyl groups, but also can provide active sites for hydrogen evolution reaction (HER); at the same time, the electron transport path in the layer is relatively clear, which is helpful for charge separation and migration. The band gap of ZnIn2S4 is about 2.2-2.4eV, and the corresponding light absorption wavelength threshold is about 517-564nm, which can effectively cover the visible light region in the solar spectrum.

[0015] The present application constructs a nickel hydroxide / sulfur indium zinc (Ni(OH)2 / ZnIn2S4) heterojunction composite material to improve the performance of Ni(OH)2 in the photocatalytic hydrogen evolution reaction. By using hydrogen peroxide to modify Ni(OH)2, the oxidation reaction makes the surface rich in active hydroxyl groups (-OH), and the H2O generated by the decomposition of H2O2 can be adsorbed on the material surface through hydrogen bonds, significantly improving the surface hydrophilicity. In the photocatalytic hydrogen production, high hydrophilicity helps the rapid adsorption and activation of water molecules on the catalyst surface (H2O→H + +OH - ), providing sufficient proton source for HER. By compounding Ni(OH)2-H2O2 with ZnIn2S4, efficient charge separation, wide spectral response and anti-photo corrosion performance of the catalyst are realized, and finally a photocatalytic hydrogen production material with high activity and low cost is obtained, which provides an innovative solution for the large-scale application of solar-driven clean hydrogen production technology.

[0016] In a second aspect, the present application also provides a preparation method of the above-mentioned nickel hydroxide composite sulfur indium zinc material, comprising the following steps:

[0017] The hydrogen peroxide-modified nickel hydroxide, sulfur indium zinc, and deionized water are mixed for electrostatic self-assembly, and then the hydrogen peroxide-modified nickel hydroxide composite sulfur indium zinc material is obtained through centrifugal drying.

[0018] Preferably, the preparation method of the sulfur indium zinc is as follows:

[0019] The zinc acetate dihydrate, indium chloride tetrahydrate, thioacetamide, and ultrapure water are mixed and stirred for 0.5 hours, placed in a hydrothermal reaction kettle, and reacted at 180℃ for 12 hours, and then the sulfur indium zinc is obtained through centrifugation, washing, and drying.

[0020] Preferably, the molar ratio of the zinc acetate dihydrate, indium chloride tetrahydrate, and thioacetamide is 0.5:1:8.

[0021] In a third aspect, the present application provides the application of the above-mentioned nickel hydroxide composite sulfur indium zinc material in photocatalytic efficient hydrogen production.

[0022] At least the following beneficial technical effects are achieved:

[0023] The present application modifies Ni(OH)2 using H2O2, changes its surface electronic structure, increases the interaction between ZnIn2S4, and accelerates the photo-induced charge transfer, thereby providing an innovative solution for efficient and stable photocatalytic hydrogen production technology, which has a significant application prospect. Under AM 1.5 illumination, the hydrogen production rate is ≥787 μmol·g -1 ·h -1 , and the cumulative hydrogen production in four hours is ≥3150 μmol·g-1 The light absorption range was extended to 570 nm. BRIEF DESCRIPTION OF DRAWINGS

[0024] Figure 1 SEM images of ZIS (ZnIn2S4), Ni(OH)2, Ni(OH)2-H2O2, 10% Ni(OH)2-H2O2 / ZIS.

[0025] Figure 2 TEM, STEM-EDS of 10% Ni(OH)2-H2O2 / ZIS.

[0026] Figure 3 XRD of each monomer and each example preparation material.

[0027] Figure 4 Photocurrent response curves of each monomer and each example preparation material.

[0028] Figure 5 Electrochemical impedance spectra of each monomer and each example preparation material.

[0029] Figure 6 Photoluminescence spectra of each monomer and each example preparation material.

[0030] Figure 7 UV-Vis absorption spectra of each monomer and each example preparation material.

[0031] Figure 8 Surface charge characteristics of ZnIn2S4(ZIS), Ni(OH)2, and H2O2-treated Ni(OH)2(Ni(OH)2-H2O2) are shown.

[0032] Figure 9 Photocatalytic hydrogen production amount-time curves.

[0033] Figure 10 Hydrogen production rate bar graphs. DETAILED DESCRIPTION

[0034] Various illustrative embodiments of the present application are now described in detail below. The detailed description is made with reference to the accompanying drawings, wherein the same or like components have the same or like reference numbers. The present application should not be considered limited to the particular examples described herein, as such can vary. It is intended that the specification and illustrated embodiments be considered as exemplary only.

[0035] It is to be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the present application. In addition, where a range of values is provided, it is understood that each intervening value, to the upper and lower limit of the range is also specifically disclosed. Each smaller range between any stated value or intervening value in a stated range and any other stated or intervening value in that stated range is encompassed. The upper and lower limits of these smaller ranges can independently be included or excluded in the range, and are also encompassed by the application, subject to any specifically excluded limit in the stated range. Where the stated range includes one or both of the limits, ranges excluding either or both of those included limits are also included.

[0036] Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. Although any methods and materials similar or equivalent to those described herein can be used in the practice or testing of the present application, the preferred methods and materials are described. All patents, patent applications, publications, and descriptions mentioned herein are incorporated by reference to disclose and describe the methods and / or materials in connection with which the patents, patent applications, publications, and descriptions are cited.

[0037] Many modifications and variations of the present application described in the specification are possible without departing from the scope or spirit of the application. Other implementations of the application will be apparent to those skilled in the art from consideration of the specification and practice of the application disclosed herein. The specification and examples given are exemplary only. It is to be understood that the application is not limited in scope by the described embodiments.

[0038] As used herein, the terms "comprises", "comprising", "includes", "including", "has", "having", "contains", "containing", or variations thereof, are intended to be open-ended terms that mean inclusion, but not limited to, the listed materials and methods.

[0039] As used herein, the terms "room temperature", "ambient temperature" are intended to mean 25 ± 2 °C, unless otherwise specified.

[0040] The raw materials and instruments used in the following examples of the present application are commercially available, unless otherwise specified.

[0041] Preparation of raw materials:

[0042] Preparation of hydrogen peroxide modified nickel hydroxide:

[0043] 1.68 g of C2H4N4, 0.37 g of NH4F, and 1.0177 g of Ni(NO3)2·6H2O were weighed and dissolved in 70 mL of deionized water, and magnetic stirring was performed for 15 min to obtain a mixed solution; the solution was transferred to a 100 mL reaction kettle and placed in a constant temperature oven at 160 °C for 12 h of reaction, after the reaction kettle was naturally cooled to room temperature, the catalyst was taken out by opening the kettle body, washed with deionized water for 6 times, and dried in a 60 °C oven for 24 h to obtain Ni(OH)2.

[0044] Subsequently, 0.2 g of Ni(OH)2 was dissolved in 10 mL of 0.1 M NaOH solution, 0.2 mL of a hydrogen peroxide solution with a concentration of 30% was slowly added, stirring at room temperature for 1 h, the precipitate was collected by centrifugation, washed with water 3 times, and dried at 60°C under vacuum for 24 h to obtain Ni(OH)2-H2O2.

[0045] Preparation of zinc indium sulfide:

[0046] Zn(C2H3O2)2·2H2O (0.1097 g), InCl3·4H2O (0.2931 g), and TAA (0.6010 g) were dissolved in 50 mL of deionized water, and stirred vigorously for 30 min, and the resulting solution was sealed and placed in an oven at 180°C for 12 h, the yellow precipitate was collected by centrifugation, and washed with deionized water and anhydrous ethanol alternately 6 times, and dried in a vacuum freeze-drying device for 24 h to obtain ZnIn2S4.

[0047] Example

[0048] The present example provides a hydrogen peroxide modified nickel hydroxide composite zinc indium sulfide material, and the preparation method is as follows:

[0049] The ZnIn2S4 prepared above and Ni(OH)2-H2O2 were added to 10 mL of deionized water for mixing, and electrostatic self-assembly was performed by using the different surface electrical properties of the two. The mass of Ni(OH)2-H2O2 and ZnIn2S4 was matched according to Ni(OH)2-H2O2 accounting for 1%, 5%, 10%, 15%, and 20% of ZnIn2S4, and the samples were respectively marked as 1% Ni(OH)2-H2O2 / ZIS, 5% Ni(OH)2-H2O2 / ZIS, 10% Ni(OH)2-H2O2 / ZIS, 15% Ni(OH)2-H2O2 / ZIS, and 20% Ni(OH)2-H2O2 / ZIS. See Table 1 for details.

[0050] Table 1

[0051]

[0052] Experimental Example 1

[0053] The present application synthesizes two monomer materials by hydrothermal synthesis, modifies Ni(OH)2 using H2O2, and composites it with zinc indium sulfide to obtain a catalyst sample.

[0054] Figure 1The SEM images of ZIS (ZnIn2S4), Ni(OH)2, Ni(OH)2-H2O2, 10% Ni(OH)2-H2O2 / ZIS present the morphology characteristics of each material. As can be seen from the figure, ZIS (ZnIn2S4) is in the form of nanoflower, after treating Ni(OH)2 with H2O2, the mild oxidative etching makes the surface morphology of Ni(OH)2 change from smooth block to hierarchical structure, which can expose more active sites, at the same time, shorten the transmission distance of charge from the bulk to the surface, and reduce the loss of recombination in the transmission process.

[0055] Figure 2 The TEM, STEM-EDS of 10% Ni(OH)2-H2O2 / ZIS. As can be seen from the TEM of Figure 2 The TEM of the composite catalyst sample is in the form of irregular block agglomerates, and the element mapping shows that Zn, In, S, Ni and O coexist, Ni and O elements are mainly distributed in the edge and local area of the sample, and there is partial overlap with the distribution of Zn / In / S, indicating that Ni and O are loaded on the surface of ZnIn2S4 in the form of nanoparticles or thin layers, forming a heterojunction composite material.

[0056] Figure 3 The XRD of each monomer and the material prepared in each example. The crystal form and structure of the raw material and the Ni(OH)2-H2O2 / ZnIn2S4 sample with different mass ratios were characterized by XRD diffractometer. The diffraction peaks corresponding to the corresponding PDF card all appeared in the corresponding position, and there were no impurity peaks in the diffraction patterns of the samples with different proportions, which proved that no phase change occurred, indicating that the composite material Ni(OH)2-H2O2 / ZnIn2S4 was successfully synthesized.

[0057] Experimental Example 2

[0058] Preparation of membrane electrode: 5mg sample was dispersed in 300μL anhydrous ethanol, 600μL deionized water and 100μL Nafion mixed system, then the uniformly mixed slurry was drop-coated on fluorine-doped tin oxide (FTO) glass, and dried at room temperature. After drying, it was ready for use.

[0059] The membrane electrode was detected on the electrochemical workstation for photoelectrochemical and electrochemical measurement. In the standard three-electrode system, Pt electrode, saturated Ag / AgCl electrode and fluorine-doped tin oxide (FTO) glass with deposited sample film were used as the counter electrode, reference electrode and working electrode respectively. 0.2M Na2SO4 aqueous solution was used as the electrolyte. A 300W xenon lamp was used as the light source for transient photocurrent response. The electrochemical impedance spectrum (EIS) of the sample was tested in 0.2M Na2SO4 aqueous solution. The amplitude of electrochemical impedance spectrum was 10mV in the frequency range of 100khz-0.1hz.

[0060] Figure 4 photocurrent response curves of each monomer and each example preparation material, Figure 5 The electrochemical impedance spectroscopy of each monomer and each example preparation material, the photocatalytic charge separation and transport performance of the surface Ni(OH)2-H2O2 modified ZnIn2S4(ZIS) composite material is significantly better than that of the pure component and the low / high loading amount sample. The photocurrent results show that, with the increase of the Ni(OH)2-H2O2 loading amount from 1% to 10%, the photocurrent density increases from 4 μAcm -2 to a maximum of 7.5 μAcm -2 , and the further increase of the loading amount (15%, 20%) leads to the decrease of the current due to agglomeration; the impedance diagram synchronously confirms that the charge transfer resistance is the smallest when the loading amount is 10%, which is significantly lower than that of the pure ZIS. This is due to the optimization of the performance of the Ni-based cocatalyst by the H2O2 treatment through the generation of Ni 3+ , the introduction of structural defects and the improvement of the conductivity, and the appropriate loading amount of 10% can not only provide sufficient hydrogen evolution active sites, but also avoid the coverage of the ZIS surface by agglomeration, which provides a material design basis for efficient photocatalytic hydrogen production.

[0061] Example 3

[0062] Figure 6 photoluminescence spectra of each monomer and each example preparation material, Figure 7 ultraviolet-visible absorption spectra of each monomer and each example preparation material, which collectively reveal the influence of Ni(OH)2-H2O2 modification on the light absorption and charge separation performance of ZnIn2S4(ZIS). The PL spectrum shows that the light emission peak intensity of the pure ZIS is the highest, and the PL intensity of the 10% Ni(OH)2-H2O2 / ZIS composite material is significantly reduced, indicating that the H2O2 treated Ni(OH)2 as a cocatalyst can effectively inhibit the photoelectron-hole recombination of ZIS; in the ultraviolet-visible absorption spectrum, the absorption of each composite material in the visible light region (400-600 nm) is close to that of the pure ZIS, and the 10% loading amount sample does not appear obvious absorption weakening, indicating that the introduction of the Ni-based component does not sacrifice the visible light capture ability of ZIS. In summary, the 10% Ni(OH)2-H2O2 / ZIS provides a basis for efficient photocatalysis through the synergistic effect of “inhibiting charge recombination + maintaining light absorption”.

[0063] Figure 8The surface charge properties of ZnIn2S4(ZIS), Ni(OH)2and H2O2-treated Ni(OH)2(Ni(OH)2-H2O2) were displayed. The H2O2 treatment changed the surface charge of Ni(OH)2from negative to positive, which was speculated to be caused by selective adsorption or oxidation leading to surface charge reversal; there was an electrostatic attraction between the strong negative charge of ZIS and the positive charge of Ni(OH)2-H2O2, which was beneficial to the formation of a tight interface when the two were compounded, and promoted the transfer of photo-generated electrons from ZIS to the Ni-based cocatalyst, which was consistent with the results of the previous composite charge separation efficiency improvement.

[0064] Example 4

[0065] The photocatalytic hydrogen production experiments were carried out on the photocatalytic activity evaluation system of Beijing Zhongjiao Jinli Technology Co., Ltd. A 300W xenon lamp (PLS-SEX300C) was selected as the light source. The photocatalyst (20mg) and 1wt% Pt were suspended in a mixed solution of 0.1M Na2S and 0.1M Na2SO3. Before testing, the dissolved oxygen and air were removed by vacuumizing the light reaction system. During the photocatalytic reaction process, the temperature of the reaction solution was maintained at 8°C. The hydrogen production was analyzed by a gas chromatograph (GC-7920) through a molecular sieve column. The gas composition was analyzed by a molecular sieve column. The gas chromatograph was equipped with a thermal conductivity detector (TCD), and the carrier gas was high-purity argon (99.999%). The hydrogen production was calculated according to the retention time and peak area calibrated with standard hydrogen.

[0066] Figure 9 The photocatalytic hydrogen production-time curve, Figure 10 The hydrogen production rate column chart. It can be seen that pure Ni(OH)2has almost no hydrogen production activity, the hydrogen production of pure ZIS is low, and the hydrogen production of the composite material of H2O2-treated Ni(OH)2(Ni(OH)2-H2O2) and ZIS is significantly improved, and gradually increases with the increase of the loading amount of Ni(OH)2-H2O2from 1% to 10%, and the hydrogen production in 4h is the highest when the loading amount is 10%, and decreases slightly when the loading amount continues to increase (15%, 20%); the hydrogen production rate column chart further confirms that the hydrogen production rate of 10% Ni(OH)2-H2O2 / ZIS is 787μmol·g -1 ·h -1 , and the cumulative hydrogen production in four hours is ≥3150μmol·g -1 , which is significantly higher than that of pure ZIS (522μmol·g -1 ·h -1 ) and 10% Ni(OH)2 / ZIS (281μmol·g -1 ·h -1). The results show that H2O2-treated Ni(OH)2 as cocatalyst can form a high-efficiency synergistic effect with ZIS by optimizing the interface charge transfer and active site exposure, and 10% is the best loading ratio to achieve the highest hydrogen production performance.

[0067] The above only describes the preferred embodiments of the present application, and it should be pointed out that for ordinary skilled in the art, without departing from the principles of the present application, can make several improvements and refinements, these improvements and refinements should also be considered as the protection scope of the present application.

Claims

1. A hydrogen peroxide-modified nickel hydroxide composite indium sulfide zinc material, characterized in that, The nickel hydroxide composite indium sulfide zinc material is composed of hydrogen peroxide-modified nickel hydroxide and indium sulfide zinc.

2. The nickel hydroxide composite indium sulfide zinc material according to claim 1, characterized in that, The mass ratio of the hydrogen peroxide-modified nickel hydroxide to zinc indium sulfide is (1-20):

100.

3. The nickel hydroxide composite indium sulfide zinc material according to claim 1, characterized in that, The preparation method of the hydrogen peroxide-modified nickel hydroxide is as follows: Mix Ni(OH)2 and NaOH solutions, then add hydrogen peroxide solution dropwise, stir at room temperature, centrifuge to collect the precipitate, wash with ultrapure water, and vacuum dry.

4. The nickel hydroxide composite indium sulfide zinc material according to claim 3, characterized in that, The mass-to-volume ratio of Ni(OH)2, NaOH solution, and hydrogen peroxide solution is 0.2g:10mL:0.2ml.

5. The nickel hydroxide composite indium sulfide zinc material according to claim 4, characterized in that, The concentration of the NaOH solution is 0.1 mol / L; the concentration of the hydrogen peroxide solution is 30% hydrogen peroxide solution.

6. The nickel hydroxide composite indium sulfide zinc material according to claim 3, characterized in that, Stirring at room temperature for 1 hour.

7. The preparation method of the nickel hydroxide composite indium sulfide zinc material according to claim 1, characterized in that, Includes the following steps: Hydrogen peroxide-modified nickel hydroxide, zinc indium sulfide, and deionized water were mixed and electrostatically self-assembled, and then centrifuged and dried to obtain hydrogen peroxide-modified nickel hydroxide composite zinc indium sulfide material.

8. The preparation method according to claim 7, characterized in that, The method for preparing the zinc indium sulfide is as follows: Zinc acetate dihydrate, indium chloride tetrahydrate, thioacetamide, and ultrapure water were mixed and stirred for 0.5 hours, then placed in a hydrothermal reactor and reacted at 180°C for 12 hours. After centrifugation, washing, and drying, zinc indium thiosulfate was obtained.

9. The preparation method according to claim 8, characterized in that, The molar ratio of zinc acetate dihydrate, indium chloride tetrahydrate, and thioacetamide is 0.5:1:

8.

10. The application of the nickel hydroxide composite indium sulfide zinc material according to any one of claims 1-6 or the nickel hydroxide composite indium sulfide zinc material prepared by the preparation method according to any one of claims 7-8 in photocatalytic high-efficiency hydrogen production.

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