Nickel-based cocatalyst-loaded indium sulfide and preparation method and application thereof

Abstract

The invention belongs to the technical field of photocatalyst preparation, and particularly relates to indium sulfide loaded with a nickel-based cocatalyst and a preparation method and application thereof. The preparation method comprises the following steps: sequentially adding In (NO3) 3 * xH2O and thioacetamide into ultrapure water, stirring until the In (NO3) 3 * xH2O and thioacetamide are completely dissolved, and performing hydrothermal reaction on the obtained solution at a certain temperature to obtain In2S3. Then dispersing In2S3 in ultrapure water, adding a hole trapping agent, a proper amount of Ni source and the like, and depositing the promoter on the surface of In2S3 through a photodeposition method, so as to obtain the In2S3 catalyst loaded with different Ni-based promoters. According to the preparation method, the In2S3 catalyst loaded with different types of Ni bases as the cocatalysts is prepared through simple hydrothermal synthesis and photodeposition, in the photocatalysis process, photon-generated carriers can be captured by the cocatalysts, then oxidation-reduction reaction is carried out on the surfaces of the cocatalysts to produce H2O2, and high recombination with holes h < + > is avoided.

Description

Technical Field

[0001] The present invention belongs to the technical field of photocatalyst preparation, and in particular relates to indium sulfide loaded with a nickel-based co-catalyst, and a preparation method and application thereof. Background Art

[0002] Currently, the anthraquinone (AQ) process is the primary method for large-scale H2O2 production in industry. However, this method has numerous drawbacks, including severe environmental pollution, significant energy consumption, and high operational risks. Compared to the AQ process, photocatalytic H2O2 production requires only water, oxygen, and sunlight, making it more convenient and environmentally friendly, making it an ideal approach for future industrial H2O2 production.

[0003] Metal sulfides are commonly used photocatalysts with narrow band gaps, excellent charge separation, strong photoreduction performance and low redox energy. Unfortunately, when considering the light absorption range, photocatalysts with narrow band gaps should be selected, but this choice is often at the expense of redox capacity. Studies have gradually revealed that single metal sulfide photocatalysts have some shortcomings. They are usually limited by the intensity of absorbed light and rapid electron-hole recombination, resulting in low photocatalytic yield. For example, the main defect of indium sulfide (In2S3) as a commonly used photocatalyst is the rapid recombination of photogenerated electrons and holes, which leads to its low efficiency in photocatalytic production of H2O2. Therefore, how to improve the charge separation efficiency of In2S3 through a series of modification strategies is of great significance for the development of high-performance H2O2 production photocatalysts. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to address the shortcomings of the existing technology and provide a method that effectively introduces a co-catalyst through a simple photodeposition method to promote the separation of photogenerated electrons and holes in indium sulfide (In2S3). Therefore, the electron transmission rate is improved, and the catalyst production rate of H2O2 is increased, so that it can efficiently generate hydrogen peroxide in ultrapure water under visible light irradiation, and has good application prospects.

[0005] In order to solve the above technical problems, the present invention discloses a method for preparing indium sulfide loaded with a nickel-based co-catalyst, comprising the following steps:

[0006] S1. Indium sulfide was dispersed in ultrapure water, followed by the addition of triethylamine alcohol, a nickel salt solution and an inorganic oxyacid sodium salt solution to obtain a mixed solution;

[0007] S2. The mixed solution is irradiated with a xenon lamp under continuous stirring to react. After the reaction is completed, the mixed solution is centrifuged, washed, and dried to obtain indium sulfide loaded with a nickel-based co-catalyst.

[0008] The concentration of indium sulfide in the mixed solution is 2-4 mg / mL; preferably, the concentration of indium sulfide in the mixed solution is 2.86 mg / mL.

[0009] The volume ratio of the ultrapure water, triethylamine alcohol, nickel salt solution and inorganic oxygen-containing acid sodium salt solution is (10-30):3:2:(0-20).

[0010] The concentration of the nickel salt solution is 0.01 to 0.03 M, preferably, the concentration of the nickel salt solution is 0.02 M; the concentration of the inorganic oxyacid sodium salt solution is 0.01 to 0.03 M, preferably, the concentration of the inorganic oxyacid sodium salt solution is 0.02 M.

[0011] Wherein, the nickel salt is nickel chloride.

[0012] Wherein, the inorganic oxyacid sodium salt is sodium selenite and / or sodium phosphite;

[0013] Preferably, the inorganic oxyacid sodium salt is sodium selenite and sodium phosphite.

[0014] Among them, in S2, the specific conditions for the reaction are: a xenon lamp light source wavelength greater than 420nm, a distance of 25cm from the mixed solution, and irradiation for 35min.

[0015] Wherein, in S2, the centrifugation is carried out under the following conditions: centrifugation at 7500 rpm for 4 min; and the drying is carried out under vacuum at 60° C. for 12 h.

[0016] Furthermore, the indium sulfide loaded with nickel-based co-catalyst prepared by the above preparation method is also within the protection scope of the present invention;

[0017] Furthermore, the use of indium sulfide loaded with nickel-based co-catalyst prepared by the above preparation method in the preparation of H2O2 by photocatalytic reaction is also within the scope of protection of the present invention;

[0018] Furthermore, the concentration of the indium sulfide loaded with nickel-based co-catalyst in the reaction system is 20% to 50%, preferably 20%.

[0019] Specifically, in some embodiments of the present invention, the above-mentioned preparation method was used to successfully synthesize In2S3 loaded with Ni as a co-catalyst, In2S3 loaded with NiSe as a co-catalyst, In2S3 loaded with NiP2 as a co-catalyst, and In2S3 loaded with both NiSe and NiP2 as co-catalysts. By testing the above-mentioned four catalysts for the photocatalytic production of H2O2 from O2 and H2O, it was demonstrated that the indium sulfide photocatalyst loaded with nickel-based co-catalyst prepared by the present invention can efficiently generate H2O2 in pure water compared to conventional pure In2S3 catalysts, and has good application prospects.

[0020] Beneficial effects:

[0021] This preparation method prepares In2S3 catalysts loaded with different types of Ni-based co-catalysts through simple hydrothermal synthesis and photodeposition. During the photocatalytic process, the photogenerated carriers can be captured by the co-catalyst and then undergo redox reactions on the co-catalyst surface to produce H2O2, avoiding the reaction with holes h + By introducing a co-catalyst to promote the separation of photogenerated electrons and holes in In2S3, the electron transmission rate is increased, and the catalyst's H2O2 production rate is increased, enabling In2S3 to efficiently generate hydrogen peroxide in ultrapure water under visible light irradiation, showing good application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments, and the above and / or other advantages of the present invention will become more apparent.

[0023] Figure 1 The X-ray diffraction (XRD) patterns of the photocatalysts prepared in Examples 1 to 4 of the present invention and the control group are shown.

[0024] Figure 2 The scanning electron microscope energy spectrum (EDS) images of the photocatalysts prepared in Examples 1 to 4 of the present invention and the control group are shown.

[0025] Figure 3 This is a graph showing the increase in H2O2 production over time for the photocatalysts prepared in Examples 1 to 4 of the present invention and the control group.

[0026] Figure 4 This is a graph showing the production of H2O2 within 1 hour by the photocatalysts prepared in Examples 1 to 4 of the present invention and the control group. DETAILED DESCRIPTION

[0027] The experimental methods described in the following examples are conventional methods unless otherwise specified; the reagents and materials are commercially available unless otherwise specified.

[0028] The indium sulfide (In2S3) used in the following examples was prepared in the laboratory. The specific preparation method was as follows: 2 mmol In(NO3)3·xH2O and 4 mmol thioacetamide were mixed and added to 60 mL of ultrapure water, stirred until completely dissolved, and then hydrothermally reacted at 180°C for 12 hours. After the reaction was completed, it was cooled to room temperature, and then centrifuged and washed with water and ethanol three times, and finally vacuum dried at 60°C for 12 hours to obtain In2S3.

[0029] Example 1:

[0030] 100 mg of In2S3 sample was dispersed in 30 mL of ultrapure water, 3 mL of triethanolamine was added and the mixture was mixed and stirred, 2 mL of NiCl2 solution (0.02 M) was added, and then a xenon lamp (λ>420 nm) was used to irradiate the mixed solution at a distance of 25 cm for 35 minutes under continuous stirring; the product was then centrifuged at 7500 rpm for 4 minutes, washed twice with water, and finally vacuum dried at 60°C for 12 hours to obtain an In2S3 sample loaded with Ni as a co-catalyst, which was recorded as Ni / In2S3 after grinding.

[0031] Example 2:

[0032] 100 mg of In2S3 sample was dispersed in 20 mL of ultrapure water, 3 mL of triethanolamine was added and the mixture was mixed and stirred, 2 mL of NiCl2 solution (0.02 M) and 10 mL of Na2SeO3 solution (0.02 M) were added, and then irradiated with a xenon lamp (λ>420 nm) at a distance of 25 cm from the mixed solution for 35 min under continuous stirring; the product was then centrifuged at 7500 rpm for 4 min, washed twice with water, and finally vacuum dried at 60°C for 12 h to obtain an In2S3 sample loaded with NiSe co-catalyst, which was recorded as NiSe / In2S3 after grinding.

[0033] Example 3:

[0034] 100 mg of In2S3 sample was dispersed in 20 mL of ultrapure water, 3 mL of triethanolamine was added and the mixture was mixed and stirred, 2 mL of NiCl2 solution (0.02 M) and 10 mL of Na2H2PO2 solution (0.02 M) were added, and then irradiated with a xenon lamp (λ>420 nm) at a distance of 25 cm from the mixed solution for 35 minutes under continuous stirring; the product was then centrifuged at 7500 rpm for 4 minutes, washed twice with water, and finally dried in vacuum at 60°C for 12 hours to obtain an In2S3 sample loaded with NiP2 co-catalyst, which was recorded as NiP2 / In2S3 after grinding.

[0035] Example 4:

[0036] 100 mg of In2S3 sample was dispersed in 10 mL of ultrapure water, 3 mL of triethanolamine was added and mixed, and 2 mL of NiCl2 solution (0.02 M), 10 mL of Na2H2PO2 solution (0.02 M) and 10 mL of Na2SeO3 solution (0.02 M) were added in sequence. Then, a xenon lamp (λ>420 nm) was used to irradiate the mixed solution at a distance of 25 cm for 35 min under continuous stirring; the product was then centrifuged at 7500 rpm for 4 min, washed twice with water, and finally dried in vacuum at 60 ° C for 12 h to obtain an In2S3 sample loaded with NiSe / NiP2 co-catalyst, which was recorded as NiSe / In2S3 / NiP2 after grinding.

[0037] Example 5:

[0038] The catalysts and pure In2S3 prepared in Examples 1 to 4 were characterized by X-ray diffraction (XRD). Figure 1 The XRD patterns of the photocatalysts and pure In2S3 prepared in Examples 1 to 4 are shown in Table 1. Figure 1 It can be seen that the In2S3 sample prepared by the hydrothermal method has six distinct characteristic peaks at 2θ of 14.3°, 23.3°, 27.4°, 33.2°, 43.6°, and 47.7°, corresponding to its (103), (116), (109), (0012), (1015), and (2212) crystal planes, respectively, which are consistent with the standard spectrum of β-In2S3 (PDF#25-0390). After the photodeposition of the co-catalyst, the XRD peak patterns of Examples 1 to 4 did not change, indicating that the loading of the co-catalyst on the In2S3 surface did not destroy the crystal structure of In2S3. In addition, due to the low loading of the Ni-based co-catalyst, no characteristic peaks of Ni were observed in the XRD patterns of the composite materials.

[0039] The element types of the catalysts and pure In2S3 prepared in Examples 1 to 4 were analyzed by scanning electron microscopy (EDS). Figure 2 In the figure, a, b, c, d and e are element types of In2S3, Ni / In2S3, NiP2 / In2S3, NiSe / In2S3 and NiSe / In2S3 / NiP2 respectively. Figure 2 It can be seen that the In2S3 without co-catalyst loading only contains two elements, In and S. After loading various Ni-based co-catalysts, the element types of Examples 1 to 4 are consistent with the co-catalyst types. Taking NiSe / In2S3 / NiP2 as an example, Figure 2 In, S, Ni, Se and P elements were detected simultaneously in the e, indicating the successful loading of NiSe and NiP2. Figure 2 Figure f is the quantitative analysis diagram of NiSe / In2S3 / NiP2 elements. The three elements Ni, P, and Se are highly dispersed on the catalyst surface, and the catalyst deposition effect is good.

[0040] The catalysts prepared in Examples 1 to 4 were tested for photocatalytic production of H2O2 from O2 and H2O. Pure In2S3 without any nickel-based co-catalyst was used as a control group. The specific experimental steps were as follows: 10 mg of the catalyst was dispersed in a 100 mL three-necked flask containing 50 mL of deionized water and stirred in the dark with oxygen for 30 minutes to achieve O2 adsorption-desorption equilibrium. A 300W xenon lamp (PLS-SXE300 / 300UV, Perfect Light) was used to simulate sunlight (420 nm cutoff) and irradiate the reaction flask for 1 hour. The xenon lamp was 28 cm away from the reactor. During the reaction, 1.1 mL was sampled after 1 hour and filtered with a 0.22 μm organic filter head to remove the catalyst solid. 1 mL of the reaction solution obtained after filtration was taken, and 1 mL of 0.4 M KI solution and 1 mL of 0.1 M potassium hydrogen phthalate solution were added respectively. After mixing, the mixture was color-developed in the dark for 1 hour (H2O2 + 3I - +2H + →I3 - +2H2O), and after color development, the absorbance of the solution at 350nm was measured with an ultraviolet spectrophotometer, and the H2O2 production was calculated using the fitted absorbance-H2O2 concentration standard curve.

[0041] Figure 3 The graph of the photocatalysts prepared in Examples 1 to 4 and the control group showing the increase in H2O2 production over time is shown in FIG. Figure 4 The graph shows the production of H2O2 produced by the photocatalysts prepared in Examples 1 to 4 and the control group within 1 hour. Figure 3 and Figure 4 It can be seen that under the same dosage, compared with the pure In2S3 catalyst in the control group, the photocatalytic production of H2O2 by the catalysts of Examples 1 to 4 is higher, and the photocatalytic production of H2O2 in 1 h can reach a maximum of 2659.58 μmol g -1 h -1 The amount of H2O2 produced by Ni / In2S3, NiSe / In2S3, NiP2 / In2S3 and NiSe / In2S3 / NiP2 catalysts was 22.21, 25.36, 27.59 and 32.67 times that of the control group In2S3, respectively. The increase in production is attributed to the promotion of e - -h + Separation of the two, promoting e - This also shows that the indium sulfide photocatalyst loaded with nickel-based co-catalyst prepared by the present invention can efficiently generate H2O2 in pure water and has good application prospects.

[0042] The present invention provides a nickel-based co-catalyst-supported indium sulfide, a preparation method, and a method for its application. While there are numerous methods and approaches for implementing this technical solution, the foregoing description is merely a preferred embodiment of the present invention. It should be noted that those skilled in the art may make various improvements and modifications without departing from the principles of the present invention, and such improvements and modifications are also within the scope of protection of the present invention. Any components not specified in this embodiment may be implemented using existing technologies.

Claims

1. A method for preparing indium sulfide loaded with a nickel-based co-catalyst, characterized in that: The steps include: S1. Indium sulfide was dispersed in ultrapure water, followed by the addition of triethylamine alcohol, a nickel salt solution and an inorganic oxyacid sodium salt solution to obtain a mixed solution; S2. The mixed solution is irradiated with a xenon lamp under continuous stirring to react. After the reaction is completed, the mixed solution is centrifuged, washed, and dried to obtain indium sulfide loaded with a nickel-based co-catalyst.

2. The preparation method according to claim 1, characterized in that The concentration of the indium sulfide in the mixed solution is 2-4 mg / mL.

3. The preparation method according to claim 1, characterized in that The volume ratio of the ultrapure water, triethylamine alcohol, nickel salt solution and inorganic oxygen-containing acid sodium salt solution is (10-30):3:2:(0-20).

4. The preparation method according to claim 3, characterized in that The concentration of the nickel salt solution is 0.01-0.03M; the concentration of the inorganic oxygen-containing acid sodium salt solution is 0.01-0.03M.

5. The preparation method according to claim 4, characterized in that The nickel salt is nickel chloride.

6. The preparation method according to claim 4, characterized in that The inorganic oxyacid sodium salt is sodium selenite and / or sodium phosphite.

7. The preparation method according to claim 1, characterized in that In S2, the reaction is carried out under the following specific conditions: a xenon lamp light source with a wavelength greater than 420 nm, a distance of 25 cm from the mixed solution, and irradiation for 35 minutes.

8. Indium sulfide loaded with a nickel-based co-catalyst prepared by the preparation method according to any one of claims 1 to 7.

9. Use of the indium sulfide loaded with a nickel-based co-catalyst according to claim 8 in the preparation of H2O2 by photocatalytic reaction.

10. The use according to claim 9, characterized in that The concentration of the indium sulfide loaded with nickel-based co-catalyst in the reaction system is 20% to 50%.

Images