Composite catalyst, preparation and use thereof

Abstract

A composite catalyst and its preparation and application. The present application provides a preparation method of a composite photocatalyst of cobalt oxime supported graphite phase carbon nitride and indium zinc sulfide and its application. The catalyst is composed of Co III (dmgH)2(4-(Me2N)py)Cl, g-C3N4 and ZnIn2S4; the g-C3N4 accounts for 2.0% Wt of the ZnIn2S4; the Co III (dmgH)2(4-(Me2N)py)Cl accounts for 2.5% Wt of the g-C3N4 / ZnIn2S4. The Co III (dmgH)2(4-(Me2N)py)Cl supported g-C3N4 / ZnIn2S4 composite photocatalyst provided by the present application has a significantly improved photocatalytic performance compared with the Co III (dmgH)2(4-(Me2N)py)Cl and the ZnIn2S4 photocatalyst supported by the g-C3N4 alone.

Description

Technical Field

[0001] This invention relates to a Co III Preparation of (dmgH)2(4-(Me2N)py)Cl / g-C3N4 / ZnIn2S4 composite catalyst and its application in photocatalytic hydrogen production. Background Technology

[0002] Clean energy includes renewable energy sources such as solar, wind, and hydropower. Its characteristic is that it emits almost no harmful gases during production, reducing negative environmental impacts. The demand for sustainable development, environmental protection, and efficient new energy sources is becoming increasingly urgent. Hydrogen energy, with its high calorific value and water as a combustion product, is highly favored. Photocatalytic hydrogen production technology is an environmentally friendly technology that uses solar energy to decompose water into hydrogen and oxygen. With the increasing global demand for clean energy, photocatalytic hydrogen production has become a research area of ​​great interest. This technology stems from the pursuit of improvements to traditional hydrogen production methods, aiming to reduce environmental impact and energy costs.

[0003] In the research on photocatalytic water splitting for hydrogen production, it has been found that single photocatalysts suffer from a series of drawbacks, including low absorbance, poor stability, and easy recombination of electrons and holes. Therefore, forming heterojunctions and supporting suitable co-catalysts can effectively solve this problem. While traditional noble metal hydrogen production co-catalysts can effectively suppress electron-hole recombination and improve photocatalytic performance, their high cost limits their industrial application. Therefore, developing inexpensive, high-activity non-noble metal co-catalysts is of paramount importance. Summary of the Invention

[0004] The purpose of this invention is to prepare a g-C3N4 / ZnIn2S4 composite catalyst and to incorporate Co... III (dmgH)2(4-(Me2N)py)Cl was used as a co-catalyst and supported on g-C3N4 / ZnIn2S4 to obtain a Co catalyst with a large specific surface area and many catalytic sites. III (dmgH)2(4-(Me2N)py)Cl / g-C3N4 / ZnIn2S4 composite photocatalyst, and applied it to the field of photocatalytic water splitting for hydrogen production.

[0005] The technical solution of this invention:

[0006] To achieve the above objectives, the present invention adopts the following technical solution: A composite catalyst, which is Co III (dmgH)2(4-(Me2N)py)Cl / g-C3N4 / ZnIn2S4, this catalyst is composed of Co III It is composed of (dmgH)2(4-(Me2N)py)Cl, g-C3N4 and ZnIn2S4; Co III The mass ratio (wt%) of (dmgH)2(4-(Me2N)py)Cl and g-C3N4 / ZnIn2S4 is 2.0% to 3.0% (preferably 2.4% to 2.6%). The mass ratio (Wt%) of g-C3N4 and ZnIn2S4 is 1.5% to 2.5% (preferably 1.9% to 2.1%). Co III (dmgH)2(4-(Me2N)py)Cl was loaded onto g-C3N4 / ZnIn2S4; g-C3N4 / ZnIn2S4 is a complex formed by adding g-C3N4 during the synthesis of ZnIn2S4. (1) Co was obtained by organic synthesis, heating and oxidation using cobalt chloride, dimethylglyoxime and 4-dimethylaminopyridine as raw materials. III (dmgH)2(4-(Me2N)py)Cl; (2) g-C3N4 was prepared from melamine; (3) g-C3N4 / ZnIn2S4 was prepared from g-C3N4, zinc chloride, indium chloride tetrahydrate, and thioacetamide by hydrothermal method, wherein the mass ratio (wt%) of g-C3N4 to ZnIn2S4 was 1.5% to 2.5% (preferably 1.8% to 2.2%); (4) g-C3N4 / ZnIn2S4 was obtained by impregnation method. Co III (dmgH)2(4-(Me2N)py)Cl / g-C3N4 / ZnIn2S4,Co III The mass ratio (wt%) of (dmgH)2(4-(Me2N)py)Cl and g-C3N4 / ZnIn2S4 is 2.0% to 3.0% (preferably 2.4% to 2.6%). Step (1) Co III The specific preparation process of (dmgH)2(4-(Me2N)py)Cl is as follows: The container is evacuated and N2 / O2 with a volume ratio of 95-99:1-5 (preferably 98-99:1-2) is introduced repeatedly 2-4 times. Then, 100 mL of 93%-98% (95%-96%) ethanol solution is added; 2.4 g-2.8 g (preferably 2.5 g-2.7 g) of cobalt chloride hexahydrate and 2.6 g-2.9 g (preferably...) are added. Select 2.7g-2.8g of dimethylglyoxime, heat the solution to 68℃-75℃ (preferably 69℃-72℃), then add 1.3g-1.4g (preferably 1.31g-1.32g) of 4-dimethylaminopyridine, and cool the resulting solution to room temperature; then purge the solution with air for 30min-60min (preferably 40min-50min) to produce a precipitate; filter the obtained solid product, wash, and dry to obtain Co. III (dmgH)2(4-(Me2N)py)Cl. The specific preparation process of g-C3N4 in step (2) is as follows: using 5g to 10g (preferably 6g to 9g) of melamine as a precursor, heating at a heating rate of 2℃ / min to 3℃ / min (preferably 2.3℃ / min to 2.5℃ / min) to 540℃ to 570℃ (preferably 550℃ to 560℃) for 2h to 5h (preferably 3h to 4h), and then grinding to obtain g-C3N4 powder. The specific preparation process of g-C3N4 / ZnIn2S4 in step (3) is as follows: control the mass ratio (Wt%) of g-C3N4 and ZnIn2S4 to be 2.0% to 3.0% (preferably 2.3% to 2.6%), take 0.01g to 0.03g (preferably 0.01g to 0.02g) of g-C3N4 and dissolve it in 50mL to 70mL (preferably 55mL to 65mL) of deionized water, and add 0.13g to 0.16g (preferably 0.14g to 0.16g) of g-C3N4. Add ZnCl2, 0.65g-0.70g (preferably 0.67g-0.69g) InCl3·4H2O, and 0.60g-0.70g (preferably 0.61g-0.65g) thioacetamide to the solution and stir until homogeneous. Transfer the solution to a hydrothermal reactor and react at 170℃-190℃ (preferably 178℃-182℃) for 10h-15h (preferably 11h-13h). After washing, drying, and grinding the precipitate, g-C3N4 / ZnIn2S4 powder is obtained. Step (4) Co III The specific preparation process of (dmgH)2(4-(Me2N)py)Cl / g-C3N4 / ZnIn2S4 is as follows: Based on Co III The mass ratio (wt%) of (dmgH)2(4-(Me2N)py)Cl and g-C3N4 / ZnIn2S4 is 2.0%–3.0% (preferably 2.3%–2.6%), and Co is added. III (dmgH)2(4-(Me2N)py)Cl and g-C3N4 / ZnIn2S4 were dissolved in ethanol and sonicated for 2-6 hours (preferably 3-5 hours), and then the mixture containing Co was added... III A solution of (dmgH)2(4-(Me2N)py)Cl was added to a solution containing g-C3N4 / ZnIn2S4. The solution was stirred, evaporated to dryness, and then ground to obtain Co. III (dmgH)2(4-(Me2N)py)Cl / g-C3N4 / ZnIn2S4 composite catalyst. Co III The preparation method of (dmgH)2(4-(Me2N)py)Cl / g-C3N4 / ZnIn2S4 catalyst, with specific steps as follows: (1) Preparation of Co IIIThe specific process for (dmgH)2(4-(Me2N)py)Cl is as follows: A three-necked flask is evacuated and N2 / O2 (volume ratio 98-99:1-2) is repeatedly introduced three times. 100 mL of 95% ethanol solution is added; 2.5 g of cobalt chloride hexahydrate and 2.75 g of dimethylglyoxime are added. The solution is heated to 70°C, and immediately 1.315 g of 4-dimethylaminopyridine is added. The resulting solution is cooled to room temperature. Air is then passed through the solution for 60 min to produce a precipitate. The obtained solid product is filtered, washed, and dried to obtain Co. III (dmgH)2(4-(Me2N)py)Cl; (2) The specific process for preparing g-C3N4 is as follows: 10g of melamine is used as a precursor, placed in a 50mL crucible and heated to 550℃ in a muffle furnace at a heating rate of 2.3℃ / min for 3h, cooled to room temperature, and ground to obtain g-C3N4 powder. (3) The specific process for preparing g-C3N4 / ZnIn2S4 is as follows: The g-C3N4 obtained in (1) is transferred to the lining of a 100mL hydrothermal reactor according to the mass ratio (Wt%) of g-C3N4 / ZnIn2S4 as 0.5%, 1.0%, 2.0%, 3.0%, and 5.0% (optimal 2.0%). 0.14g ZnCl2, 0.69g InCl3·4H2O, and 0.60g thioacetamide are added to a 60mL aqueous solution and stirred evenly. The solution is then transferred to the hydrothermal reactor and reacted at 180℃ for 12h in a forced-air drying oven. After precipitate washing, drying, and grinding, g-C3N4 / ZnIn2S4 powder is obtained. (4) Preparation of Co III The specific process for (dmgH)2(4-(Me2N)py)Cl / g-C3N4 / ZnIn2S4 is as follows: Based on the Co obtained in (3) III (dmgH)2(4-(Me2N)py)Cl according to Co III The mass ratio (wt%) of (dmgH)2(4-(Me2N)py)Cl / g-C3N4 / ZnIn2S4 is 0.1%, 0.5%, 1.0%, 2.5%, and 5.0% (preferably 2.5%), dissolved in 60 mL of ethanol solution containing g-C3N4 / ZnIn2S4, ultrasonically dispersed, and the solution was stirred, evaporated to dryness, and ground to obtain Co. III (dmgH)2(4-(Me2N)py)Cl / g-C3N4 / ZnIn2S4 powder. The composite catalyst can be used as a catalyst in the photocatalytic water splitting process for hydrogen production. The photocatalytic hydrogen production performance of the LabSolor-H2 photocatalytic water splitting hydrogen production system of Pofilai Technology Co., Ltd. was tested. The test conditions were as follows: a 300W xenon lamp with a wavelength range of 420nm-800nm ​​was used as a simulated sunlight source, the xenon lamp operating current was 15mA, the illumination time was 1h, Ar gas was used as the carrier gas, and the hydrogen production was measured by gas chromatography equipped with a TDX-01 column and a TCD detector. The Co provided by this invention III (dmgH)2(4-(Me2N)py)Cl supported g-C3N4 / ZnIn2S4 composite photocatalyst compared to Co alone III The photocatalytic performance of ZnIn2S4 supported by (dmgH)2(4-(Me2N)py)Cl and g-C3N4 alone is significantly improved.

[0007] The significant advantages of this invention are: A heterojunction structure is formed using two semiconductors, g-C3N4 and ZnIn2S4, and a non-noble metal-organic compound Co. III (dmgH)₂(4-(Me₂N)py)Cl is used as a co-catalyst, and its preparation process is simple, mild, and relatively inexpensive. Its testing shows that Co… III The photocatalytic hydrogen production activity of (dmgH)2(4-(Me2N)py)Cl / g-C3N4 / ZnIn2S4 is 3.4 times that of ZnIn2S4 alone. Attached Figure Description

[0008] Figure 1 Photocatalytic hydrogen production activity relationship diagrams for Examples 1, 2, 3, 5, 7, and 8;

[0009] Figure 2 Photocatalytic hydrogen production activity relationship diagrams for Examples 5, 10, 11, 12, 14, and 16;

[0010] Figure 3 Photocatalytic hydrogen production activity diagrams for Examples 1, 5, 9, and 14;

[0011] Figure 4 XRD patterns of Examples 1, 5, 9, and 14 (ZnIn2S4, g-C3N4, g-C3N4 / ZnIn2S4, and Co can be inferred by comparison with standard PDF cards and literature, and by diffraction peak intensities). III Successful preparation of (dmgH)2(4-(Me2N)py)Cl / g-C3N4 / ZnIn2S4);

[0012] Figure 5 SEM image of Example 11 (Co can be observed) III(dmgH)2(4-(Me2N)py)Cl and g-C3N4 are loaded on the surface of ZnIn2S4. Detailed Implementation

[0013] The present invention will be further described in detail below through specific embodiments.

[0014] The Co used in the examples III (dmgH)2(4-(Me2N)py)Cl was prepared according to the following procedure: A three-necked flask was evacuated and purged with N2 / O2 (98:2 volume ratio) three times. 100 mL of 95% ethanol solution was added. 2.5 g of cobalt chloride hexahydrate and 2.75 g of dimethylglyoxime were added. The solution was heated to 70°C, and immediately 1.315 g of 4-dimethylaminopyridine was added. The resulting solution was cooled to room temperature. Air was then bubbled into the solution (at a rate of 15 mL / min) for 60 min to produce a precipitate. The obtained solid product was filtered, repeatedly washed with deionized water and anhydrous ethanol, and dried to obtain Co. III The successful preparation of the product was confirmed by infrared spectroscopy and nuclear magnetic resonance hydrogen spectroscopy analysis of the (dmgH)2(4-(Me2N)py)Cl catalyst. Furthermore, the successful preparation of the product was confirmed by comparison with the literature (reference [1] Kilic, A., Filat, H., Aytar, E. et al. Dicobaloxime / organodicobaloximes bridged by different axial groups: synthesis, characterization, spectroscopy, and catalysis. Chem. Pap. 71, 1705–1720 (2017).). Co III (dmgH)2(4-(Me2N)py)Cl.

[0015] The g-C3N4 used in the examples were all prepared according to the following process: 10g of melamine was weighed as a precursor, ground, and placed in a 50mL crucible in a muffle furnace and heated to 550℃ at a heating rate of 2.3℃ / min for 3h. After cooling to room temperature, the g-C3N4 catalyst was obtained by grinding. XRD test showed that g-C3N4 was successfully prepared.

[0016] ZnIn2S4 is prepared according to the following process, the steps of which are as follows: 0.14 g ZnCl2, 0.69 g InCl3·4H2O, and 0.60 g thioacetamide were weighed into 60 mL of deionized water and stirred until homogeneous. The solution was then transferred to a 100 mL hydrothermal reactor and reacted at 180 °C for 12 h in a forced-air drying oven. After washing, drying, and grinding, the ZnIn2S4 catalyst was obtained. XRD analysis confirmed that ZnIn2S4 was successfully prepared. The catalysts prepared in the following examples were tested for photocatalytic hydrogen production performance in the LabSolor-H2 photocatalytic water splitting hydrogen production system of Pofilai Technology Co., Ltd. Ar gas was used as the carrier gas, and the hydrogen production was measured by gas chromatography equipped with a TDX-01 column and a TCD detector. Photocatalytic water splitting to produce hydrogen: 0.1 g of catalyst was added to 100 mL of 10% (v / v) TEOA (… 三乙醇胺 The solution was used to simulate the sun's light source with a 300W xenon lamp (wavelength range of 420nm-800nm). The xenon lamp's operating current was 15mA, and the illumination time was 1h.

[0017] Example 1

[0018] (1) Preparation of g-C3N4 / ZnIn2S4 composite catalyst: Weigh 0.14g ZnCl2, 0.69g InCl3·4H2O and 0.60g thioacetamide and add them to 60mL of aqueous solution and stir vigorously until uniform. Transfer the suspension to 100mL hydrothermal reactor and react at 180℃ for 12h in a forced-air drying oven. After washing, drying and grinding the precipitate, ZnIn2S4 powder with a mass ratio of g-C3N4 to ZnIn2S4 of 0 (Wt%) was obtained. (2) Photocatalytic water splitting to produce hydrogen: 0.1g of photocatalyst was added to 100mL of 10% TEOA solution. A 300W xenon lamp (420nm-800nm) was used to simulate the sun's light source. The xenon lamp's operating current was 15mA and the illumination time was 1h. (3) In this reaction, the rate of hydrogen production from water by photocatalytic decomposition is 410 μmol / g / h (micromoles per gram per hour, the same below).

[0019] Example 2

[0020] (1) Preparation of g-C3N4 / ZnIn2S4 composite catalyst: Weigh 0.0025g g-C3N4 and add it to 60mL of aqueous solution. Disperse it evenly by ultrasonication. Weigh 0.14g ZnCl2, 0.69g InCl3·4H2O and 0.60g thioacetamide and add them to the aqueous solution containing g-C3N4. Stir evenly and transfer the suspension to a 100mL hydrothermal reactor. React at 180℃ for 12h in a forced-air drying oven. After precipitate washing, drying and grinding, g-C3N4 / ZnIn2S4 powder with a mass ratio of g-C3N4 to ZnIn2S4 of 0.5 (Wt%) is obtained. (2) Photocatalytic water splitting to produce hydrogen: 0.1g of composite photocatalyst was added to 100mL of 10% TEOA solution. A 300W xenon lamp (420nm-800nm) was used to simulate the sun's light source. The xenon lamp's working current was 15mA and the illumination time was 1h. (3) In this reaction, the photocatalytic water splitting hydrogen production rate was 610 μmol / g / h, which was 1.5 times higher than that of ZnIn2S4 alone (0.1g ZnIn2S4 was used as a control instead of photocatalyst, and the process and conditions were the same as in step 2 above, except that an equal mass of ZnIn2S4 was used instead of g-C3N4 / ZnIn2S4).

[0021] Example 3

[0022] The process and conditions are the same as in Example 2, except that the amount of g-C3N4 used in step (1) is 0.005g, and a g-C3N4 / ZnIn2S4 composite photocatalyst with a mass ratio of g-C3N4 to ZnIn2S4 of 1.0 (Wt%) is obtained.

[0023] In this reaction, the photocatalytic water splitting hydrogen production rate was 660 μmol / g / h, which was 1.6 times higher than that of ZnIn2S4 alone (0.1 g ZnIn2S4 was used as a control instead of the photocatalyst, and the process and conditions were the same as in step 2 above, except that an equal mass of ZnIn2S4 was used instead of g-C3N4 / ZnIn2S4).

[0024] Example 4

[0025] The process and conditions are the same as in Example 2, except that the amount of g-C3N4 used in step (1) is 0.0075g, and a g-C3N4 / ZnIn2S4 composite photocatalyst with a mass ratio of g-C3N4 to ZnIn2S4 of 1.5 (Wt%) is obtained.

[0026] In this reaction, the photocatalytic water splitting hydrogen production rate was 684 μmol / g / h, which was 1.67 times higher than that of ZnIn2S4 alone (0.1 g ZnIn2S4 was used as a control instead of the photocatalyst, and the process and conditions were the same as in step 2 above, except that an equal mass of ZnIn2S4 was used instead of g-C3N4 / ZnIn2S4).

[0027] Example 5

[0028] The process and conditions are the same as in Example 2, except that the amount of g-C3N4 used in step (1) is 0.01g, and a g-C3N4 / ZnIn2S4 composite photocatalyst with a mass ratio of g-C3N4 to ZnIn2S4 of 2.0 (Wt%) is obtained.

[0029] In this reaction, the photocatalytic water splitting hydrogen production rate was 745 μmol / g / h, which was 1.8 times higher than that of ZnIn2S4 alone (0.1 g ZnIn2S4 was used as a control instead of the photocatalyst, and the process and conditions were the same as in step 2 above, except that an equal mass of ZnIn2S4 was used instead of g-C3N4 / ZnIn2S4).

[0030] Example 6

[0031] The process and conditions are the same as in Example 2, except that the amount of g-C3N4 used in step (1) is 0.0125g, and a g-C3N4 / ZnIn2S4 composite photocatalyst with a mass ratio of g-C3N4 to ZnIn2S4 of 2.5 (Wt%) is obtained.

[0032] In this reaction, the photocatalytic water splitting hydrogen production rate was 700 μmol / g / h, which was 1.7 times higher than that of ZnIn2S4 alone (0.1 g ZnIn2S4 was used as a control instead of the photocatalyst, and the process and conditions were the same as in step 2 above, except that an equal mass of ZnIn2S4 was used instead of g-C3N4 / ZnIn2S4).

[0033] Example 7

[0034] The process and conditions are the same as in Example 2, except that the amount of g-C3N4 used in step (1) is 0.015g, and a g-C3N4 / ZnIn2S4 composite photocatalyst with a mass ratio of g-C3N4 to ZnIn2S4 of 3.0 (Wt%) is obtained.

[0035] In this reaction, the photocatalytic water splitting hydrogen production rate was 545 μmol / g / h, which was 1.3 times higher than that of ZnIn2S4 alone (0.1 g ZnIn2S4 was used as a control instead of the photocatalyst, and the process and conditions were the same as in step 2 above, except that an equal mass of ZnIn2S4 was used instead of g-C3N4 / ZnIn2S4).

[0036] Example 8

[0037] The process and conditions are the same as in Example 2, except that the amount of g-C3N4 used in step (1) is 0.025g, and a g-C3N4 / ZnIn2S4 composite photocatalyst with a mass ratio of g-C3N4 to ZnIn2S4 of 5.0 (Wt%) is obtained.

[0038] In this reaction, the photocatalytic water splitting hydrogen production rate was 435 μmol / g / h, which was 1.1 times higher than that of ZnIn2S4 alone (0.1 g ZnIn2S4 was used as a control instead of the photocatalyst, and the process and conditions were the same as in step 2 above, except that an equal mass of ZnIn2S4 was used instead of g-C3N4 / ZnIn2S4).

[0039] Example 9

[0040] Photocatalytic water splitting to produce hydrogen: 0.1 g g-C3N4 catalyst was added to 100 mL of 10% TEOA solution. A 300 W xenon lamp (420 nm-800 nm) was used to simulate the sunlight. The xenon lamp operating current was 15 mA and the illumination time was 1 h.

[0041] In this reaction, the photocatalytic water splitting hydrogen production rate is 0 μmol / g / h.

[0042] Example 10

[0043] (1) Preparation of Co III (dmgH)2(4-(Me2N)py)Cl / g-C3N4 / ZnIn2S4 composite catalyst: Weigh 0.0001g Co III (dmgH)2(4-(Me2N)py)Cl and 0.1g g-C3N4 / ZnIn2S4 (prepared in Example 4) were placed in 30mL of ethanol solution and sonicated for 30min. Then, a solution containing Co was added. III A solution of (dmgH)2(4-(Me2N)py)Cl was added to a solution containing g-C3N4 / ZnIn2S4 and stirred vigorously for 6 hours. The resulting mixed suspension was then stirred vigorously until dry, and ground to obtain Co. IIICo with a mass ratio of (dmgH)2(4-(Me2N)py)Cl to g-C3N4 / ZnIn2S4 of 0.1 (wt%) III (dmgH)2(4-(Me2N)py)Cl / g-C3N4 / ZnIn2S4 composite catalyst. (2) Photocatalytic water splitting to produce hydrogen: 0.1g of composite photocatalyst was added to 100mL of 10% TEOA solution. A 300W xenon lamp (420nm-800nm) was used to simulate the sun's light source. The xenon lamp's working current was 15mA and the illumination time was 1h. (3) In this reaction, the photocatalytic water splitting hydrogen production rate was 854 μmol / g / h, which was 2.1 times higher than that of ZnIn2S4 alone (0.1 g ZnIn2S4 was used as a control instead of the photocatalyst, and the process and conditions were the same as in step 2 above, except that an equal mass of ZnIn2S4 was used instead of Co). III (dmgH)2(4-(Me2N)py)Cl / g-C3N4 / ZnIn2S4).

[0044] Example 11

[0045] The process and conditions are the same as in Example 10, except that Co in step (1) is different. III The amount of (dmgH)2(4-(Me2N)py)Cl used was 0.0005g, and Co was obtained. III (dmgH)2(4-(Me2N)py)Cl accounted for Co III g-C3N4 / ZnIn2S4 composite photocatalyst with a mass ratio of (dmgH)2(4-(Me2N)py)Cl / g-C3N4 / ZnIn2S4 of 0.5 (Wt%).

[0046] In this reaction, the photocatalytic water splitting hydrogen production rate was 930 μmol / g / h, which was 2.3 times higher than that of ZnIn2S4 alone (0.1 g ZnIn2S4 was used as a control instead of the photocatalyst, and the process and conditions were the same as in step 2 above, except that an equal mass of ZnIn2S4 was used instead of Co). III (dmgH)2(4-(Me2N)py)Cl / g-C3N4 / ZnIn2S4).

[0047] Example 12

[0048] The process and conditions are the same as in Example 10, except that Co in step (1) is different. III The amount of (dmgH)2(4-(Me2N)py)Cl used was 0.001g, and Co was obtained. III(dmgH)2(4-(Me2N)py)Cl accounted for Co III (dmgH)2(4-(Me2N)py)Cl / g-C3N4 / ZnIn2S4 mass ratio 1.0 (Wt%) of Co III (dmgH)2(4-(Me2N)py)Cl / g-C3N4 / ZnIn2S4 composite photocatalyst.

[0049] In this reaction, the photocatalytic water splitting hydrogen production rate was 1000 μmol / g / h, which was 2.4 times higher than that of ZnIn2S4 alone (0.1 g ZnIn2S4 was used as a control instead of the photocatalyst, and the process and conditions were the same as in step 2 above, except that an equal mass of ZnIn2S4 was used instead of Co). III (dmgH)2(4-(Me2N)py)Cl / g-C3N4 / ZnIn2S4).

[0050] Example 13

[0051] The process and conditions are the same as in Example 10, except that Co in step (1) is different. III The amount of (dmgH)2(4-(Me2N)py)Cl used was 0.002 g, and Co was obtained. III (dmgH)2(4-(Me2N)py)Cl accounted for Co III (dmgH)2(4-(Me2N)py)Cl / g-C3N4 / ZnIn2S4 mass ratio 2.0 (Wt%) of Co III (dmgH)2(4-(Me2N)py)Cl / g-C3N4 / ZnIn2S4 composite photocatalyst.

[0052] In this reaction, the photocatalytic water splitting hydrogen production rate was 1180 μmol / g / h, which was 2.8 times higher than that of ZnIn2S4 alone (0.1 g ZnIn2S4 was used as a control instead of the photocatalyst, and the process and conditions were the same as in step 2 above, except that an equal mass of ZnIn2S4 was used instead of Co). III (dmgH)2(4-(Me2N)py)Cl / g-C3N4 / ZnIn2S4).

[0053] Example 14

[0054] The process and conditions are the same as in Example 10, except that Co in step (1) is different. III The amount of (dmgH)2(4-(Me2N)py)Cl used was 0.0025g, and Co was obtained. III (dmgH)2(4-(Me2N)py)Cl accounted for Co III(dmgH)2(4-(Me2N)py)Cl / g-C3N4 / ZnIn2S4 mass ratio 2.5 (Wt%) of Co III (dmgH)2(4-(Me2N)py)Cl / g-C3N4 / ZnIn2S4 composite photocatalyst.

[0055] In this reaction, the photocatalytic water splitting hydrogen production rate was 1350 μmol / g / h, which was 3.3 times higher than that of ZnIn2S4 alone (0.1 g ZnIn2S4 was used as a control instead of the photocatalyst, and the process and conditions were the same as in step 2 above, except that an equal mass of ZnIn2S4 was used instead of Co). III (dmgH)2(4-(Me2N)py)Cl / g-C3N4 / ZnIn2S4).

[0056] Example 15

[0057] The process and conditions are the same as in Example 10, except that Co in step (1) is different. III The amount of (dmgH)2(4-(Me2N)py)Cl used was 0.003g, and Co was obtained. III (dmgH)2(4-(Me2N)py)Cl accounted for Co III Co with a mass ratio of (dmgH)2(4-(Me2N)py)Cl / g-C3N4 / ZnIn2S4 of 3.0 (wt%) III (dmgH)2(4-(Me2N)py)Cl / g-C3N4 / ZnIn2S4 composite photocatalyst.

[0058] In this reaction, the photocatalytic water splitting hydrogen production rate was 1235 μmol / g / h, which was 3 times higher than that of ZnIn2S4 alone (0.1 g ZnIn2S4 was used as a control instead of the photocatalyst, and the process and conditions were the same as in step 2 above, except that an equal mass of ZnIn2S4 was used instead of Co). III (dmgH)2(4-(Me2N)py)Cl / g-C3N4 / ZnIn2S4).

[0059] Example 16

[0060] The process and conditions are the same as in Example 10, except that Co in step (1) is different. III The amount of (dmgH)2(4-(Me2N)py)Cl used was 0.004 g, and Co was obtained. III (dmgH)2(4-(Me2N)py)Cl accounted for Co III(dmgH)2(4-(Me2N)py)Cl / g-C3N4 / ZnIn2S4 mass ratio 4.0 (Wt%) of Co III (dmgH)2(4-(Me2N)py)Cl / g-C3N4 / ZnIn2S4 composite photocatalyst.

[0061] In this reaction, the photocatalytic water splitting hydrogen production rate was 1110 μmol / g / h, which was 2.7 times higher than that of ZnIn2S4 alone (0.1 g ZnIn2S4 was used as a control instead of the photocatalyst, and the process and conditions were the same as in step 2 above, except that an equal mass of ZnIn2S4 was used instead of Co). III (dmgH)2(4-(Me2N)py)Cl / g-C3N4 / ZnIn2S4).

[0062] Example 17

[0063] Photocatalytic water splitting to produce hydrogen: 0.1g Co III The (dmgH)2(4-(Me2N)py)Cl catalyst was added to 100 mL of 10% TEOA solution. A 300W xenon lamp (420nm-800nm) was used to simulate the sunlight. The xenon lamp operating current was 15mA and the illumination time was 1h.

[0064] In this reaction, the photocatalytic water splitting hydrogen production rate is 0 μmol / g / h.

Claims

1. The application of a composite catalyst in the photocatalytic water splitting process for hydrogen production, characterized in that: The composite catalyst is used for photocatalytic water splitting to produce hydrogen; the wavelength range is 420 nm-800 nm, and the composite catalyst is Co. III (dmgH)2(4-(Me2N)py)Cl / g-C3N4 / ZnIn2S4, this catalyst is composed of Co III It is composed of (dmgH)2(4-(Me2N)py)Cl, g-C3N4 and ZnIn2S4; Co III The mass ratio of (dmgH)2(4-(Me2N)py)Cl and g-C3N4 / ZnIn2S4 is 2.0%~3.0%; The mass ratio of g-C3N4 to ZnIn2S4 is 1.5%~2.5%.

2. The application according to claim 1, characterized in that: Co III (dmgH)2(4-(Me2N)py)Cl is loaded onto g-C3N4 / ZnIn2S4; g-C3N4 / ZnIn2S4 is a complex formed by adding g-C3N4 during the synthesis of ZnIn2S4.

3. The application according to claim 1, characterized in that: Co III The mass ratio of (dmgH)2(4-(Me2N)py)Cl and g-C3N4 / ZnIn2S4 is 2.4%~2.6%; The mass ratio of g-C3N4 to ZnIn2S4 is 1.9%~2.1%.

4. An application according to claim 1 or 2, characterized in that: (1) Co was prepared by organic synthesis using cobalt chloride, dimethylglyoxime and 4-dimethylaminopyridine as raw materials, followed by heating and oxidation. III (dmgH)2(4-(Me2N)py)Cl; (2) g-C3N4 was prepared from melamine; (3) g-C3N4 / ZnIn2S4 was prepared from g-C3N4, zinc chloride, indium chloride tetrahydrate, and thioacetamide by hydrothermal method, with a mass ratio of g-C3N4 to ZnIn2S4 of 1.5%~2.5%; (4) Co was obtained by impregnation method. III (dmgH)2(4-(Me2N)py)Cl / g-C3N4 / ZnIn2S4,Co III The mass ratio of (dmgH)2(4-(Me2N)py)Cl and g-C3N4 / ZnIn2S4 is 2.0%~3.0%.

5. The application according to claim 4, characterized in that, Step (1) Co III The specific preparation process of (dmgH)2(4-(Me2N)py)Cl is as follows: The container is evacuated and N2 / O2 (volume ratio 95-99:1-5) is repeatedly introduced 2-4 times. 100 mL of 93%-98% ethanol solution is added; 2.4 g-2.8 g of cobalt chloride hexahydrate and 2.6 g-2.9 g of dimethylglyoxime are added. The solution is heated to 68℃-75℃, followed by the addition of 1.3 g-1.4 g of 4-dimethylaminopyridine. The resulting solution is then cooled to room temperature. Air is then introduced into the solution for 30-60 minutes to produce a precipitate. The obtained solid product is filtered, washed, and dried to obtain Co. III (dmgH)2(4-(Me2N)py)Cl.

6. The application according to claim 5, characterized in that, Step (1) Co III The specific preparation process of (dmgH)2(4-(Me2N)py)Cl is as follows: The container is evacuated and N2 / O2 (volume ratio 98-99:1-2) is repeatedly introduced 2-4 times. 100 mL of 95%-96% ethanol solution is added; 2.5 g-2.7 g of cobalt chloride hexahydrate and 2.7 g-2.8 g of dimethylglyoxime are added. The solution is heated to 69℃-72℃, followed by the addition of 1.31 g-1.32 g of 4-dimethylaminopyridine. The resulting solution is then cooled to room temperature. Air is then introduced into the solution for 40-50 minutes to produce a precipitate. The obtained solid product is filtered, washed, and dried to obtain Co. III (dmgH)2(4-(Me2N)py)Cl.

7. The application according to claim 4, characterized in that, The specific preparation process of g-C3N4 in step (2) is as follows: using 5g~10g of melamine as a precursor, heating at a heating rate of 2℃ / min~3℃ / min to 540℃~570℃ for 2h~5h, and then grinding to obtain g-C3N4 powder.

8. The application according to claim 7, characterized in that, The specific preparation process of g-C3N4 in step (2) is as follows: using 6g~9g of melamine as a precursor, heating at a heating rate of 2.3℃ / min~2.5℃ / min to 550℃~560℃ for 3h~4h, and then grinding to obtain g-C3N4 powder.

9. The application according to claim 4, characterized in that, The specific preparation process of g-C3N4 / ZnIn2S4 in step (3) is as follows: control the mass ratio of g-C3N4 and ZnIn2S4 to 2.0%~3.0%, take 0.01 g~0.03 g g-C3N4 and dissolve it in 50 mL~70 mL of deionized water, add 0.13 g~0.16 g ZnCl2, 0.65 g~0.70 g InCl3·4H2O and 0.60 g~0.70 g thioacetamide to the solution and stir evenly. Transfer the solution to a hydrothermal reactor and react at 170℃~190℃ for 10 h~15 h. After precipitating, washing, drying and grinding, g-C3N4 / ZnIn2S4 powder is obtained.

10. The application according to claim 9, characterized in that, The specific preparation process of g-C3N4 / ZnIn2S4 in step (3) is as follows: control the mass ratio of g-C3N4 to ZnIn2S4 to be 2.3%~2.6%, take 0.01 g~0.02 g g-C3N4 and dissolve it in 55 mL~65 mL of deionized water, add 0.14 g~0.16 g ZnCl2, 0.67 g~0.69 g InCl3·4H2O and 0.61 g~0.65 g thioacetamide to the solution and stir evenly. Transfer the solution to a hydrothermal reactor and react at 178℃~182℃ for 11 h~13 h. After precipitating, washing, drying and grinding, g-C3N4 / ZnIn2S4 powder is obtained.

11. The application according to claim 4, characterized in that, Step (4) Co III The specific preparation process of (dmgH)2(4-(Me2N)py)Cl / g-C3N4 / ZnIn2S4 is as follows: Based on Co III The mass ratio of (dmgH)2(4-(Me2N)py)Cl and g-C3N4 / ZnIn2S4 is 2.0%~3.0%, and Co is added. III (dmgH)2(4-(Me2N)py)Cl and g-C3N4 / ZnIn2S4 were dissolved in ethanol and sonicated for 2-6 hours, then containing Co III A solution of (dmgH)2(4-(Me2N)py)Cl was added to a solution containing g-C3N4 / ZnIn2S4. The solution was stirred, evaporated to dryness, and then ground to obtain Co. III (dmgH)2(4-(Me2N)py)Cl / g-C3N4 / ZnIn2S4 composite catalyst.

12. The application according to claim 11, characterized in that, Co III The mass ratio of (dmgH)2(4-(Me2N)py)Cl and g-C3N4 / ZnIn2S4 was 2.3%~2.6%, and the mixture was sonicated for 3 h~5 h.

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