S-doped ReSe2 photocatalytic hydrogen promoter as well as preparation method and application thereof
By doping the ReSe2 photocatalyst with sulfur atoms, the problems of high photogenerated carrier recombination rate and slow interfacial reaction rate of the TiO2 photocatalyst are solved, and the efficient photocatalytic hydrogen evolution effect is achieved, and the preparation method is simple and safe.
Patent Information
- Application Number
- CN202510483001.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-04-17
- Publication Date
- 2025-07-04
AI Technical Summary
The high photogenerated carrier recombination rate of the existing TiO2 photocatalysts and the slow interfacial catalytic reaction rate leads to low catalytic efficiency and unstable Se-Had bonds, which suppresses the H2 generation rate.
Doping the ReSe2 photocatalyst by sulfur atoms, electron-deficient Se(2-δ)-active sites are formed, reducing the anti-bond orbital occupancy state of the Se-Had bond, enhancing the adsorption ability of Se to atomic Had, and using a one-step photodeposition method to load the ReSxSe2-x hydrogen evolution cocatalyst on the surface of TiO2.
The photocatalytic hydrogen production performance is improved, the separation effect of hydrogen evolution active sites and photogenerated carriers is enhanced, and the efficient visible photocatalytic decomposition of water is achieved to produce hydrogen.
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Figure CN120243064A_ABST
Abstract
Description
Technical Field
[0001] The embodiments of the present invention relate to the technical field of catalyst materials, and in particular to an S-doped ReSe2 photocatalytic hydrogen evolution cocatalyst and its preparation method and application. Background Art
[0002] H2 is a clean and pollution-free renewable energy source, and is expected to be widely used in the future to meet the daily production and life of humans. Hydrogen energy itself has the advantages of high calorific value (140 MJ kg -1 ), rich sources, and no secondary pollution of combustion products. Its production technology has been widely studied worldwide. At present, the main methods for producing H2 are: electrolysis of water, thermal decomposition, and photocatalytic decomposition of water. Photocatalytic decomposition of water to produce hydrogen is considered to be one of the most promising ways to obtain hydrogen energy.
[0003] In recent years, using solar energy, which is clean, pollution-free, and rich in sources, for semiconductor photocatalytic hydrogen production is an environmentally friendly and sustainable approach. This technology can be carried out under mild conditions (room temperature and normal pressure) and does not require other additional energy sources except solar energy, so it has attracted the attention of many researchers.
[0004] In addition, TiO2 is a most common ultraviolet light-responsive photocatalytic material, and at the same time has the advantages of being cheap, low-toxic, stable in nature, and easy to prepare, making it widely studied in the field of photocatalysis. However, limited by the nature of TiO2 itself, such as a high recombination probability of photo-generated carriers and a slow interfacial catalytic reaction rate, the photocatalytic production of H2 by pure TiO2 is greatly restricted, and the catalytic efficiency is low.
[0005] Metal chalcogenides have good applications in photocatalytic hydrogen evolution due to their unique electronic configurations and effective catalytic activities. Theoretical and experimental analyses show that their catalytic performance is mainly due to unsaturated chalcogen elements (such as S, Se, and Te) acting as hydrogen evolution active centers by forming chalcogen-hydrogen bonds (chalcogen-H ad ). Therefore, the present invention selects to load the ReSe2 cocatalyst. However, the Se-H ad bond is usually unstable, making the adsorption of H ad intermediates quite difficult, which greatly inhibits their H2 production rate. Therefore, the present invention rationally regulates the microelectronic structure of the Se element active site by doping S atoms, and optimizes the Se-H ad bond to achieve rapid adsorption and desorption of atomic H, and achieve high-efficiency photocatalytic hydrogen evolution efficiency. Summary of the Invention
[0006] The object of the present invention is to provide an S-doped ReSe2 photocatalytic hydrogen evolution cocatalyst, its preparation method and application. Through sulfur atom doping modification, the electron density of Se atoms can be reduced to form electron-deficient Se (2-δ)- active sites, reducing the anti-bonding orbital occupancy state of the Se-H ad bond during the hydrogen production process, thereby enhancing the adsorption ability of Se to atomic H ad and accelerating the kinetic reaction rate of interfacial hydrogen evolution, making the ReS x Se 2-x hydrogen evolution cocatalyst have higher photocatalytic hydrogen production performance.
[0007] To achieve the above object, the present invention provides a preparation method of an S-doped ReSe2 photocatalytic hydrogen evolution cocatalyst, including:
[0008] Adding anatase titanium dioxide into a mixed solution of ethanol and water, performing ultrasonic dispersion, then adding an aqueous solution of sodium perrhenate, a sulfur source and a selenium source. The obtained suspension is evacuated of air in the system with pure N2 and then sealed. The ReS x Se 2-x hydrogen evolution cocatalyst is deposited on TiO2 by a photodeposition method. The obtained product is centrifuged, washed and dried to obtain the catalyst TiO2 / ReS x Se 2-x , 0 < x < 2.
[0009] Further, 0.8 < x < 1.5.
[0010] Further, the selenium source is an ethanol solution of dibenzyl diselenide, and the sulfur source is an ethanol solution of dibenzyl disulfide.
[0011] Further, the concentration of the ethanol solution of dibenzyl diselenide is 0.001 - 0.02 mol / L, the concentration of the ethanol solution of dibenzyl disulfide is 0.001 - 0.02 mol / L, and the concentration of the aqueous solution of sodium perrhenate is 0.01 - 0.1 mol / L.
[0012] Further, the mass fraction of rhenium in the aqueous solution of sodium perrhenate added to TiO2 is 0 - 5 wt%, and the total amount of sulfur and selenium atoms in the added sulfur source and selenium source is 0.001 - 10 times that of rhenium atoms.
[0013] Further, the photodeposition is to irradiate the suspension under a xenon lamp for 0.5 - 2 hours; the power of the xenon lamp is 300 W.
[0014] Specifically, a preparation method of an S-doped ReSe2 photocatalyst hydrogen evolution cocatalyst includes:
[0015] Take anatase titanium dioxide in a three-necked flask, add an ethanol-aqueous solution (anhydrous ethanol accounts for 30% of the total volume of the solution), perform ultrasonic treatment, add an aqueous solution of sodium perrhenate to the three-necked flask, and add a dibenzyl diselenide-ethanol solution and a dibenzyl disulfide-ethanol solution in different ratios. The resulting suspension is evacuated of air in the system with pure N2, the tube mouth is sealed, and then placed under a xenon lamp for illumination. The product is centrifuged, washed, and dried to obtain the catalyst TiO2 / ReS x Se 2-x .
[0016] Furthermore, the preparation method of the anatase titanium dioxide includes:
[0017] Add tetrabutyl titanate to deionized water, and age at room temperature for 12 - 30 h to obtain amorphous TiO2. After centrifugation, washing, and drying, calcine at 450 - 650 °C and grind to obtain anatase titanium dioxide.
[0018] Furthermore, the volume ratio of tetrabutyl titanate to deionized water is 1:12 (10 - 15);
[0019] When washing, wash 3 times with deionized water and anhydrous ethanol respectively;
[0020] The calcination time is 2 - 5 h.
[0021] Specifically, the preparation method of anatase titanium dioxide includes:
[0022] Take 600 mL of deionized water in a 1000 mL beaker, and dropwise add 50 mL of tetrabutyl titanate under magnetic stirring; after the addition is complete, continue to stir the suspension for 2 hours, and then age overnight at room temperature for 18 hours; the obtained amorphous TiO2 is centrifuged and washed 3 times with deionized water and ethanol respectively. The white solid is dried in an oven at 60 °C for 24 hours and then transferred to a crucible, calcined in a muffle furnace at a heating rate of 5 °C / min at 550 °C for 4 hours. The product is fully ground and then placed in a sealed bottle for standby. The obtained white solid is the anatase TiO2 material.
[0023] An S-doped ReSe2 photocatalytic hydrogen evolution cocatalyst obtained by the preparation method described in any one of the above.
[0024] An application of the S-doped ReSe2 photocatalytic hydrogen evolution cocatalyst described above, including: dispersing the TiO2 / ReS x Se 2-x catalyst uniformly in a mixed solvent of ethanol and water with a volume fraction of 0 - 50%, and performing photocatalytic hydrogen production of H2 using a xenon lamp under normal temperature environment and nitrogen atmosphere.
[0025] The present invention has the following beneficial effects:
[0026] 1. The preparation method of the novel S-doped ReSe2 hydrogen evolution cocatalyst provided by the present invention deposits ReS x Se 2-x hydrogen evolution cocatalyst on the surface of TiO2 material through a one-step photodeposition approach, which is simpler and safer than other synthesis methods. Moreover, by controlling the volume of the selenium source / sulfur source precursor solution added, the ratio of sulfur atoms to selenium atoms in the S-doped ReSe2 hydrogen evolution cocatalyst can be controlled, realizing the controllable synthesis of ReS x Se 2-x hydrogen evolution cocatalyst. The photocatalyst provided by the present invention has more hydrogen evolution active sites and a lower photogenerated carrier recombination rate, thus showing higher visible light catalytic water splitting hydrogen production activity.
[0027] 2. The novel S-doped ReSe2 photocatalytic hydrogen evolution cocatalyst provided by the present invention is a highly efficient photocatalytic hydrogen evolution cocatalyst modified by sulfur atom doping. Introducing S into the structure of ReSe2 can reduce the electron density of Se atoms to form electron-deficient Se (2-δ)- active sites, reduce the occupancy of the antibonding orbital of the Se-H ad bond during the hydrogen production process, thereby enhancing the adsorption ability of Se to atomic H ad and accelerating the kinetic reaction rate of interfacial hydrogen evolution, making the ReS x Se 2-x hydrogen evolution cocatalyst have higher photocatalytic hydrogen production performance. Description of the Drawings
[0028] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the following drawings are only some embodiments of the present invention. For those skilled in the art, without creative efforts, other drawings can also be obtained based on these drawings.
[0029] Figure 1 SEM image of the S-doped ReSe2 photocatalytic hydrogen evolution cocatalyst in Example 1 of the present invention;
[0030] Figure 2 TEM image of the S-doped ReSe2 photocatalytic hydrogen evolution cocatalyst in Example 1 of the present invention;
[0031] Figure 3 HRTEM image of the S-doped ReSe2 photocatalytic hydrogen evolution cocatalyst in Example 1 of the present invention;
[0032] Figure 4 UV-Vis diffuse reflectance spectra of the S-doped ReSe2 photocatalytic hydrogen evolution cocatalyst in Comparative Example 1 and Examples 1-3 of the present invention;
[0033] Figure 5 This is the transient photoluminescence spectrum of the S-doped ReSe2 photocatalytic hydrogen evolution cocatalyst in Comparative Example 1 and Examples 1-3 of the present invention;
[0034] Figure 6 This is the photovoltage test chart of the S-doped ReSe2 photocatalytic hydrogen evolution cocatalyst in Comparative Example 1 and Examples 1-3 of the present invention;
[0035] Figure 7 This is the visible light photocatalytic hydrogen production rate chart of the S-doped ReSe2 photocatalytic hydrogen evolution cocatalyst in Comparative Example 1 and Examples 1-3 of the present invention;
[0036] Figure 8 This is the photocatalytic cycle stability chart of the S-doped ReSe2 photocatalytic hydrogen evolution cocatalyst in Example 1 of the present invention. Detailed implementation manners
[0037] In order to enable those skilled in the art to better understand the solution of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention.
[0038] Comparative Example 1
[0039] Prepare anatase titanium dioxide:
[0040] Take 600 mL of deionized water in a 1000 mL beaker, and dropwise add 50 mL of tetrabutyl titanate under magnetic stirring; after the addition is complete, the suspension is continuously stirred for 2 hours, and then aged overnight at room temperature for 18 hours; the obtained amorphous TiO2 is centrifuged and washed 3 times with deionized water and ethanol respectively. The white solid is dried in an oven at 60 °C for 24 hours and then transferred to a crucible, calcined in a muffle furnace at a heating rate of 5 °C / min at 550 °C for 4 hours. After the product is sufficiently ground, it is put into a sealed bottle for standby. The obtained white solid is the anatase TiO2 material, which is compared with the composite photocatalyst obtained by loading the S-doped ReSe2 photocatalytic hydrogen evolution cocatalyst on TiO2 by photodeposition.
[0041] Example 1
[0042] Prepare the S-doped ReSe2 photocatalytic hydrogen evolution cocatalyst by a one-step photodeposition method:
[0043] 1. Take 50 mg of anatase titanium dioxide in a 100 mL three-necked flask, add 80 mL of ethanol-aqueous solution (anhydrous ethanol accounts for 30% of the total volume of the solution), and ultrasonicate for 5 minutes;
[0044] 2. Add 81 μL of sodium perrhenate-aqueous solution (0.1 mol L-1 )、1620 μL of dibenzyl diselenide - ethanol solution (0.01 mol / L -1 ) and 2430 μL of dibenzyl disulfide - ethanol solution (0.01 mol / L -1 );
[0045] 3. The obtained suspension was purged with pure N2 to remove the air in the system (ventilated for 15 min), the tube mouth was sealed, and then placed under a xenon lamp (with a power of 300 W) for light irradiation for 2 hours. After the product was centrifuged, washed, and dried, the catalyst TiO2 / ReS 1.2 Se 0.8 .
[0046] Example 2 - 3
[0047] The preparation method of the hydrogen evolution cocatalyst in Example 2 - 3 is the same as that shown in Example 1. The difference is only that in step 2, the contents of dibenzyl disulfide and dibenzyl diselenide provided with S and Se are different. The ratios of S and Se in each example are shown in Table 1.
[0048] Table 1. Ratios of S and Se in Example 2 - 3
[0049]
[0050] Sample characterization:
[0051] The TiO2 / ReS 1.2 Se 0.8 , TiO2 / ReS2, TiO2 / ReSe2 prepared in Examples 1 - 3 and TiO2 of Comparative Example 1 were characterized by materials, such as Figure 1 shown SEM, such as Figure 2 and Figure 3 shown TEM and HRTEM images, such as Figure 4 shown UV - vis image and such as Figure 5 and Figure 6 shown transient photoluminescence spectrum and photovoltage image.
[0052] Taking the TiO2 / ReS 1.2 Se 0.8 prepared in Example 1 as an example for illustration. It can be observed from Figure 2 and Figure 3 that the prepared TiO2 / ReS 1.2 Se 0.8 composite photocatalytic material is composed of nanoparticles with a size of about 50 - 200 nm, which is similar to the morphological structure of pure TiO2, indicating that the morphology of TiO2 will not be changed during the one - step photodeposition process of preparing the S - doped ReSe2 cocatalyst. At the same time, in Figure 3The lattice fringes of TiO2 can be observed in the high-resolution transmission electron microscope, and the measured lattice spacing is about 0.35 nm. This result further indicates that the preparation of S-doped ReSe2 photocatalytic hydrogen evolution cocatalyst by photodeposition does not change the morphology of TiO2. Figure 4 shows TiO2 / ReS 1.2 Se 0.8 The UV-Vis diffuse reflectance spectra of can be seen that, compared with TiO2, the absorption edge of this composite photocatalytic material does not move significantly, indicating that the cocatalyst is not doped into the lattice of TiO2, but is only deposited on the surface of TiO2.
[0053] In Figure 5 the TiO2 / ReS 1.2 Se 0.8 sample has the lowest fluorescence intensity, indicating that the loading of S-doped ReSe2 cocatalyst can promote the separation of photogenerated carriers in TiO2. Figure 6 Photovoltage tests show that the S-doped ReSe2 cocatalyst modified TiO2 composite photocatalytic material can show a higher photovoltage response under light irradiation, and the separation effect of electrons and holes on the surface composite photocatalytic material is the best, enabling more photogenerated electrons to be separated and participate in the subsequent interfacial hydrogen evolution reaction.
[0054] Photocatalytic hydrogen production performance test:
[0055] The photocatalytic hydrogen production performance of the photocatalyst prepared in this example was tested using a PLS-SXE300 xenon lamp light source from Beijing Perfectlight Technology Co., Ltd. (lamp power: 300 W; maximum current: 21 A) and an SP-6801A gas chromatograph from Shandong Lunan Ruihong Chemical Co., Ltd.
[0056] The specific steps are as follows:
[0057] 1. Disperse 50 mg of TiO2 / ReS 1.2 Se 0.8 catalyst in a three-necked flask containing 80 mL of ethanol-aqueous solution with 30 vol% (anhydrous ethanol accounts for 30% of the total volume of the solution), and pass nitrogen for 15 min to remove the impurity gas in the bottle.
[0058] 2. Under ambient temperature and atmospheric pressure, use a xenon lamp as the excitation light source to perform the photocatalytic H2 generation activity test under stirring.
[0059] 3. Use a gas chromatograph to measure the hydrogen content in the bottle.
[0060] Specifically: 0.4 mL of gas is extracted from the bottle every 30 minutes and quickly injected into the gas chromatograph. The data is integrated to calculate the peak area, and finally the hydrogen production is obtained through a calculation formula. After continuous illumination for 2 hours, the hydrogen production rate is calculated by plotting the relationship curve between the hydrogen amount and time.
[0061] Figure 7 shows the influence of ReSe2 cocatalysts with different S doping contents loaded on the hydrogen production performance of TiO2 photocatalysts. From Figure 7 it can be seen that after loading the S-doped ReSe2 cocatalyst, the hydrogen production activity of the composite photocatalyst is significantly enhanced compared with the original TiO2. Among them, the TiO2 / ReS 1.2 Se 0.8 composite photocatalyst can reach a hydrogen production rate of 2035 μmol·g -1 after 2 hours of illumination, showing the highest visible-light photocatalytic hydrogen production activity.
[0062] Photocatalytic stability test:
[0063] Select the TiO2 / ReS 1.2 Se 0.8 sample with the best performance as the research object for the photocatalytic cyclic hydrogen production experiment. The basic steps are basically the same as those for the photocatalytic hydrogen production performance test. After completing the first 2-hour hydrogen production test, nitrogen is introduced for 15 minutes to remove the hydrogen in the three-necked flask. Then continue illumination for hydrogen production, and repeat 4 times in total to obtain the results as Figure 8 shown. As shown in the figure, the TiO2 / ReS 1.2 Se 0.8 sample still maintains a relatively stable photocatalytic hydrogen production rate in the four photocatalytic hydrogen production experiments. Compared with the hydrogen production result of the first time, the hydrogen production concentration only slightly decreases during the fourth run. The results show that the prepared TiO2 / ReS 1.2 Se 0.8 photocatalyst has good photocatalytic hydrogen production cyclic stability.
[0064] Obviously, the above embodiments are only examples clearly described and not limitations on the implementation manners. For those of ordinary skill in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to enumerate all the implementation manners here. And the obvious changes or modifications derived therefrom still fall within the protection scope of the present invention.
[0065] The above are only some implementation manners of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the principle of the present invention, several improvements and refinements can be made, and these improvements and refinements should also be regarded as within the protection scope of the present invention.
Claims
1. A preparation method of an S-doped ReSe2 photocatalytic hydrogen evolution cocatalyst, characterized in that, Comprising: Add anatase titanium dioxide to a mixed solution of ethanol and water, perform ultrasonic dispersion, then add an aqueous solution of sodium perrhenate, a sulfur source, and a selenium source. The resulting suspension is evacuated of air in the system with pure N2 and then sealed. The hydrogen evolution cocatalyst ReS x Se 2-x is deposited on TiO2 by a photodeposition method. The resulting product is centrifuged, washed, and dried to obtain the catalyst TiO2 / ReS x Se 2-x , where 0 < x < 2.
2. The preparation method according to claim 1, characterized in that, 0.8<x<1.5。 3. The preparation method according to claim 1, characterized in that, The selenium source is a dibenzyl diselenide ethanol solution, and the sulfur source is a dibenzyl disulfide ethanol solution.
4. The preparation method according to claim 3, characterized in that, The concentration of the dibenzyl diselenide ethanol solution is 0.001 - 0.02 mol / L, the concentration of the dibenzyl disulfide ethanol solution is 0.001 - 0.02 mol / L, and the concentration of the sodium perrhenate aqueous solution is 0.01 - 0.1 mol / L.
5. The preparation method according to claim 3, characterized in that, The mass fraction of rhenium added to the sodium perrhenate aqueous solution in TiO2 is 0 - 5 wt%, and the total amount of substance of sulfur and selenium atoms in the added sulfur source and selenium source is 0.001 - 10 times that of rhenium atoms.
6. The preparation method according to claim 1, characterized in that, The photodeposition is to place the suspension under a xenon lamp for illumination for 0.5 - 2 hours; the power of the xenon lamp is 300 W.
7. The preparation method according to any one of claims 1-6, characterized in that, The preparation method of the anatase phase titanium dioxide includes: Adding tetrabutyl titanate to deionized water, aging at room temperature for 12 - 30 h to obtain amorphous TiO2, and after centrifugation, washing, and drying, calcining at 450 - 650 °C and grinding to obtain anatase phase titanium dioxide.
8. The preparation method according to claim 7, wherein, The volume ratio of tetrabutyl titanate to deionized water is 1:(10 - 15); During the washing, deionized water and absolute ethanol are used to wash 3 times respectively; The calcination time is 2 - 5 h.
9. An S-doped ReSe2 photocatalytic hydrogen evolution cocatalyst obtained by the preparation method according to any one of claims 1 - 8.
10. Use of the S-doped ReSe2 photocatalytic hydrogen evolution cocatalyst according to claim 9, characterized in that, Comprising: Disperse the TiO2 / ReS x Se 2-x catalyst uniformly in a mixed solvent of ethanol and water with a volume fraction of 0 to 50%, and perform photocatalytic H2 generation using a xenon lamp under normal temperature environment and nitrogen atmosphere.